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  1. Longitudinal and transverse spin asymmetries for inclusive jet production at mid-rapidity in polarized p+p collisions at sqrt{s}=200 GeV
    Autor*in: Adamczyk, L.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Alekseev, I.; Alford, J.; Anderson, B. D.; Anson, C. D.; Arkhipkin, D.; Aschenauer, E.; Averichev, G. S.; Balewski, J.; Banerjee, A.; Barnovska, Z.; Beavis, D. R.; Bellwied, R.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Bridgeman, A.; Brovko, S. G.; Bruna, E.; Bueltmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Cai, X. Z.; Caines, H.; Sánchez, M. Calderón De La Barca; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Chen, Lin; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chung, P.; Chwastowski, J.; Codrington, M. J. M.; Corliss, R.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Leyva, A. Davila; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; De Souza, R. Derradi; Dhamija, S.; Didenko, L.; Ding, F.; Dion, A.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Elnimr, M.; Engelage, J.; Eppley, G.; Eun, L.; Evdokimov, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Fersch, R. G.; Filip, P.; Finch, E.; Fisyak, Y.; Gagliardi, C. A.; Gangadharan, D. R.; Geurts, F.; Gliske, S.; Gorbunov, Y. N.; Grebenyuk, O. G.; Grosnick, D.; Gupta, S.; Guryn, W.; Haag, B.; Hajkova, O.; Hamed, A.; Han, L-X.; Harris, J. W.; Hays-Wehle, J. P.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huck, P.; Humanic, T. J.; Huo, L.; Igo, G.; Jacobs, W. W.; Jena, C.; Joseph, J.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Kettler, D.; Kikola, D. P.; Kiryluk, J.; Kisiel, A.; Kizka, V.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Koroleva, L.; Korsch, W.; Kotchenda, L.; Kowalik, K.; Kravtsov, P.; Krueger, K.; Kumar, L.; Lamont, M. A. C.; Landgraf, J. M.; Lapointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Leight, W.; LeVine, M. J.; Li, C.; Li, L.; Li, W.; Li, Xiaojian; Li, Y.; Li, Z. M.; Lima, L. M.; Lisa, M. A.; Liu, Franklin; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Lu, Y.; Luo, X.; Luszczak, A.; Ma, G. L.; Ma, Y.G.; Don, D. M. M. D. Madagodagettige; Mahapatra, D. P.; Majka, R.; Mall, O. I.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; Mcdonald, D.; McShane, T. S.; Millane, J.; Mioduszewski, S.; Mitrovski, M. K.; Mohammed, Y.; Mohanty, B.; Mondal, M. M.; Morozov, B.; Munhoz, M. G.; Mustafa, M. K.; Naglis, M.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nogach, L. V.; Novak, J.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Oliveira, R. A. N.; Olson, D.; Ostrowski, P.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Plyku, D.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Powell, C. B.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Redwine, R.; Reed, R.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Ruan, L.; Rusnak, J.; Sahoo, N. R.; Sakrejda, I.; Sakuma, T.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Sarsour, M.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, B.; Schmitz, N.; Schuster, T. R.; Seele, J.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shao, M.; Sharma, B.; Sharma, M.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; DeSouza, U. G.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Staszak, D.; Steadman, S. G.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; De Toledo, A. Szanto; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarini, L. H.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trainor, T. A.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; Van Nieuwenhuizen, G.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wada, M.; Wang, F.; Wang, Gang; Wang, H.; Wang, J. S.; Wang, Qiang; Wang, X. L.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Whitten Jr., C.; Wieman, H.; Wissink, S. W.; Witt, R.; Witzke, W.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, N.; Xu, Q. H.; Xu, Wei-Jiang; Xu, Y.; Xu, Z.; Xue, L.; Yang, Y.; Yepes, P.; Yi, Y.; Yip, K.; Yoo, I-K.; Zawisza, M.; Zbroszczyk, H.; Zhang, J. B.; Zhang, S.; Zhang, W. M.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.; Zoulkarneeva, Y.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    18 pages, 16 figures, 8 tables ; We report STAR measurements of the longitudinal double-spin asymmetry A_LL, the transverse single-spin asymmetry A_N, and the transverse double-spin asymmetries A_Sigma and A_TT for inclusive jet production at... mehr

     

    18 pages, 16 figures, 8 tables ; We report STAR measurements of the longitudinal double-spin asymmetry A_LL, the transverse single-spin asymmetry A_N, and the transverse double-spin asymmetries A_Sigma and A_TT for inclusive jet production at mid-rapidity in polarized p+p collisions at a center-of-mass energy of sqrt{s} = 200 GeV. The data represent integrated luminosities of 7.6 /pb with longitudinal polarization and 1.8 /pb with transverse polarization, with 50-55% beam polarization, and were recorded in 2005 and 2006. No evidence is found for the existence of statistically significant jet A_N, A_Sigma, or A_TT at mid-rapidity. Recent model calculations indicate the A_N results may provide new limits on the gluon Sivers distribution in the proton. The asymmetry A_LL significantly improves the knowledge of gluon polarization in the nucleon.

     
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    Quelle: BASE Fachausschnitt AVL
    Sprache: Englisch
    Medientyp: Aufsatz aus einer Zeitschrift
    Format: Online
    Übergeordneter Titel: ISSN: 1550-7998 ; EISSN: 1550-2368 ; Physical Review D ; http://hal.in2p3.fr/in2p3-00697243 ; Physical Review D, American Physical Society, 2012, 86, pp.032006. ⟨10.1103/PhysRevD.86.032006⟩
    Schlagworte: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  2. Transverse sphericity of primary charged particles in minimum bias proton-proton collisions at sqrt(s)=0.9, 2.76 and 7 TeV
    Autor*in: Abelev, B.; Arbor, N.; Conesa Balbastre, G.; Faivre, J.; Furget, C.; Guernane, R.; Kox, S.; Real, J.S.; Silvestre, C.; Vernet, R.; Belikov, I.; Hippolyte, B.; Jangal, S.; Kuhn, C.; Maire, A.; Roy, C.; Sanchez Castro, X.; Senyukov, S.; Wan, R.; Aphecetche, Laurent; Batigne, Guillaume; Bregant, M.; Delagrange, H.; Driga, O.; Estienne, Magali; Germain, Marie; Lardeux, A.; Lefèvre, F.; Lenhardt, M.; Luquin, L.; Martinez Garcia, Gines; Mas, A.; Massacrier, L.; Matyja, A.; Pillot, Philippe; Schutz, Y.; Shabetai, Alexandre; Stocco, Diego; Ahn, Sang Un; Baek, Y.W.; Baldit, A.; Barret, V.; Bastid, N.; Crochet, P.; Dupieux, P.; Ichou, R.; Lopez, X.; Manso, F.; Marchisone, M.; Porteboeuf-Houssais, S.; Rosnet, P.; Vulpescu, B.; Zhang, X.; Cheshkov, C.; Cheynis, B.; Ducroux, L.; Grossiord, J.-Y.; Guilbaud, Maxime; Tieulent, R.; Uras, A.; Zoccarato, Y.
    Erschienen: 2012
    Verlag:  HAL CCSD ; Springer Verlag (Germany)

    See paper for full list of authors - 21 pages, 11 figures ; Measurements of the sphericity of primary charged particles in minimum bias proton--proton collisions at sqrt(s)=0.9, 2.76 and 7 TeV with the ALICE detector at the LHC are presented. The... mehr

     

    See paper for full list of authors - 21 pages, 11 figures ; Measurements of the sphericity of primary charged particles in minimum bias proton--proton collisions at sqrt(s)=0.9, 2.76 and 7 TeV with the ALICE detector at the LHC are presented. The observable is linearized to be collinear safe and is measured in the plane perpendicular to the beam direction using primary charged tracks with $p_{\rm T}\geq0.5$ GeV/c in $|\eta|\leq0.8$. The mean sphericity as a function of the charged particle multiplicity at mid-rapidity ($N_{\rm ch}$) is reported for events with different $p_{\rm T}$ scales ("soft" and "hard") defined by the transverse momentum of the leading particle. In addition, the mean charged particle transverse momentum versus multiplicity is presented for the different event classes, and the sphericity distributions in bins of multiplicity are presented. The data are compared with calculations of standard Monte Carlo event generators. The transverse sphericity is found to grow with multiplicity at all collision energies, with a steeper rise at low $N_{\rm ch}$, whereas the event generators show the opposite tendency. The combined study of the sphericity and the mean $p_{\rm T}$ with multiplicity indicates that most of the tested event generators produce events with higher multiplicity by generating more back-to-back jets resulting in decreased sphericity (and isotropy). The PYTHIA6 generator with tune PERUGIA-2011 exhibits a noticeable improvement in describing the data, compared to the other tested generators.

     
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    Quelle: BASE Fachausschnitt AVL
    Sprache: Englisch
    Medientyp: Aufsatz aus einer Zeitschrift
    Format: Online
    Übergeordneter Titel: ISSN: 1434-6044 ; EISSN: 1434-6052 ; European Physical Journal C: Particles and Fields ; http://hal.in2p3.fr/in2p3-00699404 ; European Physical Journal C: Particles and Fields, Springer Verlag (Germany), 2012, 72, pp.2124. ⟨10.1140/epjc/s10052-012-2124-9⟩
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]
  3. Di-electron spectrum at mid-rapidity in $p+p$ collisions at $\sqrt{s} = 200$ GeV
    Autor*in: Adamczyk, L.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Alekseev, I.; Alford, J.; Anderson, B. D.; Anson, C. D.; Arkhipkin, D.; Aschenauer, E.; Averichev, G. S.; Balewski, J.; Banerjee, A.; Barnovska, Z.; Beavis, D. R.; Bellwied, R.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bruna, E.; Bueltmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Cai, X. Z.; Caines, H.; Sánchez, M. Calderón De La Barca; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Chen, Lin; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chung, P.; Chwastowski, J.; Codrington, M. J. M.; Corliss, R.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Leyva, A. Davila; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; De Souza, R. Derradi; Dhamija, S.; Didenko, L.; Ding, F.; Dion, A.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Elnimr, M.; Engelage, J.; Eppley, G.; Eun, L.; Evdokimov, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Fersch, R. G.; Filip, P.; Finch, E.; Fisyak, Y.; Gagliardi, C. A.; Gangadharan, D. R.; Geurts, F.; Gibson, A.; Gliske, S.; Gorbunov, Y. N.; Grebenyuk, O. G.; Grosnick, D.; Gupta, S.; Guryn, W.; Haag, B.; Hajkova, O.; Hamed, A.; Han, L-X.; Harris, J. W.; Hays-Wehle, J. P.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huck, P.; Humanic, T. J.; Huo, L.; Igo, G.; Jacobs, W. W.; Jena, C.; Joseph, J.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Kettler, D.; Kikola, D. P.; Kiryluk, J.; Kisel, I.; Kisiel, A.; Kizka, V.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Koroleva, L.; Korsch, W.; Kotchenda, L.; Kravtsov, P.; Krueger, K.; Kumar, L.; Lamont, M. A. C.; Landgraf, J. M.; Lapointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Leight, W.; LeVine, M. J.; Li, C.; Li, L.; Li, W.; Li, Xiaojian; Li, Y.; Li, Z. M.; Lima, L. M.; Lisa, M. A.; Liu, Franklin; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Lu, Y.; Luo, X.; Luszczak, A.; Ma, G. L.; Ma, Y.G.; Don, D. M. M. D. Madagodagettige; Mahapatra, D. P.; Majka, R.; Mall, O. I.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; Mcdonald, D.; McShane, T. S.; Mioduszewski, S.; Mitrovski, M. K.; Mohammed, Y.; Mohanty, B.; Mondal, M. M.; Morozov, B.; Munhoz, M. G.; Mustafa, M. K.; Naglis, M.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nogach, L. V.; Novak, J.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Oliveira, R. A. N.; Olson, D.; Ostrowski, P.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Plyku, D.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Powell, C. B.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Redwine, R.; Reed, R.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Ruan, L.; Rusnak, J.; Sahoo, N. R.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, B.; Schmitz, N.; Schuster, T. R.; Seele, J.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shao, M.; Sharma, B.; Sharma, M.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; DeSouza, U. G.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Steadman, S. G.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; De Toledo, A. Szanto; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarini, L. H.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trainor, T. A.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; Van Nieuwenhuizen, G.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wada, M.; Wang, F.; Wang, Gang; Wang, H.; Wang, J. S.; Wang, Qiang; Wang, X. L.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Whitten Jr., C.; Wieman, H.; Wissink, S. W.; Witt, R.; Witzke, W.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, N.; Xu, Q. H.; Xu, Wei-Jiang; Xu, Y.; Xu, Z.; Xue, L.; Yang, Y.; Yepes, P.; Yi, Y.; Yip, K.; Yoo, I-K.; Zawisza, M.; Zbroszczyk, H.; Zhang, J. B.; Zhang, S.; Zhang, W. M.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.; Zoulkarneeva, Y.; Zyzak, M.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    15 pages, 17 figures, 4 tables. Submitted to Phys. Rev. C ; We report on mid-rapidity mass spectrum of di-electrons and cross sections of pseudoscalar and vector mesons via $e^{+}e^{-}$ decays, from $\sqrt{s} = 200$ GeV $p+p$ collisions, measured by... mehr

     

    15 pages, 17 figures, 4 tables. Submitted to Phys. Rev. C ; We report on mid-rapidity mass spectrum of di-electrons and cross sections of pseudoscalar and vector mesons via $e^{+}e^{-}$ decays, from $\sqrt{s} = 200$ GeV $p+p$ collisions, measured by the large acceptance experiment STAR at RHIC. The ratio of the di-electron continuum to the combinatorial background is larger than 10% over the entire mass range. Simulations of di-electrons from light-meson decays and heavy-flavor decays (charmonium and open charm correlation) are found to describe the data. The extracted $\omega\rightarrow e^{+}e^{-}$ invariant yields are consistent with previous measurements. The mid-rapidity yields ($dN/dy$) of $\phi$ and $J/\psi$ are extracted through their di-electron decay channels and are consistent with the previous measurements of $\phi\rightarrow K^{+}K^{-}$ and $J/\psi\rightarrow e^{+}e^{-}$. Our results suggest a new upper limit of the branching ratio of the $\eta \rightarrow e^{+}e^{-}$ of $1.7\times10^{-5}$ at 90% confidence level.

     
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    Quelle: BASE Fachausschnitt AVL
    Sprache: Englisch
    Medientyp: Aufsatz aus einer Zeitschrift
    Format: Online
    Übergeordneter Titel: ISSN: 2469-9985 ; EISSN: 2469-9993 ; Physical Review C ; http://hal.in2p3.fr/in2p3-00699504 ; Physical Review C, American Physical Society, 2012, 86, pp.024906. ⟨10.1103/PhysRevC.86.024906⟩
    Schlagworte: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  4. Measurement of prompt and non-prompt J/psi production cross sections at mid-rapidity in pp collisions at sqrt(s) = 7 TeV
    Autor*in: Abelev, B.; Aphecetche, Laurent; Baldisseri, A.; Batigne, Guillaume; Belikov, I.; Bergognon, A.A.E.; Borel, H.; Bregant, M.; Castillo Castellanos, J.; Charvet, J.L.; Cheshkov, C.; Cheynis, B.; Delagrange, H.; Driga, O.; Ducroux, L.; Estienne, Magali; Germain, Marie; Grossiord, J.-Y.; Guilbaud, Maxime; Hippolyte, B.; Jangal, S.; Kuhn, C.; Lardeux, A.; Lef'Evre, F.; Lenhardt, M.; Luquin, L.; Martinez Garcia, Gines; Mas, A.; Massacrier, L.; Matyja, A.; Pal, S.; Pereira Da Costa, H.; Pillot, Philippe; Rakotozafindrabe, A.; Roy, C.; Sanchez Castro, X.; Schutz, Y.; Shabetai, Alexandre; Stocco, Diego; Tieulent, R.; Uras, A.; Vernet, R.; Wan, R.; Yang, H.; Zoccarato, Y.; Arbor, N.; Conesa Balbastre, G.; Faivre, J.; Furget, C.; Guernane, R.; Kox, S.; Real, J.S.; Silvestre, C.; Ahn, Sang Un; Baek, Y.W.; Baldit, A.; Barret, V.; Bastid, N.; Crochet, P.; Dupieux, P.; Ichou, R.; Lopez, X.; Manso, F.; Marchisone, M.; Porteboeuf-Houssais, S.; Rosnet, P.; Vulpescu, B.; Zhang, X.
    Erschienen: 2012
    Verlag:  HAL CCSD ; Springer

    see paper for full list of authors ; The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at {\surd}s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L_int =... mehr

     

    see paper for full list of authors ; The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at {\surd}s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L_int = 5.6nb-1. The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum pt > 1.3 GeV/c and rapidity |y| < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the Psi(2S) and Csi_c resonances, is sigma_prompt-J/psi(pt > 1.3 GeV/c, |y| < 0.9) = 7.2 +- 0.7(stat.) +- 1.0(syst.)+1.3-1.2 (syst.pol.) mb. The pt-differential cross section for prompt J/psi has also been measured. The cross section for the production of b-hadrons decaying to J/psi with transverse momentum greater than 1.3 GeV/c in the rapidity range |y| < 0.9 is sigma_{J/psi<-h_B} = 1.26 +- 0.33 (stat.) +0.23-0.28 (syst.) mb. The results are compared to QCD model predictions. The shape of the pt and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the bb pair total cross section and dsigma/dy at midrapidity.

     
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    Quelle: BASE Fachausschnitt AVL
    Sprache: Englisch
    Medientyp: Aufsatz aus einer Zeitschrift
    Format: Online
    Übergeordneter Titel: ISSN: 1126-6708 ; EISSN: 1029-8479 ; Journal of High Energy Physics ; http://hal.in2p3.fr/in2p3-00702009 ; Journal of High Energy Physics, Springer, 2012, 2012, pp.065. &#x27E8;10.1007/JHEP11(2012)065&#x27E9;
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]
  5. Measurement of Direct Photons in Au+Au Collisions at sqrt(s_NN) = 200 GeV
    Autor*in: Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, y.; Al-Jamel, A.; Alexander, J.; Aoki, K.; Aphecetche, Laurent; Armendariz, R.; Aronson, S. H.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Baldisseri, A.; Barish, K. N.; Barnes, P. D.; Bassalleck, B.; Bathe, S.; Batsouli, S.; Baublis, V.; Bauer, F.; Bazilevsky, A.; Belikov, S.; Bennett, R.; Berdnikov, y.; Bjorndal, M. T.; Boissevain, J. G.; Borel, H.; Boyle, K.; Brooks, M. L.; Brown, D. S.; Bucher, D.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Burward-Hoy, J. M.; Butsyk, S.; Campbell, S.; Chai, J. -S.; Chernichenko, S.; Chi, C. y.; Chiba, J.; Chiu, M.; Choi, I. J.; Chujo, T.; Cianciolo, V.; Cleven, C. R.; Cobigo, y.; Cole, B. A.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    PHENIX Collaboration, 346 authors, 8 pages, 4 figures, 1 table. Submitted to Phys. Rev. Lett. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at... mehr

     

    PHENIX Collaboration, 346 authors, 8 pages, 4 figures, 1 table. Submitted to Phys. Rev. Lett. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at www.phenix.bnl.gov/papers.html ; We report the measurement of direct photons at midrapidity in Au+Au collisions at sqrt{s_NN} = 200 GeV. The direct photon signal was extracted for the transverse-momentum range of 4 GeV/c < p_T < 22 GeV/c, using a statistical method to subtract decay photons from the inclusive-photon sample. The direct-photon nuclear-modification factor R_AA was calculated as a function of p_T for different Au+Au collision centralities using the measured p+p direct-photon spectrum and compared to theoretical predictions. R_AA was found to be consistent with unity for all centralities over the entire measured p_T range. Theoretical models that account for modifications of initial-direct-photon production due to modified-parton-distribution functions in Au and the different isospin composition of the nuclei, predict a modest change of R_AA from unity and are consistent with the data. Models with compensating effects of the quark-gluon plasma on high-energy photons, such as suppression of jet-fragmentation photons and induced-photon bremsstrahlung from partons traversing the medium, are also consistent with this measurement.

     
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    Übergeordneter Titel: ISSN: 0031-9007 ; EISSN: 1079-7114 ; Physical Review Letters ; http://hal.in2p3.fr/in2p3-00702413 ; Physical Review Letters, American Physical Society, 2012, 109, pp.152302. &#x27E8;10.1103/PhysRevLett.109.152302&#x27E9;
    Schlagworte: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  6. Once more on the Witten index of 3d supersymmetric YM-CS theory
    Autor*in: Smilga, A. V.
    Erschienen: 2012
    Verlag:  HAL CCSD ; Springer

    27 pages ; The problem of counting the vacuum states in the supersymmetric 3d Yang-Mills-Chern-Simons theory is reconsidered. We resolve the controversy between its original calculation by Witten at large volumes and the calculation based on the... mehr

     

    27 pages ; The problem of counting the vacuum states in the supersymmetric 3d Yang-Mills-Chern-Simons theory is reconsidered. We resolve the controversy between its original calculation by Witten at large volumes and the calculation based on the evaluation of the effective Lagrangian in the small volume limit. We show that the latter calculation suffers from uncertainties associated with the singularities in the moduli space of classical vacua where the Born-Oppenheimer approximation breaks down. We also show that these singularities can be accurately treated in the Hamiltonian Born-Oppenheimer method, where one has to match carefully the effective wave functions on the Abelian valley and the wave functions of reduced non-Abelian QM theory near the singularities. This gives the same result as original Witten's calculation.

     
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    Übergeordneter Titel: ISSN: 1126-6708 ; EISSN: 1029-8479 ; Journal of High Energy Physics ; http://hal.in2p3.fr/in2p3-00702438 ; Journal of High Energy Physics, Springer, 2012, 1205 (2012), pp.103. &#x27E8;10.1007/JHEP05(2012)103&#x27E9;
    Schlagworte: [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th]; [PHYS.MPHY]Physics [physics]/Mathematical Physics [math-ph]; [MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph]
  7. Transverse Single-Spin Asymmetry and Cross-Section for pi0 and eta Mesons at Large Feynman-x in Polarized p+p Collisions at sqrt(s)=200 GeV
    Autor*in: Adamczyk, L.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Alekseev, I.; Alford, J.; Anderson, B. D.; Anson, C. D.; Arkhipkin, D.; Aschenauer, E.; Averichev, G. S.; Balewski, J.; Bannerjee, A.; Barnovska, Z.; Beavis, D. R.; Bellwied, R.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bruna, E.; Bueltmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Cai, X. Z.; Caines, H.; Sánchez, M. Calderón De La Barca; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Chen, Lin; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chung, P.; Chwastowski, J.; Codrington, M. J. M.; Corliss, R.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Leyva, A. Davila; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; De Souza, R. Derradi; Dhamija, S.; Didenko, L.; Ding, F.; Dion, A.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Elnimr, M.; Engelage, J.; Eppley, G.; Eun, L.; Evdokimov, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Fersch, R. G.; Filip, P.; Finch, E.; Fisyak, Y.; Gagliardi, C. A.; Gangadharan, D. R.; Geurts, F.; Gliske, S.; Gorbunov, Y. N.; Grebenyuk, O. G.; Grosnick, D.; Gupta, S.; Guryn, W.; Haag, B.; Hajkova, O.; Hamed, A.; Han, L-X.; Harris, J. W.; Hays-Wehle, J. P.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huck, P.; Humanic, T. J.; Huo, L.; Igo, G.; Jacobs, W. W.; Jena, C.; Joseph, J.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Kettler, D.; Kikola, D. P.; Kiryluk, J.; Kisiel, A.; Kizka, V.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Koroleva, L.; Korsch, W.; Kotchenda, L.; Kravtsov, P.; Krueger, K.; Kumar, L.; Lamont, M. A. C.; Landgraf, J. M.; Lapointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Leight, W.; LeVine, M. J.; Li, C.; Li, L.; Li, W.; Li, Xiaojian; Li, Y.; Li, Z. M.; Lima, L. M.; Lisa, M. A.; Liu, Franklin; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Lu, Y.; Luo, X.; Luszczak, A.; Ma, G. L.; Ma, Y.G.; Don, D. M. M. D. Madagodagettige; Mahapatra, D. P.; Majka, R.; Mall, O. I.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; Mcdonald, D.; McShane, T. S.; Mioduszewski, S.; Mitrovski, M. K.; Mohammed, Y.; Mohanty, B.; Morozov, B.; Munhoz, M. G.; Mustafa, M. K.; Naglis, M.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nogach, L. V.; Novak, J.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Oliveira, R. A. N.; Olson, D.; Ostrowski, P.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Plyku, D.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Powell, C. B.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Redwine, R.; Reed, R.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Ruan, L.; Rusnak, J.; Sahoo, N. R.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, B.; Schmitz, N.; Schuster, T. R.; Seele, J.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shao, M.; Sharma, B.; Sharma, M.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; DeSouza, U. G.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Steadman, S. G.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; De Toledo, A. Szanto; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarini, L. H.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trainor, T. A.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; Van Nieuwenhuizen, G.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Videbaek, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wada, M.; Wang, F.; Wang, Gang; Wang, H.; Wang, J. S.; Wang, Qiang; Wang, X. L.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Whitten Jr, C.; Wieman, H.; Wissink, S. W.; Witt, R.; Witzke, W.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, N.; Xu, Q. H.; Xu, Wei-Jiang; Xu, Y.; Xu, Z.; Xue, L.; Yang, Y.; Yepes, P.; Yi, Y.; Yip, K.; Yoo, I-K.; Zawisza, M.; Zbroszczyk, H.; Zhang, J. B.; Zhang, S.; Zhang, W. M.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.; Zoulkarneeva, Y.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    7 pages, 5 figures, Submitted to Phys. Rev. D R.C ; Measurements of the differential cross-section and the transverse single-spin asymmetry, A_N, vs. x_F for pi0 and eta mesons are reported for 0.4 < x_F < 0.75 at an average pseudorapidity of 3.68. A... mehr

     

    7 pages, 5 figures, Submitted to Phys. Rev. D R.C ; Measurements of the differential cross-section and the transverse single-spin asymmetry, A_N, vs. x_F for pi0 and eta mesons are reported for 0.4 < x_F < 0.75 at an average pseudorapidity of 3.68. A data sample of approximately 6.3 pb^{-1} was analyzed, which was recorded during p+p collisions at sqrt{s} = 200 GeV by the STAR experiment at RHIC. The average transverse beam polarization was 56%. The cross-section for pi0 is consistent with a perturbative QCD prediction, and the eta/pi0 cross-section ratio agrees with previous mid-rapidity measurements. For 0.55 < x_F < 0.75, A_N for eta (0.210 +- 0.056) is 2.2 standard deviations larger than A_N for pi0 (0.081 +- 0.016).

     
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    Übergeordneter Titel: ISSN: 1550-7998 ; EISSN: 1550-2368 ; Physical Review D ; http://hal.in2p3.fr/in2p3-00703157 ; Physical Review D, American Physical Society, 2012, 86, pp.051101. &#x27E8;10.1103/PhysRevD.86.051101&#x27E9;
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]; [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  8. Direct-Photon Production in p+p Collisions at sqrt(s)=200 GeV at Midrapidity
    Autor*in: Adare, A.; Aphecetche, Laurent; Atomssa, E. T.; Baldisseri, A.; Borel, H.; Charvet, J. -L.; Dahms, T.; d'Enterria, D.; Drapier, O.; Fleuret, F.; Gonin, M.; Gosset, J.; de Cassagnac, R. Granier; Henni, A. Hadj; Jouan, D.; Lenzi, B.; Nguyen, M.; Pereira, H.; Rakotozafindrabe, A.; Roche, G.; Rosnet, P.; Silvestre, C.; Staley, F.; Suire, C.; Tram, V-N.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    See paper for full list of authors ; PHENIX Collaboration, 383 authors, 16 pages, 14 figures, 7 tables. Submitted to Phys. Rev. D. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be)... mehr

     

    See paper for full list of authors ; PHENIX Collaboration, 383 authors, 16 pages, 14 figures, 7 tables. Submitted to Phys. Rev. D. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at www.phenix.bnl.gov/papers.html ; The differential cross section for the production of direct photons in p+p collisions at sqrt(s)=200 GeV at midrapidity was measured in the PHENIX detector at the Relativistic Heavy Ion Collider. Inclusive-direct photons were measured in the transverse-momentum range from 5.5--25 GeV/c, extending the range beyond previous measurements. Event structure was studied with an isolation criterion. Next-to-leading-order perturbative-quantum-chromodynamics calculations give a good description of the spectrum. When the cross section is expressed versus x_T, the PHENIX data are seen to be in agreement with measurements from other experiments at different center-of-mass energies.

     
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    Übergeordneter Titel: ISSN: 1550-7998 ; EISSN: 1550-2368 ; Physical Review D ; https://hal.in2p3.fr/in2p3-00703928 ; Physical Review D, American Physical Society, 2012, 86, pp.072008. &#x27E8;10.1103/PhysRevD.86.072008&#x27E9;
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]; [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  9. Measurement of charm production at central rapidity in proton-proton collisions at sqrt(s) = 2.76 TeV
    Autor*in: Abelev, B.; Vernet, R.; Belikov, I.; Hippolyte, B.; Jangal, S.; Kuhn, C.; Roy, C.; Sanchez Castro, X.; Senyukov, S.; Wan, R.; Aphecetche, Laurent; Batigne, Guillaume; Bergognon, E.; Bregant, M.; Delagrange, H.; Driga, O.; Estienne, Magali; Germain, Marie; Lardeux, A.; Lefèvre, F.; Lenhardt, M.; Luquin, L.; Martinez Garcia, Gines; Mas, A.; Massacrier, L.; Matyja, A.; Pillot, Philippe; Schutz, y.; Shabetai, Alexandre; Stocco, Diego; Cheshkov, C.; Cheynis, B.; Ducroux, L.; Grossiord, J.-y.; Guilbaud, Maxime; Tieulent, R.; Uras, A.; Zoccarato, y.; Ahn, Sang Un; Baek, y.W.; Baldit, A.; Barret, V.; Bastid, N.; Crochet, P.; Dupieux, P.; Ichou, R.; Lopez, X.; Manso, F.; Marchisone, M.; Porteboeuf-Houssais, S.
    Erschienen: 2012
    Verlag:  HAL CCSD ; Springer

    See paper for full list of authors ; The pt-differential production cross sections of the prompt (B feed-down subtracted) charmed mesons D0, D+, and D*+ in the rapidity range |y|<0.5, and for transverse momentum 1< pt <12 GeV/c, were measured in... mehr

     

    See paper for full list of authors ; The pt-differential production cross sections of the prompt (B feed-down subtracted) charmed mesons D0, D+, and D*+ in the rapidity range |y|<0.5, and for transverse momentum 1< pt 12 GeV/c, were measured in proton-proton collisions at sqrt(s) = 2.76 TeV with the ALICE detector at the Large Hadron Collider. The analysis exploited the hadronic decays D0 -> K pi, D+ -> K pi pi, D*+ -> D0 pi, and their charge conjugates, and was performed on a L_{int} = 1.35 nb^{-1} event sample collected in 2011 with a minimum-bias trigger. The total charm production cross section at sqrt(s) = 2.76 TeV and at 7 TeV was evaluated by extrapolating to the full phase space the pt-differential production cross sections at sqrt(s) = 2.76 TeV and our previous measurements at sqrt(s) = 7 TeV. The results were compared to existing measurements and to perturbative-QCD calculations. The fraction of cubar D mesons produced in a vector state was also determined.

     
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    Übergeordneter Titel: ISSN: 1126-6708 ; EISSN: 1029-8479 ; Journal of High Energy Physics ; http://hal.in2p3.fr/in2p3-00705656 ; Journal of High Energy Physics, Springer, 2012, 7, pp.191. &#x27E8;10.1007/JHEP07(2012)191&#x27E9;
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]; [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  10. K0s-K0s correlations in pp collisions at sqrt{s}=7 TeV from the LHC ALICE experiment
    Autor*in: Abelev, B.; Arbor, N.; Conesa Balbastre, G.; Faivre, J.; Furget, C.; Guernane, R.; Kox, S.; Real, J.S.; Silvestre, C.; Vernet, R.; Belikov, I.; Hippolyte, B.; Kuhn, C.; Roy, C.; Sanchez Castro, X.; Senyukov, S.; Aphecetche, Laurent; Batigne, Guillaume; Bergognon, E.; Bregant, M.; Delagrange, H.; Driga, O.; Estienne, Magali; Germain, Marie; Lardeux, A.; Lefèvre, F.; Lenhardt, M.; Luquin, L.; Martinez Garcia, Gines; Mas, A.; Massacrier, L.; Matyja, A.; Pillot, Philippe; Schutz, Y.; Shabetai, Alexandre; Stocco, Diego; Ahn, Sang Un; Baek, Y.W.; Baldit, A.; Barret, V.; Bastid, N.; Crochet, P.; Dupieux, P.; Ichou, R.; Lopez, X.; Manso, F.; Marchisone, M.; Porteboeuf-Houssais, S.; Rosnet, P.; Vulpescu, B.
    Erschienen: 2012
    Verlag:  HAL CCSD ; Elsevier

    See paper for full list of authors - 10 pages + author list, 7 figures, to be submitted to Physics Letters B ; Identical neutral kaon pair correlations are measured in sqrt{s}=7 TeV pp collisions in the ALICE experiment. One-dimensional K0s-K0s... mehr

     

    See paper for full list of authors - 10 pages + author list, 7 figures, to be submitted to Physics Letters B ; Identical neutral kaon pair correlations are measured in sqrt{s}=7 TeV pp collisions in the ALICE experiment. One-dimensional K0s-K0s correlation functions in terms of the invariant momentum difference of kaon pairs are formed in two multiplicity and two transverse momentum ranges. The femtoscopic parameters for the radius and correlation strength of the kaon source are extracted. The fit includes quantum statistics and final-state interactions of the a0/f0 resonance. K0s-K0s correlations show an increase in radius for increasing multiplicity and a slight decrease in radius for increasing transverse mass, mT, as seen in pion-pion correlations in the pp system and in heavy-ion collisions. Transverse mass scaling is observed between the K0s-K0s and pion-pion radii. Also, the first observation is made of the decay of the f2'(1525) meson into the K0s-K0s channel in pp collisions.

     
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    Übergeordneter Titel: ISSN: 0370-2693 ; Physics Letters B ; https://hal.in2p3.fr/in2p3-00707149 ; Physics Letters B, Elsevier, 2012, 717, pp.151-161. &#x27E8;10.1016/j.physletb.2012.09.013&#x27E9;
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]; [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  11. Inclusive charged hadron elliptic flow in Au + Au collisions at $\sqrt{s_{NN}}$ = 7.7 - 39 GeV
    Autor*in: Adamczyk, L.; Borowski, W.; Kabana, S.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    19 pages, 11 figures ; see paper for full list of authors ; A systematic study is presented for centrality, transverse momentum ($p_T$) and pseudorapidity ($\eta$) dependence of the inclusive charged hadron elliptic flow ($v_2$) at midrapidity... mehr

     

    19 pages, 11 figures ; see paper for full list of authors ; A systematic study is presented for centrality, transverse momentum ($p_T$) and pseudorapidity ($\eta$) dependence of the inclusive charged hadron elliptic flow ($v_2$) at midrapidity ($|\eta| < 1.0$) in Au+Au collisions at $\sqrt{s_{NN}}$ = 7.7, 11.5, 19.6, 27 and 39 GeV. The results obtained with different methods, including correlations with the event plane reconstructed in a region separated by a large pseudorapidity gap, and 4-particle cumulants ($v_2\{4\}$), are presented in order to investigate non-flow correlations and $v_2$ fluctuations. We observe that the difference between $v_2\{2\}$ and $v_2\{4\}$ is smaller at the lower collision energies. Values of $v_2$, scaled by the initial coordinate space eccentricity, $v_{2}/\varepsilon$, as a function of $p_T$ are larger in more central collisions, suggesting stronger collective flow develops in more central collisions, similar to the results at higher collision energies. These results are compared to measurements at higher energies at RHIC ($\sqrt{s_{NN}}$ = 62.4 and 200 GeV) and at LHC (Pb + Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV). The $v_2(p_T)$ values for fixed $p_T$ rise with increasing collision energy within the $p_T$ range studied ($< 2 {\rm GeV}/c$). We compare the $v_2$ results to UrQMD and AMPT transport model calculations, and physics implications on the dominance of partonic versus hadronic phases in the system created at BES energies are discussed.

     
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    Übergeordneter Titel: ISSN: 2469-9985 ; EISSN: 2469-9993 ; Physical Review C ; http://hal.in2p3.fr/in2p3-00711874 ; Physical Review C, American Physical Society, 2012, 86, pp.054908. &#x27E8;10.1103/PhysRevC.86.054908&#x27E9;
    Schlagworte: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  12. Search for Point-like Sources of Ultra-high Energy Neutrinos at the Pierre Auger Observatory and Improved Limit on the Diffuse Flux of Tau Neutrinos
    Autor*in: Abreu, P.; Aglietta, M.; Ahlers, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Alves Batista, R.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antičic, T.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Badescu, A. M.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Bäuml, J.; Baus, C.; Beatty, J. J.; Becker, K. H.; Bellétoile, A.; Bellido, J. A.; Benzvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanch-Bigas, O.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.
    Erschienen: 2012
    Verlag:  HAL CCSD ; Bristol : IOP Publishing

    See paper for full list of authors ; The surface detector array of the Pierre Auger Observatory can detect neutrinos with energy E ν between 1017 eV and 1020 eV from point-like sources across the sky south of +55° and north of -65° declinations. A... mehr

     

    See paper for full list of authors ; The surface detector array of the Pierre Auger Observatory can detect neutrinos with energy E ν between 1017 eV and 1020 eV from point-like sources across the sky south of +55° and north of -65° declinations. A search has been performed for highly inclined extensive air showers produced by the interaction of neutrinos of all flavors in the atmosphere (downward-going neutrinos), and by the decay of tau leptons originating from tau neutrino interactions in Earth's crust (Earth-skimming neutrinos). No candidate neutrinos have been found in data up to 2010 May 31. This corresponds to an equivalent exposure of ~3.5 years of a full surface detector array for the Earth-skimming channel and ~2 years for the downward-going channel. An improved upper limit on the diffuse flux of tau neutrinos has been derived. Upper limits on the neutrino flux from point-like sources have been derived as a function of the source declination. Assuming a differential neutrino flux k PS * E -2 ν from a point-like source, 90% confidence level upper limits for k PS at the level of ≈5 × 10-7 and 2.5 × 10-6 GeV cm-2 s-1 have been obtained over a broad range of declinations from the searches for Earth-skimming and downward-going neutrinos, respectively.

     
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    Übergeordneter Titel: ISSN: 2041-8205 ; EISSN: 2041-8213 ; The Astrophysical journal letters ; https://hal.in2p3.fr/in2p3-00720606 ; The Astrophysical journal letters, 2012, 755, pp.L4. &#x27E8;10.1088/2041-8205/755/1/L4&#x27E9;
    Schlagworte: astroparticle physics; cosmic rays; neutrinos; telescopes; [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]; [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]; [PHYS]Physics [physics]; [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
  13. Interactions between Nuclear Fuel and Water at the Fukushima Daiichi Reactors
    Autor*in: Grambow, Bernd; Poinssot, C.
    Erschienen: 2012
    Verlag:  HAL CCSD ; GeoScienceWorld

    Used nuclear fuel is a redox-sensitive semiconductor consisting of uranium dioxide containing a few percent of fission products and up to about one percent transuranium elements, mainly plutonium. The rapid increase in temperature in the cores of the... mehr

     

    Used nuclear fuel is a redox-sensitive semiconductor consisting of uranium dioxide containing a few percent of fission products and up to about one percent transuranium elements, mainly plutonium. The rapid increase in temperature in the cores of the Fukushima reactors was caused by the loss of coolant in the aftermath of the damage from the tsunami. Temperatures probably well above 2000 °C caused melting of not only the UO2 in the fuel but also the zircaloy cladding and steel, forming a quenched melt, termed corium. Substantial amounts of volatile fission products, such as Cs and I, were released during melting, but the less volatile fission products and the actinides (probably >99.9%) were incorporated into the corium as the melt cooled and was quenched. The corium still contains these radionuclides, which leads to a very large long-term radiotoxicity of the molten reactor core. The challenge for environmental scientists is to assess the long-term interactions between water and the mixture of corium and potentially still-existing unmelted fuel, particularly if the molten reactor core is left in place and covered with a sarcophagus for hundreds of years. Part of the answer to this question can be found in the knowledge that has been gained from research into the disposal of spent nuclear fuel in a geologic repository.

     
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    Übergeordneter Titel: ISSN: 1811-5209 ; EISSN: 1811-5217 ; Elements ; http://hal.in2p3.fr/in2p3-00721815 ; Elements, GeoScienceWorld, 2012, 8, pp.213-219. &#x27E8;10.2113/gselements.8.3.213&#x27E9;
    Schlagworte: corium; spent fuel; radionuclide release; environmental impact; radiotoxicity; Fukushima Daiichi nuclear power plant; [CHIM.RADIO]Chemical Sciences/Radiochemistry; [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
  14. Direct photon production in d+Au collisions at sqrt(s_NN)=200 GeV at midrapidity
    Autor*in: Adare, A.; Atomssa, E. T.; Baldisseri, A.; Borel, H.; Camard, Xavier; Charvet, J. -L.; Cobigo, Y.; Cussonneau, Jean-Pierre; Dahms, T.; Delagrange, Hugues; Drapier, O.; Finck, C.; Fleuret, F.; Gadrat, S.; Gonin, M.; Gosset, J.; De Cassagnac, R. Granier; Henni, Ahmed Hadj; Lenzi, B.; Martinez Garcia, Gines; Nguyen, M.; Pereira, H.; Rakotozafindrabe, A.; Roche, G.; Rosnet, P.; Schutz, Yves; Staley, F.; Tram, V-N.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    see paper for full list of authors - 547 authors, 7 pages, 4 figures. Submitted to Phys. Rev. Lett. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at... mehr

     

    see paper for full list of authors - 547 authors, 7 pages, 4 figures. Submitted to Phys. Rev. Lett. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at www.phenix.bnl.gov/papers.html ; The differential cross section for the production of direct photons in p+p collisions at √s=200 GeV at midrapidity was measured in the PHENIX detector at the Relativistic Heavy Ion Collider. Inclusive direct photons were measured in the transverse momentum range from 5.5-25 GeV/c, extending the range beyond previous measurements. Event structure was studied with an isolation criterion. Next-to-leading-order perturbative-quantum-chromodynamics calculations give a good description of the spectrum. When the cross section is expressed versus xT, the PHENIX data are seen to be in agreement with measurements from other experiments at different center-of-mass energies.

     
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    Übergeordneter Titel: ISSN: 1550-7998 ; EISSN: 1550-2368 ; Physical Review D ; http://hal.in2p3.fr/in2p3-00723336 ; Physical Review D, American Physical Society, 2012, 86, pp.072008. &#x27E8;10.1103/PhysRevD.86.072008&#x27E9;
    Schlagworte: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  15. Deviation from quark number scaling of the anisotropy parameter v2 of pions, kaons, and protons in Au+Au collisions at √sNN=200 GeV
    Autor*in: Adare, A.; Aphecetche, Laurent; T. Atomssa, E.; Baldisseri, A.; Borel, H.; L. Charvet, J.; Dahms, T.; d'Enterria, D.; Drapier, O.; Fleuret, F.; Gonin, M.; Gosset, J.; Granier de Cassagnac, R.; Hadj Henni, A.; Jouan, D.; Lenzi, B.; Nguyen, M.; Pereira, H.; Rakotozafindrabe, A.; Roche, G.; Rosnet, P.; Silvestre, C.; Staley, F.; Suire, C.; Tram, V.-N.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    See paper for full list of authors ; Measurements of the anisotropy parameter v2 of identified hadrons (pions, kaons, and protons) as a function of centrality, transverse momentum pT, and transverse kinetic energy KET at midrapidity (|η|<0.35) in Au... mehr

     

    See paper for full list of authors ; Measurements of the anisotropy parameter v2 of identified hadrons (pions, kaons, and protons) as a function of centrality, transverse momentum pT, and transverse kinetic energy KET at midrapidity (|η|<0.35) in Au + Au collisions at √sNN=200 GeV are presented. Pions and protons are identified up to pT= 6 GeV/c, and kaons up to pT= 4 GeV/c, by combining information from time-of-flight and aerogel Čerenkov detectors in the PHENIX Experiment. The scaling of v2 with the number of valence quarks (nq) has been studied in different centrality bins as a function of transverse momentum and transverse kinetic energy. A deviation from previously observed quark-number scaling is observed at large values of KET/nq in noncentral Au + Au collisions (20-60%), but this scaling remains valid in central collisions (0-10%).

     
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    Übergeordneter Titel: ISSN: 2469-9985 ; EISSN: 2469-9993 ; Physical Review C ; http://hal.in2p3.fr/in2p3-00724075 ; Physical Review C, American Physical Society, 2012, 85, pp.064914. &#x27E8;10.1103/PhysRevC.85.064914&#x27E9;
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]; [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  16. Radiative energy loss in the absorptive QGP: taming the long formation lengths in coherent emission
    Autor*in: Bluhm, M.; Gossiaux, Pol-Bernard; Gousset, Thierry; Aichelin, Joerg
    Erschienen: 2012
    Verlag:  HAL CCSD

    contribution to the International Meeting "Excited QCD", Peniche, Portugal, 06 - 12 May 2012 ; In an absorptive plasma, damping of radiation mechanisms can influence the bremsstrahlung formation in case of large radiation formation lengths. We study... mehr

     

    contribution to the International Meeting "Excited QCD", Peniche, Portugal, 06 - 12 May 2012 ; In an absorptive plasma, damping of radiation mechanisms can influence the bremsstrahlung formation in case of large radiation formation lengths. We study qualitatively the influence of this effect on the gluon bremsstrahlung spectrum off heavy quarks in the quark-gluon plasma. Independent of the heavy-quark mass, the spectrum is found to be strongly suppressed in an intermediate gluon energy region which grows with increasing gluon damping rate and increasing energy of the heavy quark. Thus, just as polarization effects in the plasma render the bremsstrahlung spectra independent of the quark mass in the soft gluon regime, damping effects tend to have a similar impact for larger gluon energies.

     
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    Übergeordneter Titel: Excited QCD 2012 ; http://hal.in2p3.fr/in2p3-00730449 ; Excited QCD 2012, May 2012, Peniche, Portugal
    Schlagworte: [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]; [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th]
  17. J/psi elliptic flow measurement in Pb-Pb collisions at \sqrt{s_{NN}} = 2.76 TeV at forward rapidity with the ALICE experiment
    Autor*in: Massacrier, L.
    Erschienen: 2012
    Verlag:  HAL CCSD

    proceeding of Hard Probes 2012 conference ; J/psi suppression induced by color screening of its constituent quarks was proposed 26 years ago as a signature of the formation of a quark gluon plasma in heavy-ion collisions. Recent results from ALICE in... mehr

     

    proceeding of Hard Probes 2012 conference ; J/psi suppression induced by color screening of its constituent quarks was proposed 26 years ago as a signature of the formation of a quark gluon plasma in heavy-ion collisions. Recent results from ALICE in Pb-Pb collisions exhibit a smaller suppression with respect to previous measurements at the SPS and RHIC. The study of azimuthal anisotropy in particle production gives information on the collective hydrodynamic expansion at the early stage of the fireball, where the matter created in high-energy nuclear collisions is expected to be in a deconfined state. In particular, J/psi elliptic flow v2 is important to test the degree of thermalization of heavy quarks. Together with the production yields, the elliptic flow is a powerful observable to address the question of suppression and regeneration of J/psi in QGP. We present the first inclusive J/psi elliptic flow measurement performed with the muon spectrometer of ALICE, in Pb-Pb collisions, at forward rapidity. Integrated and pT-differential v2 results are presented and a comparison with recent STAR results and with a parton transport model is also performed.

     
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    Übergeordneter Titel: Hard Probes 2012 ; http://hal.in2p3.fr/in2p3-00730928 ; Hard Probes 2012, May 2012, Cagliari, Italy
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]; [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  18. New antineutrino energy spectra predictions from the summation of beta decay branches of the fission products
    Autor*in: Fallot, Muriel; Cormon, S.; Estienne, Magali; Algora, A.; Bui, Van Minh; Cucoanes, A.; Elnimr, M.; Giot, Lydie; Jordan, D.; Martino, J.; Onillon, A.; Porta, Amanda; Pronost, G.; Remoto, A.; Taín, J.L.; Yermia, Frédéric; Zakari-Issoufou, A.-A.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    10 pages, 2 figures ; In this paper, we study the impact of the inclusion of the recently measured beta decay properties of the $^{102;104;105;106;107}$Tc, $^{105}$Mo, and $^{101}$Nb nuclei in an updated calculation of the antineutrino energy spectra... mehr

     

    10 pages, 2 figures ; In this paper, we study the impact of the inclusion of the recently measured beta decay properties of the $^{102;104;105;106;107}$Tc, $^{105}$Mo, and $^{101}$Nb nuclei in an updated calculation of the antineutrino energy spectra of the four fissible isotopes $^{235, 238}$U, and $^{239,241}$Pu. These actinides are the main contributors to the fission processes in Pressurized Water Reactors. The beta feeding probabilities of the above-mentioned Tc, Mo and Nb isotopes have been found to play a major role in the $\gamma$ component of the decay heat of $^{239}$Pu, solving a large part of the $\gamma$ discrepancy in the 4 to 3000\,s range. They have been measured using the Total Absorption Technique (TAS), avoiding the Pandemonium effect. The calculations are performed using the information available nowadays in the nuclear databases, summing all the contributions of the beta decay branches of the fission products. Our results provide a new prediction of the antineutrino energy spectra of $^{235}$U, $^{239,241}$Pu and in particular of $^{238}$U for which no measurement has been published yet. We conclude that new TAS measurements are mandatory to improve the reliability of the predicted spectra.

     
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    Übergeordneter Titel: ISSN: 0031-9007 ; EISSN: 1079-7114 ; Physical Review Letters ; http://hal.in2p3.fr/in2p3-00734002 ; Physical Review Letters, American Physical Society, 2012, 109, pp.202504. &#x27E8;10.1103/PhysRevLett.109.202504&#x27E9;
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]; [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]; [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  19. Inclusive cross section and single-transverse-spin asymmetry for very forward neutron production in polarized p+p collisions at sqrt(s)=200 GeV
    Autor*in: Adare, A.; Aphecetche, Laurent; Hadj Henni, A.; Atomssa, E. T.; D'Enterria, D.; Drapier, O.; Fleuret, F.; Gonin, M.; Granier De Cassagnac, R.; Rakotozafindrabe, A.; Tram, V.-N.; Roche, G.; Rosnet, P.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    see paper for full list of authors - 383 authors, 16 pages, 18 figures, 6 tables. Submitted to Phys. Rev. D. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at... mehr

     

    see paper for full list of authors - 383 authors, 16 pages, 18 figures, 6 tables. Submitted to Phys. Rev. D. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at www.phenix.bnl.gov/papers.html ; The energy dependence of the single-transverse-spin asymmetry, A_N, and the cross section for neutron production at very forward angles were measured in the PHENIX experiment at RHIC for polarized p+p collisions at sqrt(s)=200 GeV. The neutrons were observed in forward detectors covering an angular range of up to 2.2 mrad. We report results for neutrons with momentum fraction of x_F=0.45 to 1.0. The energy dependence of the measured cross sections were consistent with x_F scaling, compared to measurements by an ISR experiment which measured neutron production in unpolarized p+p collisions at sqrt(s)=30.6--62.7 GeV. The cross sections for large x_F neutron production for p+p collisions, as well as those in e+p collisions measured at HERA, are described by a pion exchange mechanism. The observed forward neutron asymmetries were large, reaching A_N=-0.08+/-0.02 for x_F=0.8; the measured backward asymmetries, for negative x_F, were consistent with zero. The observed asymmetry for forward neutron production is discussed within the pion exchange framework, with interference between the spin-flip amplitude due to the pion exchange and nonflip amplitudes from all Reggeon exchanges. Within the pion exchange description, the measured neutron asymmetry is sensitive to the contribution of other Reggeon exchanges even for small amplitudes.

     
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    Übergeordneter Titel: ISSN: 1550-7998 ; EISSN: 1550-2368 ; Physical Review D ; http://hal.in2p3.fr/in2p3-00734009 ; Physical Review D, American Physical Society, 2012, 88, pp.032006. &#x27E8;10.1103/PhysRevD.88.032006&#x27E9;
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]; [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  20. Erratum: Measurement of transverse single-spin asymmetries for J/psi production in polarized p+p collisions at sqrt(s)=200 GeV [Phys. Rev. D 82, 112008 (2010)]
    Autor*in: Adare, A.; Aphecetche, Laurent; Atomssa, E. T.; Baldisseri, A.; Borel, H.; Charvet, J. -L.; del Valle, Z. Conesa; Dahms, T.; Drapier, O.; Fleuret, F.; Gonin, M.; Gosset, J.; de Cassagnac, R. Granier; Henni, A. Hadj; Jouan, D.; Nguyen, M.; Pereira, H.; Rakotozafindrabe, A.; Tram, V-N.; Roche, G.; Rosnet, P.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    431 authors from 62 institutions, 3 pages, 2 figures, and 3 tables. Erratum submitted to Physical Review D, see paper for full list of authors ; International audience ; We previously reported [Phys. Rev. D 82, 112008 (2010)] measurements of... mehr

     

    431 authors from 62 institutions, 3 pages, 2 figures, and 3 tables. Erratum submitted to Physical Review D, see paper for full list of authors ; International audience ; We previously reported [Phys. Rev. D 82, 112008 (2010)] measurements of transverse single-spin asymmetries, A_N, in J/psi production from transversely polarized p+p collisions at sqrt(s)=200 GeV with data taken by the PHENIX experiment at the Relativistic Heavy Ion Collider in 2006 and 2008. Subsequently, we have found errors in the analysis procedures for the 2008 data, which resulted in an erroneous value for the extracted A_N. The errors affected the sorting of events into the correct left/right and forward/backward bins. This produced an incorrect value for the 2008 result, but the 2006 result is unaffected. We have conducted two independent reanalyses with these errors corrected, and we present here the corrected values for the 2008 data and the combined results for 2006 and 2008. The new combined spin asymmetry in the forward region is A_N = -0.026+/-0.026(stat)+/-0.003(sys). Since this asymmetry is consistent with zero, we no longer claim that our results suggest a possible non-zero trigluon correlation function in transversely polarized protons.

     
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    Übergeordneter Titel: ISSN: 1550-7998 ; EISSN: 1550-2368 ; Physical Review D ; https://hal.in2p3.fr/in2p3-00745786 ; Physical Review D, American Physical Society, 2012, 86, pp.099904. &#x27E8;10.1103/PhysRevD.86.099904&#x27E9;
    Schlagworte: [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]
  21. Upsilon (1S+2S+3S) production in d+Au and p+p collisions at sqrt(s_NN)=200 GeV and cold-nuclear matter effects
    Autor*in: Adare, A.; Atomssa, E. T.; Conesa del Valle, Z.; d'Enterria, D.; Drapier, O.; Fleuret, F.; Gonin, M.; Granier de Cassagnac, R.; Rakotozafindrabe, A.; Tram, V.N.; Aphecetche, Laurent; Hadj Henni, A.; Roche, G.; Rosnet, P.; Jouan, D.
    Erschienen: 2012
    Verlag:  HAL CCSD ; American Physical Society

    see paper for full list of authors, 495 authors, 11 pages, 9 figures, 5 tables. Submitted to Phys. Rev. C. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at... mehr

     

    see paper for full list of authors, 495 authors, 11 pages, 9 figures, 5 tables. Submitted to Phys. Rev. C. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at www.phenix.bnl.gov/papers.html ; The three Upsilon states, Upsilon(1S+2S+3S), are measured in d+Au and p+p collisions at sqrt(s_NN)=200 GeV and rapidities 1.2<|y|<2.2 by the PHENIX experiment at the Relativistic Heavy-Ion Collider. Cross sections for the inclusive Upsilon(1S+2S+3S) production are obtained. The inclusive yields per binary collision for d+Au collisions relative to those in p+p collisions (R_dAu) are found to be 0.62 +/- 0.26 (stat) +/- 0.13 (syst) in the gold-going direction and 0.91 +/- 0.33 (stat) +/- 0.16 (syst) in the deuteron-going direction. The measured results are compared to a nuclear-shadowing model, EPS09 [JHEP 04, 065 (2009)], combined with a final-state breakup cross section, sigma_br, and compared to lower energy p+A results. We also compare the results to the PHENIX J/psi results [Phys. Rev. Lett. 107, 142301 (2011)]. The rapidity dependence of the observed Upsilon suppression is consistent with lower energy p+A measurements.

     
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    Übergeordneter Titel: ISSN: 0031-9007 ; EISSN: 1079-7114 ; Physical Review Letters ; http://hal.in2p3.fr/in2p3-00756698 ; Physical Review Letters, American Physical Society, 2012, 109, pp.242301. &#x27E8;10.1103/PhysRevLett.109.242301&#x27E9;
    Schlagworte: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]
  22. Molecular modeling of the swelling properties and interlayer structure of Cs, Na, K-Montmorillonite: Effects of charge distribution in the clay layers
    Autor*in: Ngouana Wakou, Brice,; Kalinichev, Andrey G.
    Erschienen: 2012
    Verlag:  HAL CCSD

    Safe and sustainable management of nuclear waste poses major scientific challenges to make the environmental footprint of nuclear energy as small as possible for very long periods of time. As many other countries, France is considering the deep... mehr

     

    Safe and sustainable management of nuclear waste poses major scientific challenges to make the environmental footprint of nuclear energy as small as possible for very long periods of time. As many other countries, France is considering the deep geological disposal (in the Callovo-Oxfordian (COx) argillite formations of the Paris basin) as a reliable way of storing high-level radioactive waste in order to provide adequate protection for humans and the environment. In addition to being proven geologically stable for million years, the natural and engineered clay barriers can benefit from many favorable properties, such as low permeability, high sorption capacity, etc. The mineralogical composition of the Callovo-Oxfordian argillite shows about 41% of clay minerals (23% of interstratified illite/smectite, 14% of illite-type minerals, 2% kaolinite and 2% chlorite) [1,2]. A non-negligible amount of organic matter is also present (~1%) [3], and it is known that the interaction of natural organic matter (NOM) with radionuclides and clays can affect the solubility and toxicity of trace elements in natural aqueous environments [4,5]. Reliable prediction of the behaviour of radionuclides and their transport and retention in clayey formations at nuclear waste repositories requires detailed molecular scale understanding of these complex multicomponent systems. Computational molecular modelling has already become an important tool in the study of thermodynamic, structural and transport properties of hydrated clays (e.g., [6-8]). As the first step in our study of the effects of organic molecules on the adsorption and transport of radionuclides in hydrated clay systems we have investigated the effects of the ordering in charge distributions on the swelling behavior of simulated clays. Montmorillonite was chosen as a model of smectite clay. Montmorillonite structure consists of aluminum-oxygen octahedral sheet sandwiched between two opposing silicon-oxygen tetrahedral sheets giving rise to a 2:1 clay mineral. Isomorphic substitutions in the tetrahedral and octahedral sheets are responsible of the negative layer charge of montmorillonite clay minerals having the chemical composition (Si8-xXx)(Al4-yYy)O20(OH)4 where X = Al, Y = Mg, Fe.[9]. The montmorillonite models for our study are based on a pyrophillite unit cell structure (5.16Å×8.966Å×9.347Å) obtained from the crystallographic data of Lee et al. [10]. The 4×4×2 simulation supercells were built and substitutions were made in the pyrophillite structure in order to approximate as close as possible the chemical composition of Wyoming montmorillonite M24(Si248Al8)(Al112Mg16)O640(OH)128, where M is either Cs+, Na+, or K+ [9]. We explored three different models of substitution distributions. In the first model, the substitutions were uniformly and orderly distributed within the tetrahedral and octahedral sheets. In the second model, the substituted positions were kept ordered in the octahedral sheets but made disordered in the tetrahedral one. In the third model, the substituted positions of the octahedral sites were additionally made disordered. In order to study the swelling behavior of these montmorillonites, molecular dynamics (MD) simulations were run in the NPzT statistical ensemble (T = 298 K, Pz = 1 bar) for each of the three different substitution models and with 22 different hydration states ranging from 0 to 700 mgwater/gclay (from 0 to 42 H2O molecules per one monovalent cation). All MD runs were performed for a total of 2 ns using the CLAYFF force field [11]. At the beginning of the simulations, the cations were placed at the midplane of the clay interlayer space and water molecules were added randomly. After the system reached equilibrium, the last 1ns of each MD trajectory was used to compute the clay basal spacing and the swelling thermodynamic properties: hydration energy, immersion energy, isosteric heat of adsorption. The MD simulation results indicate that in addition to the commonly observed 1-layer and 2-layer hydrates, stable hydration states corresponding to 3-layer and 4-layer hydrates can also be distinguished. The stable states corresponding to the minima of hydration energy were then selected to run further 500 ps NVT-ensemble MD simulations at the same temperature and with the volume fixed at the average value resulting from the corresponding previous NPzT simulation. The equilibrium parts of these NVT-simulated trajectories were then used to calculate the structural (radial distribution functions, atomic density profiles) and dynamical (diffusion coefficient) properties of the hydrated montmorillonite. References [1] ERM (1997) Echantillons d'argiles du forage EST104 : Etude minéralogique approfondie. Rapport ANDRA n° D.RP.0ERM.97.008 [2] ERM (1996b) Caractérisation d'échantillons d'argiles du forage EST103. Rapport ANDRA n° B.RP.0ERM.96.003 [3] ANDRA (2005) Dossier 2005 Argile, Référentiel du site de Meuse Haute Marne. C.R.P.ADS.04.0022 Andra : Paris [4] Buffle, J. (1988) Complexation Reactions in Aquatic Systems: An Analytical Approach; Ellis Horwood Ltd.:Chichester, p 692. [5] Tipping, E. (2002) Cation Binding by Humic Substances, Cambridge University Press: Cambridge, p 434. [6] Smith, D.E., Langmuir, 14, 5959-5967 (1998). [7] Rotenberg, B., Marry, V., Vuilleumier, R., Malikova, N., Simon, C., Turq, P., Geochim. Cosmochim. Acta, 71, 5089-5101 (2007). [8] Liu, X.D., Lu, X.C., Wang, R.C., Zhou, H.Q. Geochim. Cosmochim. Acta, 72, 1837-1847 (2008). [9] Tsipursky, S.I., Drits, V.A. Clay Minerals, 19, 177-193 (1984). [10] Lee, J.H. and Guggenheim, S. American Mineralogist, 66, 350-357 (1981). [11] Cygan, R.T., Liang, J.J., Kalinichev, A.G. Journal of Physical Chemistry B, 108, 1255-1266 (2004).

     
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    Übergeordneter Titel: 5th International meeting "Clays in Natural and Engineered Barriers for Radioactive Waste Confinement" ; http://hal.in2p3.fr/in2p3-00769152 ; 5th International meeting "Clays in Natural and Engineered Barriers for Radioactive Waste Confinement", Oct 2012, Montpellier, France
    Schlagworte: [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry; [CHIM.MATE]Chemical Sciences/Material chemistry; [SDE.IE]Environmental Sciences/Environmental Engineering; [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry; [SDE.MCG]Environmental Sciences/Global Changes; [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
  23. Effects of surface cations on the structure and dynamics of the hydrogen-bonding network at the illite-water interface: A molecular dynamics simulation study
    Autor*in: Narasimhan, L.; Kalinichev, Andrey G.
    Erschienen: 2012
    Verlag:  HAL CCSD

    Safe and sustainable management of nuclear energy poses major scientific and engineering challenges, one of which is the necessity to make the environmental impacts of the long-term nuclear waste storage as small as possible. This requires detailed... mehr

     

    Safe and sustainable management of nuclear energy poses major scientific and engineering challenges, one of which is the necessity to make the environmental impacts of the long-term nuclear waste storage as small as possible. This requires detailed understanding and prediction of the behaviour of radionuclides and their migration and retention properties in the geological formations of nuclear waste repositories. The Callovo-Oxfordien rock formation of the French nuclear repository site is mainly composed of clay minerals (illite, smectite and interstratified illite/smectite), quartz, calcite, with some non-negligible amount of organic matter. The adsorption of water can change the properties of mineral surfaces, including protonation state, surface charge, structure, and reactivity [1]. Similarly, the properties of interfacial water are strongly affected by the mineral substrate structure and composition. Recent advances in experimental techniques such as FTIR [2], ellipsometry [3], synchrotron X-ray scattering [4], sum-frequency vibrational spectroscopy [5] are capable of probing the properties of mineral-water interfaces at different levels of hydration. However, the surface-specific results of these experiments are often difficult to quantitatively interpret without having a reliable molecular scale picture of the underlying physical and chemical processes. Molecular computer simulations have become one of the most important tools in the study of such interfacial systems and phenomena by providing invaluable atomistic information on the underlying chemical and physical processes. The present study is aimed at investigating the structural and dynamics effects of three different cations (K+, NH4+, and H3O+) exchanged at the hydrated surface of muscovite mica, which is taken here as a model illite. Molecular dynamics computer simulations were performed using the CLAYFF force field [6] to investigate the important differences of the H-bonding configurations formed by the sorbed species, including H2O, H3O+, and NH4+, in contrast to the behavior of spherical metal ions, such as K+. At the muscovite (001) surface, H2O can donate 2 H-bonds (to other H2O and/or to the surface O atoms) and accept 2 H-bonds (from other H2O), but it can also partially replace surface K+, because the hydrogens of H2O bear some positive charge. This behavior was observed in previous MD simulations of the mica surface [7]. Such surface-adsorbed H2O molecules have their negatively charged oxygen atoms exposed to the fluid phase and accessible for either H-bond acceptance from other H2Os or hydration of metal cations in outer-sphere coordination. For surface H3O+, the charges on the hydrogens are slightly higher than those of H2O, but the oxygen atom of hydronium is now almost hydrophobic, and cannot participate in a H-bond network (e.g., [8]). In contrast, NH4+ can equally well donate H-bonds to the surface O atoms and to the neighboring H2O molecules, but it cannot participate in the hydration shell of a displaced metal cation. Thus, three similar species (H2O - two HB donors and 2 HB acceptors; H3O+ - 3 HB donors and no acceptors; NH4+ - 4 HB donors, no acceptors) can provide for three greatly different structural, energetic, and dynamical situations at the muscovite-water interface. Since the hydrogen-bonding network in any aqueous media provides a natural mechanism of forming low-barrier reaction paths for proton transfer in such systems, it is also an important phenomenon controlling the surface reactivity under various pH conditions. In addition, a detailed study of the structural characteristics of surface-adsorbed NH4+ provides a way for better understanding of the mechanisms of adsorption for organic molecules having amino-groups in their structure, which is quite common for natural organic matter (e.g., [9]). Each of the three systems was simulated at 7 different hydration states providing information on the structure and dynamics of the adsorbed water film in a wide range of relative humidity conditions. The atomic density profiles of water show significant layering at all hydration levels and the layering strongly depends upon the nature of the ionic species present on the surface. Our studies support the fact that the H3O+ ion is less strongly bound when compared to K+ on the muscovite surface as observed in earlier studies [7]. At muscovite surfaces, both NH4+ and H3O+ cations establish strong hydrogen bonds with the surface bridging oxygen atoms and also with the neighbouring H2O molecules at all hydration levels. However, we observed that the interactions are different for both species at low hydration levels (<< molecular monolayer). At low hydration levels, H3O+ prefers to strongly bind as 3-cordinated species to the surface than with the neighbouring waters molecules. However, as the hydration levels increase, H3O+ binds as 2-cordinated species with the surface as is indicated by hydrogen bonding analysis (Figure 1). In contrast, irrespective of the hydration levels, NH4+ ion strongly interacts with the surface as 3-cordinated species because of its tetrahedral geometry. At the same time, we observe from hydrogen bond analysis that the hydrogen bonding network of water has been strongly influenced by the nature of the surface cations present at the mineral-water interface. The dynamics of water molecules were examined by self-diffusion coefficients from the mean square displacement of water oxygen. The diffusion mechanism is similar for K+ and NH4+ but was different for H3O+, in particular at the low hydration states. Furthermore, the spatial and orientation distributions of H2O and ions at the muscovite-water surface are analyzed in quantitative detail. All the simulation results are compared with available experimental data and the results of previous molecular simulations to provide reliable molecular view of the ions and water at the muscovite surface. References [1] Henderson, M. A. Surf. Sci. Rep. 2002, 46, 5-308. [2] Cantrell and G. E. Ewing. J. Phys. Chem. B, 2001, 105, 5434-5439. [3] Beaglehole, D and Christenson, H. K. J. Phys. Chem, 1992, 96, 3395-3403. [4] Fenter, P. and Sturchio, N. C. Progress in Surface Science, 2004, 77, 171-258. [5] Shen, Y. R. and Ostroverkhov, V. Chem. Rev., 2006, 106, 1140-1154. [6] Cygan, R.T., Liang, J.J., and Kalinichev, A.G. J. Phys. Chem. B, 2004, 108, 1255-1266. [7] Wang, J., Kalinichev, A., Kirkpatrick, R., Cygan, R. J. Phys. Chem B., 2005, 109, 15893-15905. [8] Petersen, P.B. and Saykally, R.J. J. Phys. Chem. B, 2005, 109, 7976-7980. [9] Leenheer, J.A. Annals of Environmental Science, 2009, 3, 1-130.

     
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    Übergeordneter Titel: 5th International meeting "Clays in Natural and Engineered Barriers for Radioactive Waste Confinement" ; http://hal.in2p3.fr/in2p3-00769153 ; 5th International meeting "Clays in Natural and Engineered Barriers for Radioactive Waste Confinement", Oct 2012, Montpellier, France
    Schlagworte: [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry; [CHIM.MATE]Chemical Sciences/Material chemistry; [SDE.IE]Environmental Sciences/Environmental Engineering; [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry; [SDE.MCG]Environmental Sciences/Global Changes; [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
  24. Ethylene glycol intercalation in smectites. Molecular dynamics simulation studies
    Autor*in: Szczerba, Marek; Klapyta, Zenon; Kalinichev, Andrey G.
    Erschienen: 2012
    Verlag:  HAL CCSD

    Intercalation of ethylene glycol in smectites (glycolation) is widely used to discriminate smectites and vermiculites from other clays and among themselves. During this process, ethylene glycol molecules enter into the interlayer spaces of the... mehr

     

    Intercalation of ethylene glycol in smectites (glycolation) is widely used to discriminate smectites and vermiculites from other clays and among themselves. During this process, ethylene glycol molecules enter into the interlayer spaces of the swelling clays, leading to the formation of two-layer structure (~17 Å) in the case of smectites, or one-layer structure (~14 Å) in the case of vermiculites. In spite of the relatively broad literature on the understanding/characterization of ethylene glycol/water-clays complexes, the simplified structure of this complex presented by Reynolds (1965) is still used in the contemporary X-ray diffraction computer programs, which simulate structures of smectite and illite-smectite. The monolayer structure is only approximated using the assumption of the interlayer cation and ethylene glycol molecules lying in the middle of interlayer spaces. This study was therefore undertaken to investigate the structure of ethylene glycol/water-clays complex in more detail using molecular dynamics simulation. The structural models of smectites were built on the basis of pyrophyllite crystal structure (Lee and Guggenheim, 1981), with substitution of particular atoms. In most of simulations, the structural model assumed the following composition, considered as the most common in the mixed layer illite-smectites (Środoń et al. 2009): EXCH0.4(Si3.96Al0.04)(Al1.46Fe0.17Mg0.37)O10(OH)2 Atoms of the smectites were described with CLAYFF force field (Cygan et al., 2004), while atoms of water and ethylene glycol with flexible SPC (Berendsen et al., 1981) and OPLS (Jorgensen et al., 1996) force fields, respectively. Ewald summation was used to calculate long range Coulombic interactions and the cutoff was set at 8.5 Å. Results of the simulations show that in the two-layer glycolate the content of water is relatively small: up to 0.8 H2O per half of the smectite unit cell (thereafter phuc). Clear thermodynamic preference of mono- or two-layer structure of the complex is observed for typical smectite. Based on the calculated radial distribution functions, it was confirmed that water and ethylene glycol molecules compete for the coordination sites of the calcium ions in the clay interlayers. It was also found that the differences in the smectite layer charge, charge location, and the type of the interlayer cation affect the ethylene glycol and water packing in the interlayer space and as result have strong influence on the basal spacing and on the structure of complex. Varying amounts and ratio of both ethylene glycol and water are, however, the most important factor influencing the extent of the smectite expansion. Comparison of two-layer structure obtained from molecular dynamics simulations with previous models leads to the conclusion that the arrangement of ethylene glycol molecules in the interlayers, used in simulations of X-ray diffractograms of clays, should be modified. In contrast to the Reynolds (1965) model, the main difference is that, for different location of the clay charge, interlayer ions tend to change their positions. In the case of montmorillonite, calcium ions are located in the middle of the interlayer space, while for beidellite they are located much closer to the clay surface. Water in these structures does not form distinct layers but is distributed rather broadly with a tendency to be concentrated close to the smectite surface. One-layer structure of ethylene glycol/water-smectite complex, characteristic of vermiculite was also proposed. References Berendsen, H.J.C., Postma, J.P.M., van Gunsteren, W.F., Hermans, J. (1981) Interaction models for water in relation to protein hydration. In Intermolecular Forces; Pullman, B., Ed.; D. Reidel: Amsterdam, pp 331. Cygan, R. T., Liang, J. J., and Kalinichev, A. G. (2004) Molecular models of hydroxide, oxyhydroxide, and clay phases and the development of a general force field. Journal of Physical Chemistry B, 108, 1255-1266. Jorgensen,W.L., Maxwell, D.S., Tirado-Rives, J. (1996) Development and testing of the OPLS all-atom force field on conformational energetics and properties of organic liquids. J. Am. Chem. Soc., 118, 11225-11236. Lee J.H., Guggenheim S. (1981) Single crystal X-ray refinement of pyrophyllite-1Tc. American Mineralogist, 66, 350-357 Reynolds R. C. (1965) An X-ray study of an ethylene glycol-montmorillonite complex. American Mineralogist, 50, 990-1001 Środoń J., Zeelmaekers E., Derkowski A. (2009) The charge of component layers of illite-smectite in bentonites and the nature of end-member illite. Clays and Clay Minerals, 57, 650-672

     
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    Übergeordneter Titel: 5th International meeting "Clays in Natural and Engineered Barriers for Radioactive Waste Confinement" ; http://hal.in2p3.fr/in2p3-00769154 ; 5th International meeting "Clays in Natural and Engineered Barriers for Radioactive Waste Confinement", Dec 2012, Montpellier, France
    Schlagworte: [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry; [CHIM.MATE]Chemical Sciences/Material chemistry; [SDE.IE]Environmental Sciences/Environmental Engineering; [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry; [SDE.MCG]Environmental Sciences/Global Changes; [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
  25. Molecular Modeling of the Swelling Properties and Interlayer Structure of Cs, and K-Montmorillonites: Effects of Charge Distribution in the Clay Layers
    Autor*in: Ngouana Wakou, Brice,; Kalinichev, Andrey G.
    Erschienen: 2012
    Verlag:  HAL CCSD

    Reliable prediction of the behaviour of radionuclides and their transport and retention in clayey formations at nuclear waste repositories requires detailed molecular scale understanding of these complex multicomponent systems. As the first step in... mehr

     

    Reliable prediction of the behaviour of radionuclides and their transport and retention in clayey formations at nuclear waste repositories requires detailed molecular scale understanding of these complex multicomponent systems. As the first step in our study of the effects of organic molecules on the adsorption and transport of radionuclides in hydrated clay systems we have investigated the effects of the ordering in charge distributions on the swelling behavior of montmorillonite (a smectite clay). Montmorillonite layered structure consists of aluminum-oxygen octahedral sheet sandwiched between two opposing silicon-oxygen tetrahedral sheets giving rise to a 2:1 clay mineral. Isomorphic substitutions in the tetrahedral and octahedral sheets are responsible of the negative layer charge of montmorillonite clay minerals having the chemical composition (Si8-xXx)(Al4-yYy)O20(OH)4 where X = Al3+, Y = Mg2+, Fe2+.[1]. The montmorillonite models for our study are based on a pyrophillite unit cell structure (5.16Å×8.966Å×9.347Å) obtained from the crystallographic data of Lee et al. [2]. The 4×4×2 simulation supercells were built and substitutions were made in the pyrophillite structure in order to approximate as close as possible the chemical composition of Wyoming montmorillonite [1] M24(Si248Al8)(Al112Mg16)O640(OH)128, where M is either Cs+, or K+. We have explored three different models of the substitution distributions. In the first model, the substitutions were uniformly and orderly distributed within the tetrahedral and octahedral sheets. In the second model, the substituted positions were kept ordered in the octahedral sheets but made disordered in the tetrahedral one. In the third model, the substituted positions of the octahedral sites were additionally made disordered. In order to study the swelling behavior of these montmorillonites, NPT-ensemble molecular dynamics (MD) simulations were run at T = 298 K and P = 1 bar for each of the three different substitution models and with 23 different hydration states ranging from 0 to 700 mgwater/gclay (from 0 to 42 H2O molecules per one monovalent cation). All MD runs were performed for a total of 2 ns using the CLAYFF force field [3]. After the system reached equilibrium, the last 1ns of each MD trajectory was used to compute the clay basal spacing and the swelling thermodynamic properties: hydration energy, immersion energy, isosteric heat of adsorption. These calculations indicate that in addition to the commonly observed 1-layer and 2-layer hydrates, stable hydration states corresponding to 3-layer and 4-layer hydrates can also be distinguished. These stable states (minima of hydration and immersion energies) were then selected to run further 500 ps NVT-ensemble MD simulations at the same temperature. The equilibrium parts of these NVT-simulated trajectories were then used to calculate radial distribution functions and atomic density profiles of the interlayer species in hydrated montmorillonites. References [1] Tsipursky, S.I., Drits, V.A. Clay Minerals, 19, 177-193 (1984). [2] Lee, J.H. and Guggenheim, S. American Mineralogist, 66, 350-357 (1981). [3] Cygan, R.T., Liang, J.J., Kalinichev, A.G. Journal of Physical Chemistry B, 108, 1255-1266 (2004).

     
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    Übergeordneter Titel: XIIIe journées nationale de radiochimie et de chimie nucléaire ; http://hal.in2p3.fr/in2p3-00769157 ; XIIIe journées nationale de radiochimie et de chimie nucléaire, Oct 2012, Nantes, France
    Schlagworte: [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry; [CHIM.MATE]Chemical Sciences/Material chemistry; [SDE.IE]Environmental Sciences/Environmental Engineering; [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry; [SDE.MCG]Environmental Sciences/Global Changes; [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy