Polarization of Λ and Λ¯ in 920 GeV fixed-target proton–nucleus collisions

Autor: I. Abt, M. Adams, M. Agari, H. Albrecht, A. Aleksandrov, V. Amaral, A. Amorim, S.J. Aplin, V. Aushev, Y. Bagaturia, V. Balagura, M. Bargiotti, O. Barsukova, J. Bastos, J. Batista, C. Bauer, Th.S. Bauer, A. Belkov, Ar. Belkov, I. Belotelov, A. Bertin, B. Bobchenko, M. Böcker, A. Bogatyrev, G. Bohm, M. Bräuer, M. Bruinsma, M. Bruschi, P. Buchholz, T. Buran, J. Carvalho, P. Conde, C. Cruse, M. Dam, K.M. Danielsen, M. Danilov, S. De Castro, H. Deppe, X. Dong, H.B. Dreis, V. Egorytchev, K. Ehret, F. Eisele, D. Emeliyanov, S. Erhan, S. Essenov, L. Fabbri, P. Faccioli, M. Feuerstack-Raible, J. Flammer, B. Fominykh, M. Funcke, Ll. Garrido, A. Gellrich, B. Giacobbe, J. Gläß, D. Goloubkov, Y. Golubkov, A. Golutvin, I. Golutvin, I. Gorbounov, A. Gorišek, O. Gouchtchine, D.C. Goulart, S. Gradl, W. Gradl, F. Grimaldi, Yu. Guilitsky, J.D. Hansen, J.M. Hernández, W. Hofmann, M. Hohlmann, T. Hott, W. Hulsbergen, U. Husemann, O. Igonkina, M. Ispiryan, T. Jagla, C. Jiang, H. Kapitza, S. Karabekyan, N. Karpenko, S. Keller, J. Kessler, F. Khasanov, Yu. Kiryushin, I. Kisel, E. Klinkby, K.T. Knöpfle, H. Kolanoski, S. Korpar, C. Krauss, P. Kreuzer, P. Križan, D. Krücker, S. Kupper, T. Kvaratskheliia, A. Lanyov, K. Lau, B. Lewendel, T. Lohse, B. Lomonosov, R. Männer, R. Mankel, S. Masciocchi, I. Massa, I. Matchikhilian, G. Medin, M. Medinnis, M. Mevius, A. Michetti, Yu. Mikhailov, R. Mizuk, R. Muresan, M. zur Nedden, M. Negodaev, M. Nörenberg, S. Nowak, M.T. Núñez Pardo de Vera, M. Ouchrif, F. Ould-Saada, C. Padilla, D. Peralta, R. Pernack, R. Pestotnik, B.AA. Petersen, M. Piccinini, M.A. Pleier, M. Poli, V. Popov, D. Pose, S. Prystupa, V. Pugatch, Y. Pylypchenko, J. Pyrlik, K. Reeves, D. Reßing, H. Rick, I. Riu, P. Robmann, I. Rostovtseva, V. Rybnikov, F. Sánchez, A. Sbrizzi, M. Schmelling, B. Schmidt, A. Schreiner, H. Schröder, U. Schwanke, A.J. Schwartz, A.S. Schwarz, B. Schwenninger, B. Schwingenheuer, F. Sciacca, N. Semprini-Cesari, S. Shuvalov, L. Silva, L. Sözüer, S. Solunin, A. Somov, S. Somov, J. Spengler, R. Spighi, A. Spiridonov, A. Stanovnik, M. Starič, C. Stegmann, H.S. Subramania, M. Symalla, I. Tikhomirov, M. Titov, I. Tsakov, U. Uwer, C. van Eldik, Yu. Vassiliev, M. Villa, A. Vitale, I. Vukotic, H. Wahlberg, A.H. Walenta, M. Walter, J.J. Wang, D. Wegener, U. Werthenbach, H. Wolters, R. Wurth, A. Wurz, Yu. Zaitsev, M. Zavertyaev, T. Zeuner, A. Zhelezov, Z. Zheng, R. Zimmermann, T. Živko, A. Zoccoli
Rok vydání: 2006
Předmět:
Zdroj: Physics Letters B. 638:415-421
ISSN: 0370-2693
Popis: A measurement of the polarization of Λ and Λ ¯ baryons produced in pC and pW collisions at s = 41.6 GeV has been performed with the HERA-B spectrometer. The measurements cover the kinematic range of 0.6 GeV / c p ⊥ 1.2 GeV / c in transverse momentum and − 0.15 x F 0.01 in Feynman-x. The polarization results from the two different targets agree within the statistical error. In the combined data set, the largest deviation from zero, + 0.054 ± 0.029 , is measured for x F ≲ − 0.07 . Zero polarization is expected at x F = 0 in the absence of nuclear effects. The polarization results for the Λ agree with a parametrization of previous measurements which were performed at positive x F values, where the Λ polarization is negative. Results of Λ ¯ polarization measurements are consistent with zero.
Databáze: OpenAIRE