Measurement of the longitudinal spin transfer to Λ and hyperons in polarised muon DIS

• Published in: The European physical journal. C, Particles and fields Particles and fields, 2009-11, Vol.64 (2), p.171-179
• Main Authors: Balestra, F., Barth, J., Baum, G., Bedfer, Y., Bertini, R., Bettinelli, M., Birsa, R., Bradamante, F., Bravar, A., Bressan, A., Brona, G., Bussa, M. P., Chiosso, M., Chung, S. U., Cicuttin, A., Dalla Torre, S., Dafni, T., Denisov, O. Yu, Diaz, V., Dinkelbach, A. M., Donskov, S. V., Doshita, N., Duic, V., Eversheim, P. D., Faessler, M., Finger, M., Fischer, H., Franco, C., Garfagnini, R., Gavrichtchouk, O. P., Giorgi, M., Gobbo, B., Goertz, S., Grajek, O. A., Grube, B., Gushterski, R., Haas, F., von Harrach, D., Hasegawa, T., Heinsius, F. H., Hermann, M., Herrmann, F., Ishimoto, S., Ivanov, O., Iven, B., Ketzer, B., Khokhlov, Yu. A., Klimaszewski, K., Koblitz, S., Koivuniemi, J. H., Kondo, K., Königsmann, K., Konopka, R., Konorov, I., Kouznetsov, O., Kroumchtein, Z. V., Kuhn, R., Lichtenstadt, J., Liska, T., Maggiora, A., Maggiora, M., Magnon, A., Mallot, G. K., Marroncle, J., Martin, A., Maximov, A. N., Michigami, T., Mikhailov, Yu. V., Moinester, M. A., Nagel, T., Negrini, S., Neyret, D., Ostrick, M., Padee, A., Paul, S., Peshekhonov, D. V., Piragino, G., Pochodzalla, J., Pontecorvo, G., Ramos, S., Rocco, E., Rondio, E., Ryabchikov, D. I., Sbrizzai, G., Schiavon, P., Schröder, W., Shevchenko, O. Yu, Sosio, S., Sulc, M., Tessaro, S., Tessarotto, F., Teufel, A., Venugopal, G., Vlassov, N. V., Vossen, A., Wollny, H., Zaremba, K., Zemlyanichkina, E., Zhao, J.
• Format: Article
• Language: English
• Subjects: Astronomy; Astrophysics and Cosmology; CERN; Elementary Particles; Hadrons; Heavy Ions; Hyperons; Inelastic scattering; Letter; Longitude; Magnetic properties; Measurement Science and Instrumentation; Muons; Nuclear Energy; Nuclear Physics; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; String Theory
• ISSN: 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-009-1143-7

The longitudinal polarisation transfer from muons to Λ  and  hyperons, , has been studied in deep-inelastic scattering off an unpolarised isoscalar target at the COMPASS experiment at CERN. The spin transfers to Λ  and  produced in the current fragmentation region exhibit different behaviours as a function of x and x F . The measured x and x F dependences of D LL Λ are compatible with zero, while tends to increase with x F , reaching values of 0.4–0.5. The resulting average values are D LL Λ = −0.012±0.047±0.024 and = 0.249±0.056±0.049. These results are discussed in the frame of recent model calculations.