The transverse polarization of Λ and Λ¯ hyperons produced in proton-proton collisions at a center-of-mass energy of 7 TeV is measured. The analysis uses 760μb-1 of minimum bias data collected by the ATLAS detector at the LHC in the year 2010. The measured transverse polarization averaged over Feynman xF from 5×10-5 to 0.01 and transverse momentum pT from 0.8 to 15 GeV is -0.010$\pm$0.005(stat)$\pm$0.004(syst) for Λ and 0.002$\pm$0.006(stat)$\pm$0.004(syst) for Λ¯. It is also measured as a function of xF and pT, but no significant dependence on these variables is observed. Prior to this measurement, the polarization was measured at fixed-target experiments with center-of-mass energies up to about 40 GeV. The ATLAS results are compatible with the extrapolation of a fit from previous measurements to the xF range covered by this measurement. \copyright 2015 CERN, for the ATLAS Collaboration.
Measurement of the transverse polarization of Λ and Λ ¯ hyperons produced in proton-proton collisions at s =7TeV using the ATLAS detector / Aad, G., Aloisio, A., Alviggi, M., Canale, V., Chiefari, G., DELLA PIETRA, M., DELLA VOLPE, D., Merola, L., Patricelli, S., Conventi, F., Rossi, E., Perrella, S., SANCHEZ PINEDA, A.R., Carlino, G., DE ASMUNDIS, R., DI DONATO, C., Doria, A., Iengo, P., Izzo, V., Sekhniaidze, G., et al.. - In: PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY. - ISSN 1550-7998. - 91:3(2015). [10.1103/PhysRevD.91.032004]
Measurement of the transverse polarization of Λ and Λ ¯ hyperons produced in proton-proton collisions at s =7TeV using the ATLAS detector
ALOISIO, ALBERTO;ALVIGGI, MARIAGRAZIA;CANALE, VINCENZO;CHIEFARI, GIOVANNI;DELLA PIETRA, MASSIMO;DELLA VOLPE, DOMENICO;MEROLA, LEONARDO;PATRICELLI, SERGIO;CONVENTI, FRANCESCO;ROSSI, ELVIRA;PERRELLA, SABRINA;SANCHEZ PINEDA, ARTURO RODOLFO;CARLINO, GIANPAOLO;DE ASMUNDIS, Riccardo;DI DONATO, CAMILLA;IENGO, PAOLO;IZZO, VINCENZO;GIORDANO, RAFFAELE;
2015
Abstract
The transverse polarization of Λ and Λ¯ hyperons produced in proton-proton collisions at a center-of-mass energy of 7 TeV is measured. The analysis uses 760μb-1 of minimum bias data collected by the ATLAS detector at the LHC in the year 2010. The measured transverse polarization averaged over Feynman xF from 5×10-5 to 0.01 and transverse momentum pT from 0.8 to 15 GeV is -0.010$\pm$0.005(stat)$\pm$0.004(syst) for Λ and 0.002$\pm$0.006(stat)$\pm$0.004(syst) for Λ¯. It is also measured as a function of xF and pT, but no significant dependence on these variables is observed. Prior to this measurement, the polarization was measured at fixed-target experiments with center-of-mass energies up to about 40 GeV. The ATLAS results are compatible with the extrapolation of a fit from previous measurements to the xF range covered by this measurement. \copyright 2015 CERN, for the ATLAS Collaboration.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
