Measurement of the transverse polarization of Λ and Λ¯ hyperons produced in proton-proton collisions at √s=7 TeV using the ATLAS detector

Allison, Lee and Barton, Adam and Beattie, Michael and Borissov, Guennadi and Bouhova-Thacker, Eva and Chilingarov, Alexandre and Dearnaley, William and Fox, Harald and Grimm, Kathryn and Henderson, Robert and Hughes, Gareth and Jones, Roger William Lewis and Kartvelishvili, Vakhtang and Long, Robin and Love, Peter and Maddocks, Harvey and Smizanska, Maria and Walder, James (2015) Measurement of the transverse polarization of Λ and Λ¯ hyperons produced in proton-proton collisions at √s=7  TeV using the ATLAS detector. Physical Review D, 91. ISSN 1550-7998

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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 760  μb−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±0.005(stat)±0.004(syst) for Λ and 0.002±0.006(stat)±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.

Item Type:
Journal Article
Journal or Publication Title:
Physical Review D
Additional Information:
© 2015 CERN, for the ATLAS Collaboration
ID Code:
74034
Deposited By:
Deposited On:
18 Jun 2015 05:59
Refereed?:
Yes
Published?:
Published
Last Modified:
27 May 2020 03:56