Weak effects in proton beam asymmetries at polarised RHIC and beyond

Moretti, S., Nolten, M.R. and Ross, D.A. (2006) Weak effects in proton beam asymmetries at polarised RHIC and beyond. Physics Letters B, 643 (2), 86-92. (doi:10.1016/j.physletb.2006.06.084).

Record type: Article

Abstract

We report on a calculation of the full one-loop weak corrections through the order to parton–parton scattering in all possible channels at the Relativistic Heavy Ion Collider (RHIC) running with polarised pp beams (RHIC-Spin). This study extends the analysis previously carried out for the case of 2?2 subprocesses with two external gluons, by including all possible four-quark modes with and without an external gluon. The additional contributions due to the new four-quarks processes are extremely large, of order 50 to 100% (of either sign), not only in the case of parity-violating beam asymmetries but also for the parity-conserving ones and (although to a more limited extent) the total cross section. Such effects on the CP-violating observables would be an astounding 5 times larger for the case of the LHC with polarised beams—which has been discussed as one of the possible upgrades of the CERN machine—whereas they would be much reduced for the case of the CP-conserving ones as well as the cross section.

This record has no associated files available for download.