Thu·Oct 5, 2017Thursday·October 5, 2017

1. 01*

   Berry phases in an electric-dipole-moment experiment in an all-electric storage ring

   Alexander J. Silenko🇷🇺

   Systematic effects caused by the Berry (geometric) phases in an electric-dipole-moment experiment in an all-electric storage ring are considered. We analyze the experimental setup when the spin is frozen and local longitudinal and vertical electric fields alternate. Due to the Berry phases, the spin rotates about the radial axis. The corresponding systematic error is rather important while it can be canceled with clockwise and counterclockwise beams. The Berry phases also lead to the spin rotation about the radial axis. This effect can be canceled with clockwise and counterclockwise beams as well. The sign of the azimuthal component of the angular velocity of the spin precession depends on the starting point where the spin orientation is perfect. The radial component of this quantity keeps its value and sign for each starting point. When the longitudinal and vertical electric fields are joined in the same sections without any alternation, the systematic error due to the geometric phases does not appear. However, another systematic effect of the spin rotation about the azimuthal axis takes place and has opposite signs for clockwise and counterclockwise beams.

   nucl-exhep-exhep-thphysics.acc-phNonlin.Phenom.Complex Syst.(2017)·1 citation
2. 02*

   Investigating the Transverse Single Spin Asymmetry in the Inelastic $J/\Psi$ photoproduction in $p^{\uparrow }p$ and $p^{\uparrow }A$ collisions

   V. P. Goncalves🇧🇷

   In this paper we propose to investigate the transverse single spin asymmetry in the inelastic $J/\Psi$ photoproduction in $p^{\uparrow }p$ and $p^{\uparrow }A$ collisions at RHIC energies. At leading order this process probes the gluon Sivers function. We predict large values for the cross sections, which indicates that its experimental analysis is, in principle, feasible. The rapidity dependence of the single spin asymmetry is presented. We obtain that the asymmetry is strongly dependent on the model used for the gluon Sivers function and that it can be probed by the analysis of the $J/\Psi$ production at forward rapidities. Our results indicate that a future experimental analysis of this process can be useful to constrain the gluon Sivers function.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2018)·7 citations
3. 03*

   Pinning down the linearly-polarised gluons inside unpolarised protons using quarkonium-pair production at the LHC

   Jean-Philippe Lansberg🇫🇷 · Cristian Pisano🇮🇹 · Florent Scarpa🇫🇷 · Marc Schlegel🇩🇪

   We show that the production of J/psi or Upsilon pairs in unpolarised pp collisions is currently the best process to measure the momentum-distribution of linearly-polarised gluons inside unpolarised protons through the study of azimuthal asymmetries. Not only the short-distance coefficients for such reactions induce the largest possible cos 4 phi modulations, but analysed data are already available. Among the various final states previously studied in unpolarised pp collisions within the TMD factorisation approach, di-J/psi production exhibits by far the largest asymmetries, up to 50% in the region studied by the ATLAS and CMS experiments. In addition, we use the very recent LHCb data at 13 TeV to perform the first fit of the unpolarised transverse-momentum-dependent gluon distribution.

   ↳ hep-phhep-exnucl-exnucl-thPLB(2018)·94 citations
4. 04*

   A New Correlator to Detect and Characterize the Chiral Magnetic Effect

   Niseem Magdy (1) · Shuzhe Shi (2) · Jinfeng Liao (2) · N. Ajitanand (1) · Roy A. Lacey (1) ((1) Department of Chemistry, State University of New York, Stony Brook, New York, (2) Physics Department and Center for Exploration of Energy and Matter, Indiana University, IN)

   A charge-sensitive in-event correlator is proposed and tested for its efficacy to detect and characterize charge separation associated with the Chiral Magnetic Effect (CME) in heavy ion collisions. Tests, performed with the aid of two reaction models, indicate discernible responses for background- and CME-driven charge separation, relative to the second- (${\Psi }_2$) and third-order (${\Psi }_3$) event planes, which could serve to identify the CME. The tests also indicate a degree of sensitivity which would enable robust characterization of the CME via Anomalous Viscous Fluid Dynamics (AVFD) model comparisons.

   ↳ physics.data-annucl-exnucl-thPRC(2018)·72 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.