Mon·Oct 24, 2016Monday·October 24, 2016

1. 01*

   Status and Future of Nuclear Matrix Elements for Neutrinoless Double-Beta Decay: A Review

   Jonathan Engel🇺🇸 · Javier Menéndez🇯🇵

   The nuclear matrix elements that govern the rate of neutrinoless double beta decay must be accurately calculated if experiments are to reach their full potential. Theorists have been working on the problem for a long time but have recently stepped up their efforts as ton-scale experiments have begun to look feasible. Here we review past and recent work on the matrix elements in a wide variety of nuclear models and discuss work that will be done in the near future. Ab initio nuclear-structure theory, which is developing rapidly, holds out hope of more accurate matrix elements with quantifiable error bars.

   ↳ nucl-thhep-exhep-phnucl-exRept.Prog.Phys.(2017)·645 citations
2. 02*

   Partonic structure of neutral pseudoscalars via two photon transition form factors

   Khepani Raya🇲🇽 · Minghui Ding🇨🇳 · Adnan Bashir🇲🇽 · Lei Chang🇨🇳 · Craig D. Roberts🇺🇸

   The $\gamma {\gamma }^{\ast }\to {\eta }_{c,b}$ transition form factors are computed using a continuum approach to the two valence-body bound-state problem in relativistic quantum field theory, and thereby unified with equivalent calculations of electromagnetic pion elastic and transition form factors. The resulting $\gamma {\gamma }^{\ast }\to {\eta }_c$ form factor, $G_{{\eta }_c}(Q^2)$, is consistent with available data: significantly, at accessible momentum transfers, $Q^2{G}_{{\eta }_c}(Q^2)$ lies well below its conformal limit. These observations confirm that the leading-twist parton distribution amplitudes (PDAs) of heavy-heavy bound-states are compressed relative to the conformal limit. A clear understanding of the distribution of valence-quarks within mesons thus emerges; a picture which connects Goldstone modes, built from the lightest-quarks in Nature, with systems containing the heaviest valence-quarks that can now be studied experimentally, and highlights basic facts about manifestations of mass within the Standard Model.

   ↳ nucl-thhep-exhep-lathep-ph+1PRD(2017)·68 citations
3. 03*

   Production of exotic charmonium in $\gamma \gamma$ interactions at hadronic colliders

   B. D. Moreira🇧🇷 · C. A. Bertulani🇺🇸 · V. P. Goncalves🇧🇷 · F. S. Navarra🇧🇷

   In this paper we investigate the Exotic Charmonium (EC) production in $\gamma \gamma$ interactions present in proton-proton, proton-nucleus and nucleus-nucleus collisions at the CERN Large Hadron Collider (LHC) energies as well as for the proposed energies of the Future Circular Collider (FCC). Our results demonstrate that the experimental study of these processes is feasible and can be used to constrain the theoretical decay widths and shed some light on the configuration of the considered multiquark states.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2016)·31 citations
4. 04*

   Measurement of the cross section and longitudinal double-spin asymmetry for di-jet production in polarized $pp$ collisions at $\sqrt{s}$ = 200 GeV

   STAR Collaboration: L. Adamczyk · J. K. Adkins · G. Agakishiev · M. M. Aggarwal · Z. Ahammed · N. N. Ajitanand · I. Alekseev · D. M. Anderson · R. Aoyama · A. Aparin · D. Arkhipkin · E. C. Aschenauer and 337 other authors

   We report the first measurement of the longitudinal double-spin asymmetry $A_{LL}$ for mid-rapidity di-jet production in polarized $pp$ collisions at a center-of-mass energy of $\sqrt{s}=200$ GeV. The di-jet cross section was measured and is shown to be consistent with next-to-leading order (NLO) perturbative QCD predictions. $A_{LL}$ results are presented for two distinct topologies, defined by the jet pseudorapidities, and are compared to predictions from several recent NLO global analyses. The measured asymmetries, the first such correlation measurements, support those analyses that find positive gluon polarization at the level of roughly 0.2 over the region of Bjorken-$x>0.05$.

   ↳ hep-exnucl-exPRD(2017)·63 citations
5. 05*

   KATANA - a charge-sensitive triggering system for the S$\pi$RIT experiment

   P. Lasko🇵🇱 · M. Adamczyk🇵🇱 · J. Brzychczyk🇵🇱 · P. Hirnyk · J. Łukasik🇵🇱 · P. Pawłowski🇵🇱 · K. Pelczar🇵🇱 · A. Snoch · A. Sochocka · Z. Sosin🇵🇱 · J. Barney🇺🇸 · G. Cerizza and 10 other authors

   KATANA - the Krakow Array for Triggering with Amplitude discrimiNAtion - has been built and used as a trigger and veto detector for the S$\pi$RIT TPC at RIKEN. Its construction allows operating in magnetic field and providing fast response for ionizing particles, giving the approximate forward multiplicity and charge information. Depending on this information, trigger and veto signals are generated. The article presents performance of the detector and details of its construction. A simple phenomenological parametrization of the number of emitted scintillation photons in plastic scintillator is proposed. The effect of the light output deterioration in the plastic scintillator due to the in-beam irradiation is discussed.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2017)·17 citations
6. 06*

   Summary of recent experimental results on strangeness production

   Alexander Kalweit🇨🇭

   This article summarises the highlights of the recent experimental findings on strangeness production presented at the 16th edition of the {\it International Conference on Strangeness in Quark Matter} in Berkeley. Results obtained by eight large experimental collaborations (ALICE, ATLAS, CMS, HADES, LHCb, NA-61, PHENIX, STAR) spanning a large range in centre-of-mass energy and a variety of collision systems were presented at the conference. The article does not aim at being a complete review, but rather at connecting the experimental highlights of the different collaborations and at pointing towards questions which should be addressed by these experiments in future.

   ↳ hep-exhep-phnucl-exJ.Phys.Conf.Ser.(2017)·3 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.