Wed·Jan 13, 2016Wednesday·January 13, 2016

1. 01*

   Independent measurement of the Hoyle state $\beta$ feeding from 12B using Gammasphere

   M. Munch🇩🇰 · M. Alcorta🇨🇦 · H. O. U. Fynbo🇩🇰 · M. Albers🇺🇸 · S. Almaraz-Calderon🇺🇸 · M. L. Avila · A. D. Ayangeakaa🇺🇸 · B. B. Back🇺🇸 · P. F. Bertone🇺🇸 · P. F. F. Carnelli · M. P. Carpenter🇺🇸 · C. J. Chiara🇺🇸 and 19 other authors

   Using an array of high-purity Compton-suppressed germanium detectors, we performed an independent measurement of the $\beta$-decay branching ratio from ${}^{12}\mathrm{B}$ to the second-excited (Hoyle) state in ${}^{12}\mathrm{C}$. Our result is $0.64(11)\%$, which is a factor $\sim 2$ smaller than the previously established literature value, but is in agreement with another recent measurement. This could indicate that the Hoyle state is more clustered than previously believed. The angular correlation of the Hoyle state $\gamma$ cascade has also been measured for the first time. It is consistent with theoretical predictions.

   nucl-exPRC(2016)·9 citations
2. 02*

   Electromagnetic Radiation from QCD Matter: Theory Overview

   Chun Shen (McGill U.)🇨🇦

   Recent theory developments in electromagnetic radiation from relativistic heavy-ion collisions are reviewed. Electromagnetic observables can serve as a thermometer, a viscometer, and tomographic probes to the collision system. The current status of the "direct photon flow puzzle" is highlighted.

   ↳ nucl-thhep-phnucl-exNPA(2016)·42 citations
3. 03*

   Jets in d(p)-A Collisions: Color Transparency or Energy Conservation

   Michael Kordell II🇺🇸 · Abhijit Majumder🇺🇸

   The production of jets, and high momentum hadrons from jets, produced in deuteron ($d$)-$Au$ collisions at the relativistic heavy-ion collider (RHIC) and proton ($p$)-$Pb$ collisions at the large hadron collider (LHC) are studied as a function of centrality, a measure of the impact parameter of the collision. A modified version of the event generator PYTHIA, widely used to simulate $p$-$p$ collisions, is used in conjunction with a nuclear Monte-Carlo event generator which simulates the locations of the nucleons within a large nucleus. We demonstrate how events with a hard jet may be simulated, in such a way that the parton distribution function of the projectile is frozen during its interaction with the extended nucleus. Using our approach, we demonstrate that the puzzling enhancement seen in peripheral events at RHIC and the LHC, as well as the suppression seen in central events at the LHC are mainly due to mis-binning of central and semi-central events, containing a jet, as peripheral events. This occurs due to the suppression of soft particle production away from the jet, caused by the depletion of energy available in a nucleon of the deuteron (in $d$-$Au$ at RHIC) or in the proton (in $p$-$Pb$ at LHC), after the production of a hard jet. We conclude that partonic correlations built out of simple energy conservation are mostly responsible for such an effect.

   ↳ nucl-thhep-phnucl-exPRC(2018)·37 citations
4. 04*

   Hidden-charm Pentaquark States in Heavy Ion Collisions at the Large Hadron Collider

   Rui-Qin Wang🇨🇳 · Jun Song🇨🇳 · Kai-Jia Sun🇨🇳 · Lie-Wen Chen🇨🇳 · Gang Li🇨🇳 · Feng-Lan Shao🇨🇳

   In the framework of the quark combination, we derive the yield formulas and study the yield ratios of the hidden-charm pentaquark states in ultra-relativistic heavy ion collisions. We propose some interesting yield ratios which clearly exhibit the production relationships between different hidden-charm pentaquark states. We show how to employ a specific quark combination model to evaluate the yields of exotic $P_c^{+}(4380)$, $P_c^{+}(4450)$ and their partners on the basis of reproducing the yields of normal identified hadrons, and execute the calculations in central Pb+Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV as an example.

   ↳ hep-phnucl-exnucl-thPRC(2016)·19 citations
5. 05*

   Nuclear collisions at the Future Circular Collider

   N. Armesto🇪🇸 · A. Dainese🇮🇹 · D. d'Enterria🇨🇭 · S. Masciocchi🇩🇪 · C. Roland🇺🇸 · C.A. Salgado🇪🇸 · M. van Leeuwen🇳🇱 · U.A. Wiedemann🇨🇭

   The Future Circular Collider is a new proposed collider at CERN with centre-of-mass energies around 100 TeV in the pp mode. Ongoing studies aim at assessing its physics potential and technical feasibility. Here we focus on updates in physics opportunities accessible in pA and AA collisions not covered in previous Quark Matter contributions, including Quark-Gluon Plasma and gluon saturation studies, novel hard probes of QCD matter, and photon-induced collisions.

   ↳ hep-phhep-exnucl-exnucl-thNPA(2016)·10 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.