Tue·Jun 4, 2019Tuesday·June 4, 2019

1. 01*

   Flavor hierarchy of jet quenching in relativistic heavy-ion collisions

   Wen-Jing Xing🇨🇳 · Shanshan Cao🇺🇸 · Guang-You Qin🇨🇳 · Hongxi Xing

   Relativistic heavy-ion experiments have observed similar quenching effects for (prompt) $D$ mesons compared to charged hadrons for transverse momenta larger than 6-8~GeV, which remains a mystery since heavy quarks typically lose less energies in quark-gluon plasma than light quarks and gluons. Recent measurements of the nuclear modification factors of $B$ mesons and $B$-decayed $D$ mesons by the CMS Collaboration provide a unique opportunity to study the flavor hierarchy of jet quenching. Using a linear Boltzmann transport model combined with hydrodynamics simulation, we study the energy loss and nuclear modification for heavy and light flavor jets in high-energy nuclear collisions. By consistently taking into account both quark and gluon contributions to light and heavy flavor hadron productions within a next-to-leading order perturbative QCD framework, we obtain, for the first time, a satisfactory description of the experimental data on the nuclear modification factors for charged hadrons, $D$ mesons, $B$ mesons and $B$-decayed $D$ mesons simultaneously over a wide range of transverse momenta (8-300~GeV). This presents a solid solution to the flavor puzzle of jet quenching and constitutes a significant step towards the precision study of jet-medium interaction. Our study predicts that at transverse momenta larger than 30-40~GeV, $B$ mesons also exhibit similar suppression effects to charged hadrons and $D$ mesons, which may be tested by future measurements.

   ↳ hep-phnucl-exnucl-thPLB(2020)·62 citations
2. 02*

   The possibility of ${}^{14}$C cluster as a building block of medium mass nuclei

   N. Itagaki🇯🇵 · A. V. Afanasjev🇺🇸 · D. Ray

   The possibility of the ${}^{14}$C cluster being a basic building block of medium mass nuclei is discussed. Although $\alpha$ cluster structures have been widely discussed in the light $N\approx Z$ mass region, the neutron to proton ratio deviates from unity in the nuclei near $\beta$-stability line and in neutron-rich nuclei. Thus, more neutron-rich objects with $N>Z$ could become the building blocks of cluster structures in such nuclei. The ${}^{14}$C nucleus is strongly bound and can be regarded as such a candidate. In addition, the path to the lowest shell-model configuration at short relative distances is closed for the ${}^{14}$C+${}^{14}$C structure contrary to the case of the ${}^{12}$C+${}^{12}$C structure; this allows to keep appreciable separation distance between the ${}^{14}$C clusters. The recent development of antisymmetrized quasi-cluster model (AQCM) allows us to utilize $jj$-coupling shell model wave function for each cluster in a simplified way. The AQCM results for the ${}^{14}$C+${}^{14}$C structure in ${}^{28}$Mg are compared with the ones of cranked relativistic mean field (CRMF) calculations. Although theoretical frameworks of these two models are quite different, they give similar results for the nucleonic densities and rotational properties of the structure under investigation. The existence of linear chain three ${}^{14}$C cluster structure in ${}^{42}$Ar has also been predicted in AQCM. These results confirm the role of the ${}^{14}$C cluster as a possible building block of cluster structures in medium mass nuclei.

   ↳ nucl-thnucl-exPRC(2020)·18 citations
3. 03*

   Shell model results for ${}^{47-58}$Ca isotopes in the $fp$, $fp{g}_{9/2}$ and $fp{g}_{9/2}{d}_{5/2}$ model spaces

   Bharti Bhoy🇮🇳 · Praveen C. Srivastava🇮🇳 · Kazunari Kaneko🇯🇵

   We have reported shell-model results for ${}^{47-58}$Ca isotopes in the $fp$, $fp{g}_{9/2}$ and $fp{g}_{9/2}{d}_{5/2}$ model spaces using realistic $NN$ interaction. We have also performed a systematic shell-model study using interactions derived from in-medium similarity-renormalization group (IM-SRG) targeted for a particular nucleus with chiral $NN$ and $3N$ forces. The results obtained are in a reasonable agreement with the available experimental data in $fp$ model space with $NN$ interaction. It is shown that the $g_{9/2}$ and $d_{5/2}$ orbitals play an important role for heavier neutron-rich ${}^{54-58}$Ca isotopes, while it is marginal for ${}^{47-52}$Ca. We have also examined spectroscopic factor strengths using $NN$ and $NN+3N$ interactions for recently available experimental data.

   ↳ nucl-thnucl-exJ.Phys.G(2020)·12 citations
4. 04*

   Mapping the Phases of Quantum Chromodynamics with Beam Energy Scan

   Adam Bzdak🇵🇱 · ShinIchi Esumi🇯🇵 · Volker Koch🇺🇸 · Jinfeng Liao🇺🇸 · Mikhail Stephanov🇺🇸 · Nu Xu🇨🇳

   We review the present status of the search for a phase transition and critical point as well as anomalous transport phenomena in Quantum Chromodynamics (QCD), with an emphasis on the Beam Energy Scan program at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. We present the conceptual framework and discuss the observables deemed most sensitive to a phase transition, QCD critical point, and anomalous transport, focusing on fluctuation and correlation measurements. Selected experimental results for these observables together with those characterizing the global properties of the systems created in heavy ion collisions are presented. We then discuss what can be already learned from the currently available data about the QCD critical point and anomalous transport as well as what additional measurements and theoretical developments are needed in order to discover these phenomena.

   ↳ nucl-thhep-lathep-phnucl-exPhys.Rept.(2020)·616 citations
5. 05*

   Influence of initial-state momentum anisotropy on the final-state collectivity in small collision systems

   Maowu Nie🇨🇳 · Li Yi🇨🇳 · Jiangyong Jia🇺🇸 · Guoliang Ma🇨🇳

   A multi-phase transport model is used to understand the origin of long-range collective azimuthal correlations in small-system collisions. To disentangle between collectivity associated with initial-state intrinsic momentum anisotropy and the collectivity arising as a final-state response to the collision geometry, we studied the development of collectivity in 5.02 TeV $p$+Pb collisions with both initial-state and final-state effects included. We find that the initial momentum anisotropy may not be fully isotropized through parton interactions, and the final-state partonic collectivity in general are correlated with both the initial momentum anisotropy and the shape of the collision geometry. The initial momentum anisotropy also influences the event by event fluctuation of collective flow. Therefore the mere evidence of geometry response of the collective flow can not rule out the presence of large contributions from the initial state.

   ↳ nucl-thhep-phnucl-exPRC(2019)·18 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.