Nuclear Theory·nucl-th

Thursday·April 7, 2022

3 papers—1 primary·2 cross-listed

01
[Submitted on 5 Apr 2022]
Dynamics of non-Gaussian fluctuations in model A
Thomas Schaefer🇺🇸 · Vladimir Skokov🇺🇸
Motivated by the experimental search for the QCD critical point we perform simulations of a stochastic field theory with purely relaxational dynamics (model A). We verify the expected dynamic scaling of correlation functions. Using a finite size scaling analysis we obtain the dynamic critical exponent $z = 2.026 (56)$ . We investigate time dependent correlation functions of higher moments $M^{n} (t)$ of the order parameter $M (t)$ for $n = 1, 2, 3, 4$ . We obtain dynamic scaling with the same critical exponent $z$ for all $n$ , but the relaxation constant depends on $n$ . We also study the relaxation of $M^{n} (t)$ after a quench, where the simulation is initialized in the high temperature phase, and the dynamics is studied at the critical temperature $T_{c}$ . We find that the evolution does not follow simple scaling with the dynamic exponent $z$ , and that it involves an early time rise followed by late stage relaxation.
Comments:
13 pages, 7 figures. Minor error corrected; shifts normalization of m^2
Subjects:
Nuclear Theory (nucl-th); Statistical Mechanics (cond-mat.stat-mech); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2204.02433 [pdf]
PRD(2022)·26 citations
02
[Submitted on 6 Apr 2022] (cross-list from hep-ph)
An updated review of the new hadron states
Hua-Xing Chen🇨🇳 · Wei Chen🇨🇳 · Xiang Liu🇨🇳 · Yan-Rui Liu🇨🇳 · Shi-Lin Zhu🇨🇳
The past decades witnessed the golden era of hadron physics. Many excited open heavy flavor mesons and baryons have been observed since 2017. We shall provide an updated review of the recent experimental and theoretical progresses in this active field. Besides the conventional heavy hadrons, we shall also review the recently observed open heavy flavor tetraquark states $X (2900)$ and $T_{cc}^{+} (3875)$ as well as the hidden heavy flavor multiquark states $X (6900)$ , $P_{cs} (4459)^{0}$ , $Z_{cs} (3985)^{-}$ , $Z_{cs} (4000)^{+}$ , and $Z_{cs} (4220)^{+}$ . We will also cover the recent progresses on the glueballs and light hybrid mesons, which are the direct manifestations of the non-Abelian $S U (3)$ gauge interaction of the Quantum Chromodynamics in the low-energy region.
Comments:
Review accepted by Reports on Progress in Physics, 179 pages, 87 figures, 15 tables
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2204.02649 [pdf]
Rept.Prog.Phys.(2023)·785 citations
03
[Submitted on 6 Apr 2022] (cross-list from hep-ph)
Lepton pair photoproduction in peripheral relativistic heavy-ion collisions
Ren-jie Wang🇨🇳 · Shuo Lin🇨🇳 · Shi Pu🇨🇳 · Yi-fei Zhang🇨🇳 · Qun Wang🇨🇳
We study the lepton pair photoproduction in peripheral heavy-ion collisions based on the formalism in our previous work [Phys. Rev. D 104, 056011 (2021)]. We present the numerical results for the distributions of the transverse momentum, azimuthal angle and invariant mass for $e^{+} e^{-}$ and $μ^{+} μ^{-}$ pairs as functions of the impact parameter and other kinematic variables in Au+Au collisions. Our calculation incorporates the information on the transverse momentum and polarization of photons which is essential to describe the experimental data. We observe a broadening effect in the transverse momentum for lepton pairs with and without smear effects. We also observe a significant enhancement in the distribution of $cos (2 φ)$ for $μ^{+} μ^{-}$ pairs. Our results provide a baseline for future studies of other higher order corrections beyond Born approximation and medium effects in the lepton pair production.
Comments:
19 pages, 10 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2204.02761 [pdf]
PRD(2022)·29 citations

Affiliations

first authorsco-authorsvia INSPIRE

Dynamics of non-Gaussian fluctuations in model A

An updated review of the new hadron states

Lepton pair photoproduction in peripheral relativistic heavy-ion collisions

Affiliations