Nuclear Theory·nucl-th

Monday·November 25, 2024

11 papers—4 primary·7 cross-listed

05
Constraining Jet Quenching in Heavy-Ion Collisions with Bayesian Inference
Alexandre Falcão🇳🇴 · Konrad Tywoniuk🇳🇴
Jet suppression and modification is a hallmark feature of heavy-ion collisions. This can be attributed to an accumulated set of effects, including radiative and elastic energy loss and reabsorption of thermalized energy within the jet cone, which are encoded in a quenching weight, determining the probability distribution for a shift of the $p_{T}$ (energy loss). We perform a data-driven analysis, based on Bayesian inference, to extract information about the energy-loss distribution experienced by propagating jets using generic and flexible parametrizations. We first establish the consistency between different data-sets and, thereby, provide evidence for the universality of the quark/gluon quenching weights for different observables. Furthermore, we extract that the color dependence of energy loss is slightly bigger than what expected from Casimir scaling, pointing to the importance of multi-parton quenching within high- $p_{T}$ jets at the LHC.
↳ hep-phhep-exnucl-thJHEP(2026)·6 citations
06
CompactObject: An open-source Python package for full-scope neutron star equation of state inference
Chun Huang🇺🇸 · Tuhin Malik🇵🇹 · João Cartaxo🇵🇹 · Shashwat Sourav🇺🇸 · Wenli Yuan🇨🇳 · Tianzhe Zhou🇨🇳 · Xuezhi Liu🇨🇳 · John Groger🇺🇸 · Xieyuan Dong🇨🇳 · Nicole Osborn🇺🇸 · Nathan Whitsett🇺🇸 · Zhiheng Wang🇺🇸 and 5 other authors
The CompactObject package is an open-source software framework developed to constrain the neutron star equation of state (EOS) through Bayesian statistical inference. It integrates astrophysical observational constraints from X-ray timing, gravitational wave events, and radio measurements, as well as nuclear experimental constraints derived from perturbative Quantum Chromodynamics (pQCD) and Chiral Effective Field Theory ( $χ$ EFT). The package supports a diverse range of EOS models, including meta-model like and several physics-motivated EOS models. It comprises three independent components: an EOS generator module that currently provides seven EOS choices, a Tolman-Oppenheimer-Volkoff (TOV) equation solver, that allows the determination of the Mass Radius and Tidal deformability as observables, and a comprehensive Bayesian inference workflow module, including a complete pipeline for implementing EOS Bayesian inference. Each component can be used independently in different scientific research contexts, such as nuclear physics and astrophysics. In addition, CompactObject is designed to work in synergy with existing software such as CompOSE, allowing the use of the CompOSE EOS database to extend the EOS options available.
↳ astro-ph.HEastro-ph.IMnucl-th26 citations
07
Lattice gradient flows (de-)stabilizing topological sectors
Yuya Tanizaki🇯🇵 · Akio Tomiya🇯🇵 · Hiromasa Watanabe🇯🇵
We investigate the stability of topological charge under gradient flow taking the admissibility condition into account. For the $S U (2)$ Wilson gauge theory with $β = 2.45$ and $L^{4} = 1 2^{4}$ , we numerically show that the gradient flows with the Iwasaki and DBW2 gauge actions stabilize the topological sectors significantly, and they have qualitatively different behaviors compared with the Wilson and tree-level Symanzik flows. By considering the classical continuum limit of the flow actions, we discuss that the coefficient of dimension- $6$ operators has to be positive for stabilizing the one-instanton configuration, and the Iwasaki and DBW2 actions satisfy this criterion while the Wilson and Symanzik actions do not. Moreover, we observe that the DBW2 flow stabilizes the topological sectors at the very early stage of the flow ( $t^\approx 0.5$ -- $1$ ), suggesting that a further systematic investigation of the DBW2 flow is warranted to confirm its computational efficiency in determining the gauge topology.
↳ hep-lathep-thnucl-thJHEP(2025)·11 citations
08
Gluon Saturation Effects in Exclusive Heavy Vector Meson Photoproduction
Jani Penttala🇺🇸 · Christophe Royon🇺🇸
We study exclusive $J / ψ$ and $Υ$ photoproduction for proton and Pb targets in the high-energy limit, with the energy dependence computed using the linear Balitsky-Fadin-Kuraev-Lipatov and the nonlinear Balitsky-Kovchegov evolution equations. The difference between these two evolution equations can be directly attributed to gluon saturation physics. We find that for proton targets there is no difference between the two approaches at the energies of the currently available data, while for Pb targets in $J / ψ$ production the data shows a clear preference for the evolution with gluon saturation.
↳ hep-phnucl-thPLB(2025)·18 citations
09
Relative Hadron Yields in HRG With Medium Modification
Nasir Ahmad Rather🇮🇳 · Sameer Ahmad Mir🇮🇳 · Iqbal Mohi Ud Din🇮🇳 · Saeed Uddin🇮🇳
In the framework of a constituent quark mass model, the modified baryon masses are incorporated into the hadron resonance gas (HRG) based analysis of the like mass particle ratios in ultra relativistic nucleus-nucleus collisions (URNNC) over a wide range of collision energy. In addition we have incorporated an essential feature of the hadronic interaction at short distance, i.e. the hard-core repulsion by using the standard excluded volume type approach. We have extracted the chemical freeze-out conditions. The resulting freeze-out line in our case is compared with those obtained earlier using different model approaches. The correlation between $k^{-} / k^{+}$ and $p ˉ / p$ ratios is also studied.
↳ hep-phnucl-thInt.J.Mod.Phys.A(2025)·4 citations
10
Bayesian inference of strangeon matter using the measurements of PSR J0437-4715 and GW190814
Wen-Li Yuan🇨🇳 · Chun Huang🇺🇸 · Chen Zhang🇨🇳 · Enping Zhou🇨🇳 · Renxin Xu🇨🇳
The observations of compact star inspirals from LIGO/Virgo combined with mass and radius measurements from NICER provide a valuable tool to study the highly uncertain equation of state (EOS) of dense matter at the densities characteristic of compact stars. In this work, we constrain the solid states of strange-cluster matter, called strangeon matter, as the putative basic units of the ground state of bulk strong matter using a Bayesian statistical method, incorporating the mass and radius measurements of PSR J0030+0451, PSR J0740+6620, and the recent data for the $1.4 M_{⊙}$ pulsar PSR J0437-4715. We also include constraints from gravitational wave events GW170817 and GW190814. Under the prior assumption of a finite number of quarks in a strangeon, $N_{q}$ , our analysis reveals that current mass-radius measurements favor a larger $N_{q}$ . Specifically, the results support the scenario where a strangeon forms a stable bound state with $N_{q} = 18$ , symmetric in color, flavor, and spin spaces, compared to the minimum $N_{q}$ prior. The comparative analyses of the posterior EOS parameter spaces derived from three-parameter model and two-parameter model demonstrate a consistent prediction under identical observational constraints. In particular, our results indicate that the most probable values of the maximum mass are found to be $3.5 8_{- 0.12}^{+ 0.16} M_{⊙}$ ( $3.6 5_{- 0.16}^{+ 0.18} M_{⊙}$ ) at $90%$ confidence level for three-parameter (two-parameter) EOS considering the constraints of GW190814. The corresponding radii for $1.4 M_{⊙}$ and $2.1 M_{⊙}$ stars are $12.0 4_{- 0.31}^{+ 0.27} km$ ( $12.1 6_{- 0.31}^{+ 0.26} km$ ) and $13.4 3_{- 0.32}^{+ 0.31} km$ ( $13.6 0_{- 0.34}^{+ 0.29} km$ ), respectively. This result may impact interestingly on the research of multiquark states, which could improve our understanding of the nonperturbative strong force.
↳ astro-ph.HEnucl-thPRD(2025)·17 citations
11
Hyperons in neutron star mergers
Hristijan Kochankovski🇪🇸 · Angels Ramos🇪🇸 · Laura Tolos🇪🇸 · Sebastian Blacker🇩🇪 · Andreas Bauswein🇩🇪
We discuss the effects induced by the potential presence of hyperons in hot and ultra-dense matter within the context of neutron star mergers. Specifically, we address their effect on the dominant post-merger frequency of the gravitational waves. By performing a simulation campaign with a large sample of hyperonic and nucleonic equations of state, we explicitly show that the unique thermal behavior of hyperonic equations of state results in a systematic shift of the dominant frequency with respect to the nucleonic reference level. The predicted shift has values of up to 150 Hz, and it could be detected with the newest generations of gravitational wave detectors. Thus this approach opens a new path for signaling the presence of hyperons in neutron star remnant matter.
↳ hep-phnucl-thPoS(2025)·2 citations

Affiliations

first authorsco-authorsvia INSPIRE

Constraining Jet Quenching in Heavy-Ion Collisions with Bayesian Inference

CompactObject: An open-source Python package for full-scope neutron star equation of state inference

Lattice gradient flows (de-)stabilizing topological sectors

Gluon Saturation Effects in Exclusive Heavy Vector Meson Photoproduction

Relative Hadron Yields in HRG With Medium Modification

Bayesian inference of strangeon matter using the measurements of PSR J0437-4715 and GW190814

Hyperons in neutron star mergers

Affiliations