Nuclear Theory·nucl-th

Tuesday·February 18, 2025

10 papers—3 primary·7 cross-listed

04
Nuclear Fusion Enhancement by Heavy Nuclear Catalysts
Christopher Grayson🇭🇺 · Johann Rafelski🇺🇸
We seek to understand the effect of high electron density in the proximity of a heavy nucleus on the fusion reaction rates in a hot plasma phase. We investigate quantitatively the catalytic effect of gold ( $Z = 79$ ) ions embedded in an electron plasma created due to plasmonic focusing of high-intensity short laser pulses. Using self-consistent strong plasma screening, we find highly significant changes in the internuclear potential of light elements present nearby. For gold, we see a $14$ keV change in the internuclear potential near the nuclear surface, independent of the long-distance thermal Debye-Hückel screening. The dense polarization cloud of electrons around the gold catalyst leads to a $\sim 1.5$ enhancement of proton-boron ( $^{11}$ B) fusion above $T = 100$ keV.
↳ physics.plasm-phastro-ph.SRnucl-thEur.Phys.J.ST(2025)·2 citations
05
Lattice QCD constraints on the critical point from an improved precision equation of state
Szabolcs Borsanyi🇩🇪 · Zoltan Fodor🇩🇪 · Jana N. Guenther🇩🇪 · Paolo Parotto🇮🇹 · Attila Pasztor🇭🇺 · Claudia Ratti🇺🇸 · Volodymyr Vovchenko🇺🇸 · Chik Him Wong🇩🇪
In this Letter we employ lattice simulations to search for the critical point of quantum chromodynamics (QCD). We search for the onset of a first order QCD transition on the phase diagram by following contours of constant entropy density from imaginary to real chemical potentials under conditions of strangeness neutrality. We scan the phase diagram and investigate whether these contours meet to determine the probability that the critical point is located in a certain region on the $T - μ_{B}$ plane. To achieve this we introduce a new, continuum extrapolated equation of state at zero density with improved precision using lattices with $N_{τ} = 8, 10, 12, 16$ timeslices, and supplement it with new data at imaginary chemical potential. The current precision allows us to exclude, at the $2 σ$ level, the existence of a critical point at $μ_{B} < 450$ ~MeV.
↳ hep-latnucl-thPRD(2025)·60 citations
06
Complex potential and open system applications in heavy-ions and cold atoms
Yukinao Akamatsu🇯🇵
Since the discovery of the complex potential of quarkonium at high temperatures, quarkonium has been regarded as an open quantum system in the quark-gluon plasma. Recently, a similar issue regarding in-medium bound states of impurities has also emerged in particle physics and cold atomic physics. We will provide an overview of recent advancements in understanding key quantities such as complex potential and transport coefficients for heavy impurities in finite temperature QCD and cold atomic systems.
↳ hep-phcond-mat.quant-gashep-exnucl-thPoS(2025)·0 citations
07
Heavy-flavor multimodal fragmentation to $S$ -wave pentacharms at next-generation hadron colliders
Francesco Giovanni Celiberto🇪🇸
We investigate the leading-power fragmentation of fully charmed pentaquark states ( $S$ -wave $∣ c c ˉ ccc ⟩$ pentacharms) at hadron colliders. We introduce a new set of multimodal collinear fragmentation functions, named PQ5Q1.0. They rely on an enhanced calculation of the initial-scale input for the constituent heavy-quark fragmentation channel, making them well suited to describe the short-distance emission of either a compact multicharm state or a dicharm-charm-dicharm configuration. To explore phenomenological implications, we use the (sym)JETHAD multimodular interface to study NLL/NLO $^{+}$ semi-inclusive production rates for pentacharm-plus-jet systems at the forthcoming HL-LHC and the future FCC. Our analysis represents a further step toward bridging the domains of hadronic structure, precision QCD, and exotic matter.
↳ hep-phhep-exhep-thnucl-ex+1EPJC(2025)·15 citations
08
Flavor dependence of Energy-energy correlators
Liliana Apolinário🇵🇹 · Raghav Kunnawalkam Elayavalli🇺🇸 · Nuno Olavo Madureira🇵🇹 · Jun-Xing Sheng🇺🇸 · Xin-Nian Wang🇨🇳 · Zhong Yang🇺🇸
Energy-energy correlators (EECs) within high energy jets serve as a key experimentally accessible quantity to probe the scale and structure of the quark-gluon plasma (QGP) in relativistic heavy-ion collisions. The CMS Collaboration's first measurement of the modification to the EEC within single inclusive jets in Pb+Pb collisions relative to p+p collisions reveals a significant enhancement at small angles, which may arise from jet transverse momentum $p_{T}$ selection biases due to jet energy loss. We investigate the dependence of jet EECs on the flavor of the initiating parton. The EEC distribution of a gluon jet is broader and the peak of transition from perturbative to non-perturbative regime occurs at a larger angle than a quark jet. Such flavor dependence leads to the different EECs for $γ$ -jets and single inclusive jets due to their different flavor composition. It is also responsible for a colliding energy dependence of EECs of single inclusive jets at fixed jet energy. We also investigate the impact of flavor composition variation on the $p_{T}$ dependence of the jet EEC. We further propose that a change in the gluon jet fraction in A+A collisions compared to p+p can also contribute to a non-negligible enhancement of the medium modified EEC at small angles. Using the \textsc{Jewel} model, we predict the reduction of the gluon jet fraction in A+A collisions and estimate its impact on the EEC.
↳ hep-phnucl-thPRD(2025)·29 citations
09
Constraining first-order phase transition inside neutron stars with application of Bayesian techniques on PSR J0437-4715 NICER data
Chun Huang · Shashwat Sourav
Understanding the existence of exotic matter phases and phase transitions within the core of neutron stars is crucial to advancing our knowledge of cold-dense matter physics. Recent multi-messenger observations, including gravitational waves from neutron star mergers and precise X-ray data from NASA's Neutron Star Interior Composition Explorer (NICER) mission, have significantly constrained the neutron star equation of state (EOS). This study investigates the effects of phase transitions in neutron stars, focusing on NICER's latest observation of PSR J0437--4715. We employ Bayesian inference techniques to evaluate the presence of first-order phase transitions using a piecewise polytropic EOS model. Our analysis incorporates data from multiple NICER sources, to refine constraints on key phase transition parameters, including critical density and transition depth. We find that including data from PSR J0437--4715 improves the evidence of phase transitions and tightens the EOS constraints, especially at higher densities. However, Bayes factor analysis only indicates a slight preference for models without phase transitions and current observational precision is insufficient to draw definitive conclusions. In particular, this polytropic model identifies the critical phase transition mass of neutron stars as being close to 1.4 solar masses, which coincides with the approximate mass range of PSR J0437--4715. This work emphasizes the importance of precise measurements of PSR J0437--4715 for deepening our understanding of neutron star interiors and exploring potential new physics at extreme densities.
↳ astro-ph.HEastro-ph.SRnucl-thApJ(2025)·24 citations
10
Lattice QCD Study of Pion Electroproduction and Weak Production from a Nucleon
Yu-Sheng Gao🇨🇳 · Zhao-Long Zhang🇨🇳 · Xu Feng🇨🇳 · Lu-Chang Jin🇺🇸 · Chuan Liu🇨🇳 · Ulf-G.Meißner🇩🇪
Quantum fluctuations in QCD influence nucleon structure and interactions, with pion production serving as a key probe of chiral dynamics. In this study, we present a lattice QCD calculation of multipole amplitudes at threshold, related to both pion electroproduction and weak production from a nucleon, using two gauge ensembles near the physical pion mass. We develop a technique for spin projection and construct multiple operators for analyzing the generalized eigenvalue problem in both the nucleon-pion system in the center-of-mass frame and the nucleon system with nonzero momentum. The numerical lattice results are then compared with those extracted from experimental data and predicted by low-energy theorems incorporating one-loop corrections.
↳ hep-lathep-phnucl-thPRL(2025)·7 citations

Affiliations

first authorsco-authorsvia INSPIRE

Nuclear Fusion Enhancement by Heavy Nuclear Catalysts

Lattice QCD constraints on the critical point from an improved precision equation of state

Complex potential and open system applications in heavy-ions and cold atoms

Heavy-flavor multimodal fragmentation to S-wave pentacharms at next-generation hadron colliders

Flavor dependence of Energy-energy correlators

Constraining first-order phase transition inside neutron stars with application of Bayesian techniques on PSR J0437-4715 NICER data

Lattice QCD Study of Pion Electroproduction and Weak Production from a Nucleon

Affiliations

Heavy-flavor multimodal fragmentation to $S$ -wave pentacharms at next-generation hadron colliders