Nuclear Theory·nucl-th

Wednesday·July 2, 2025

15 papers—5 primary·10 cross-listed

06
[Submitted on 30 Jun 2025] (cross-list from astro-ph.HE)
Recurring region for neutron-star observables
Alexander Clevinger🇺🇸 · Zidu Lin🇺🇸 · Milena Albino🇵🇹 · Peter Hammond🇺🇸 · Veronica Dexheimer🇺🇸 · Andrew Steiner🇺🇸
In this letter, we report a novel, somewhat analytical way to produce equations of state (EOSs) that generate particular values of neutron star mass, radius, and tidal deformability. This is possible because our description for the EoS of dense matter can produce recurring regions, small areas where several EoSs cross in the mass-radius and mass-tidal deformability diagrams. We can place recurring regions in desired locations of these diagrams, corresponding e.g., to a given observation. Our prescription is versatile, in the sense that different microscopic models can be used for the low density hadronic phase and high density quark phase, as long as they are connected by a percolation, a description that mimics quark deconfinement and is motivated by QCD. The several EoSs that pass by a recurring region can present different thresholds for the boundaries of the percolation region (different beginning and ending for the quark deconfinement region), as well as different orders for the phase transition at the boundaries. When combining all these features, our prescription allows one not only to produce an EoS that matches an observation, but also one that matches specific chosen criteria for the EoS. The EoSs produced by this new method will be specially suitable for the study of dense-matter properties in future gravitational-wave observations, when both the inspiral and post-merger phase signals will become available. Our numerical code that calculates recurring regions using CompOSE microscopic EoSs is open source and publicly available.
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2506.24069 [pdf]
PRD(2026)·4 citations
07
[Submitted on 29 Jun 2025] (cross-list from quant-ph)
Studying few cluster resonances with quantum neural network driven iterative Harrow-Hassidim-Lloyd algorithm
Hantao Zhang🇨🇳 · Dong Bai🇨🇳 · Zhongzhou Ren🇨🇳
By using the quantum computing the properties of hypernuclei $_{Λ}^{5}$ He, $_{ΛΛ}^{6}$ He and $_{Λ}^{9}$ Be can be investigated within microscopic cluster model. Our approach combines quantum neural network (QNN) with iterative Harrow-Hassidim-Lloyd (IHHL) algorithm (abbreviated as QNN-IHHL) to solve the quantum many-body problem. To efficiently describe resonance phenomena, we employ complex scaling and eigenvector continuation techniques, providing a robust framework for identifying few-cluster resonance parameters within quantum computing. To validate our quantum algorithm, the resonant $4^{+}$ state of $_{Λ}^{9}$ Be is chosen as a core example. With QNN-IHHL algorithm we realize a fully quantum workflow, which provides a novel framework and some ground work for exploring resonance properties in complex nuclear many-body systems.
Subjects:
Quantum Physics (quant-ph); Nuclear Theory (nucl-th)
arXiv:
2507.00074 [pdf]
1 citation
08
[Submitted on 30 Jun 2025] (cross-list from hep-ph)
QCD antenna radiative spectrum in dense media within the Improved Opacity Expansion
Matvey V. Kuzmin🇷🇺 · João M. Silva🇪🇸
We compute the double differential inclusive spectrum for the emission of a soft gluon from a color-singlet $q q ˉ$ pair traversing a dense QCD medium. Our results extend the existing literature by simultaneously incorporating both single hard and multiple soft gluon exchanges between the jet and the medium -- an essential ingredient for a complete phenomenological description of jet quenching. Using the Improved Opacity Expansion framework, we provide an analytically tractable treatment, reducing the full cross-section to a set of simple expressions. Our analysis demonstrates that rare hard (Molière) scatterings significantly modify the gluon spectrum at large angles, accelerating the loss of color coherence between the initial quarks. We further quantify whether the modifications are driven by an overall weakening of the interference term, or by more detailed modifications to the fragmentation pattern. Our results provide a direct input for phenomenological jet quenching studies, offering new insights into the role of color decoherence in QCD matter.
Comments:
36 pages, 7 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2507.00143 [pdf]
JHEP(2025)·11 citations
09
[Submitted on 30 Jun 2025] (cross-list from hep-ph)
Entanglement, Trace Anomaly and Confinement in QCD
Kiminad A. Mamo🇺🇸
We formulate confinement in QCD as an entropic surface phenomenon. Quark and gluon quantum information is localized on a transverse entangling two-sphere of radius $R_{E E}$ ; at this radius the QCD vacuum -- partitioned by a hadron into interior and exterior regions -- reaches its maximal entanglement entropy. Lattice-QCD determinations of the scalar (trace) gravitational form factors fix both $R_{E E}$ and the transverse trace-anomaly density $ρ_{h} (R_{E E})$ , yielding a parameter-free slope $c_{h} = 8 π^{2} R_{E E}^{2} ρ_{h} (R_{E E})$ and a mechanical entropy $S_{E E} (y) = c_{h} y$ that grows linearly with rapidity $y$ . The entropy gradient $\partial_{R} S_{E E}$ changes sign at $R_{E E}$ : it pushes colored degrees of freedom outward for $r < R_{E E}$ and pulls them inward for $r > R_{E E}$ , thereby localizing them on the codimension-2 entangling two-sphere $Σ_{⊥} = S_{R_{E E}}^{2}$ (which, in the infinite-momentum frame, projects onto the transverse plane), the 'information wall'. This provides a high-energy (large- $y$ ) entropic confinement diagnostic that complements -- rather than replaces -- Wilson's area-law criterion, which probes long-distance dynamics near the rest frame ( $y \to 0$ ). Imposing unitarity on an entropic ansatz for the amplitude yields $σ (s) \propto y^{δ}$ . World data favor $δ = 2$ for elastic $pp (p p ˉ)$ scattering and heavy-quark photoproduction, whereas $ϕ$ photoproduction favors a softer $δ = 0.387$ . All extracted cross sections remain well below the Froissart--Martin bound. These results provide a confinement criterion quantified directly from non-perturbative QCD inputs, unifying the trace anomaly, entanglement entropy, and high-energy scattering within a single quantitative framework.
Comments:
v4: published version to Physical Review D (Letter)
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2507.00176 [pdf]
PRD(2025)·6 citations
10
[Submitted on 1 Jul 2025] (cross-list from hep-ph)
Susceptibilities of rotating quark matter in Fourier-Bessel basis
Mamiya Kawaguchi🇨🇳 · Kazuya Mameda🇯🇵
We analyze various two-point correlation functions of fermionic bilinears in a rotating finite-size cylinder at finite temperatures, with a focus on susceptibility functions. Due to the noninvariance of radial translation, the susceptibility functions are constructed using the Dirac propagator in the Fourier-Bessel basis instead of the plane-wave basis. As a specific model to demonstrate the susceptibility functions in an interacting theory, we employ the two-flavor Nambu-Jona-Lasinio model. We show that the incompatibility between the mean-field analysis and the Fourier-Bessel basis is evaded under the local density approximation, and derive the resummation formulas of susceptibilities with the help of a Ward-Takahashi identity. The resulting formulation reveals the rotational effects on meson, baryon number, and topological susceptibilities, as well as the moment of inertia. Our results may serve a useful benchmark for future lattice QCD simulations in rotating frames.
Comments:
27 pages, 8 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2507.00494 [pdf]
JHEP(2025)·4 citations
11
[Submitted on 1 Jul 2025] (cross-list from quant-ph)
Gravitational photon echo
Wen-Te Liao · Sven Ahrens
The generation, controls, and storage of the gravitationally induced photon echo using the 8.4 eV Thorium-229 nuclear clock transition on Earth are theoretically investigated. With its exceptionally narrow linewidth of approximately 1 mHz and high quality factor in the order of $1 0^{19}$ , the Thorium-229 clock transition allows for the potential detection of gravitational-redshift effects at millimeter-scale altitude variations. Moreover, the 1740-second half lifetime of the Thorium-229 isomeric state allows for the slow movement of the system within its coherence time. Along this line, we explore the generation, controls, and storage of photon echo arising from a rotation induced inversion of the gravitational frequency shift in a single target or in multiple equally spaced samples. Our approach lays the foundation for the controllable gravitational quantum optics on Earth.
Comments:
5 pages, 4 figures
Subjects:
Quantum Physics (quant-ph); General Relativity and Quantum Cosmology (gr-qc); Nuclear Theory (nucl-th)
arXiv:
2507.00533 [pdf]
0 citations
12
[Submitted on 1 Jul 2025] (cross-list from nucl-ex)
Energy dependence of rescattering effect on vector mesons spin alignment at RHIC
Zihan Liu🇨🇳 · Ziyang Li🇨🇳 · Wangmei Zha🇨🇳 · Zebo Tang🇨🇳
Spin alignment of vector mesons in heavy-ion collisions provides a novel probe of quark polarization and hadronization mechanism in quark-gluon plasma. Hadronic rescattering may affect the measured spin alignment of vector mesons due to non-uniform rescattering probability in non-central heavy-ion collisions. Using the UrQMD model, we systematically investigated the hadronic rescattering effect on the measurement of $ρ_{00}$ , the spin alignment parameter, for $K^{* 0}$ , $ϕ$ , and $ρ^{0}$ mesons in Au+Au collisions at $s_{NN}$ = 7.7 - 200 GeV. Our results reveal that the measurable $ρ_{00} - 1/3$ remains unaffected for $ϕ$ , while shows significantly negative (positive) deviations for $K^{* 0}$ and $ρ^{0}$ with respect to the reaction (production) plane. Quantitatively, the maximum deviation reaches $- 0.0056$ ( $0.0268$ ) for $K^{* 0}$ and $- 0.0122$ ( $0.0414$ ) for $ρ^{0}$ with respect to the reaction (production) plane. Notably, the deviations in $ρ_{00}$ for both $K^{* 0}$ and $ρ^{0}$ increase monotonically with increasing collision energy. These findings underscore the critical necessity of accounting for rescattering effects when interpreting spin alignment measurements of short-lived vector mesons in heavy-ion collisions.
Comments:
9 pages, 8 figures
Subjects:
Nuclear Experiment (nucl-ex); High Energy Physics — Experiment (hep-ex); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2507.00706 [pdf]
PLB(2026)·3 citations
13
[Submitted on 1 Jul 2025] (cross-list from astro-ph.HE)
Hybrid Quark Stars with Quark-Quark Phase Transitions
Zongcan Yang🇨🇳 · Tianxiong Zeng🇨🇳 · Yan Yan🇨🇳 · Wen-Li Yuan🇨🇳 · Chen Zhang🇨🇳 · Enping Zhou🇨🇳
We explore the possibility of phase transitions between different quark matter phases occurring within quark stars, giving rise to the hybrid quark stars (HybQSs). First, we obtain the generic phase diagram of possible mass-radius relation forms for the HybQSs. Then, utilizing a well-established general parameterization of interacting quark matter, we construct quark star models featuring sharp first-order quark-quark phase transitions of various types, in contrast to the hadron-quark transition in conventional hybrid stars. We systematically investigate how recent observations, such as the pulsar mass measurement $M_{TOV} ≳ 2 M_{⊙}$ and the GW170817's tidal deformability bound $Λ_{1.4 M_{⊙}} < 800$ , constrain the viable parameter space. We also identified twin stars in some of the HybQS parameter space. Furthermore, we found that the quark-quark phase transitions in hybrid quark stars may also cause the deviation from the approximate universal relation between the dominant postmerger frequency $f_{peak}$ and tidal deformability $Λ_{1.35 M_{⊙}}$ , which was previously believed to only be caused by the hadron-quark phase transitions in hybrid neutron stars. This work unveils new possibilities of phase transitions and the resulting new types of compact stars in realistic astrophysical scenarios.
Comments:
13 pages, 7 figures; updated version with possible signatures of gravitational wave astronomy
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2507.00776 [pdf]
PRD(2026)·11 citations
14
[Submitted on 1 Jul 2025] (cross-list from hep-ph)
Burgers equation for the bulk viscous pressure of quark matter
José Luis Hernandez🇪🇸 · Cristina Manuel🇪🇸 · Saga Säppi🇪🇸 · Laura Tolos🇪🇸
The dissipative properties of relativistic strongly interacting nuclear matter significantly influence the damping of stellar oscillations and density fluctuations during compact star mergers. In this work, we derive the evolution equation for the bulk viscous pressure in unpaired quark matter under small deviations from equilibrium. Our analysis reveals that it behaves like a two-component Burgers fluid. We identify four key transport coefficients -- two relaxation times and two bulk viscosity coefficients -- expressed in terms of equilibrium parameters and electroweak nonleptonic and semi-leptonic decay rates. The transport coefficients are evaluated for two distinct equations of state: one based on perturbative quantum chromodynamics and the other on a modified MIT bag model, valid in different density regimes. We also determine the temperature and density region where nonleptonic electroweak processes dominate the dissipation. Our formulation establishes a new way of describing bulk viscous effects in quark matter, applicable for numerical simulations of compact star mergers.
Comments:
10 pages, 4 figures. V2: Minor changes in text for published version, added data availability statement, fixed misprint in eq. (A2)
Subjects:
High Energy Physics — Phenomenology (hep-ph); General Relativity and Quantum Cosmology (gr-qc); Nuclear Theory (nucl-th)
arXiv:
2507.00794 [pdf]
PRD(2026)·7 citations
15
[Submitted on 1 Jul 2025] (cross-list from hep-ph)
Interplay of prompt and non-prompt photons in photon-triggered jet observables
Chathuranga Sirimanna🇺🇸 · Yasuki Tachibana · Abhijit Majumder · Aaron Angerami · Ritu Arora · Steffen Bass · Yi Chen · Ritoban Datta · Lipei Du · Raymond Ehlers · Hannah Elfner · Rainer J. Fries and 40 other authors
Prompt photons are important yet challenging to observe in relativistic heavy-ion collisions, as they are produced in the early stages and traverse almost the entire QGP medium without interaction. Experimental analyses typically employ isolation cuts, in the hope to identify prompt photons. Most theoretical studies consider only events with actual prompt photons, assuming no contribution from isolated non-prompt photons to reduce computational cost. For the first time, we present a study that compares simulation results generated using inclusive (bremsstrahlung) and prompt-photon events with multiple experimental observables for both $p - p$ and $P b - P b$ collisions at $5.02$ TeV. Simulations are carried out using the multi-stage JETSCAPE framework tuned to describe the quenching of jets and hadrons. Isolated non-prompt photons are generated in hard photon bremsstrahlung, where the photon is radiated at a sufficient angle to the jet. Several photon triggered jet and jet substructure observables show significant contributions from inclusive photons, yielding an improvement in comparison with experimental data. Novel photon triggered jet substructure observables are also expected to show new structures, yet to be detected in experiment. This effort examines the significance of isolated non-prompt photons using parameters tuned for a simultaneous description of the leading hadron and jet spectrum, and thus provides an independent verification of the multistage evolution framework.
Comments:
5 pages, 4 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2507.00905 [pdf]
EPJ Web Conf.(2025)·0 citations

Affiliations

first authorsco-authorsvia INSPIRE