Nuclear Theory·nucl-th

Tuesday·August 13, 2024

16 papers—8 primary·8 cross-listed

09
[Submitted on 9 Aug 2024] (cross-list from astro-ph.HE)
Constraining twin stars with cold neutron star cooling data
Melissa Mendes🇩🇪 · Jan-Erik Christian🇩🇪 · Farrukh J. Fattoyev🇺🇸 · Jürgen Schaffner-Bielich🇩🇪
We investigate the influence of a phase transition from hadronic matter to a deconfined quark phase inside a neutron star on its cooling behaviour including the appearance of twin star solutions in the mass-radius diagram. We find that while the inferred neutrino luminosity of cold transiently-accreting star in MXB $1659 - 29$ is reproduced in all of the constructed twin star models, the luminosity of a colder source, the neutron star in SAX J $1808.4 - 3658$ , cannot be described by equations of state with quark-hadron transition densities below $1.7$ saturation density, suggesting that twin stars with such low density transitions to the quark phase are not realized in nature. We also discuss how constraints to the quark-hadron phase transition density are strongly dependent on the cooling effectiveness of neutrino reactions in the quark phase.
Comments:
11 pages, 6 figures. Accepted for publication in PRD
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2408.05287 [pdf]
PRD(2025)·13 citations
10
[Submitted on 10 Aug 2024] (cross-list from hep-ph)
Charged pions asymmetry from the decay of light neutral axial mesons due to interference
Fabio L. Braghin🇧🇷
Effective three meson couplings, based in flavor U(3) quark-antiquark interactions, are considered to describe two light neutral axial meson Strong decays, $A \sim f_{1} (1285)$ and $f_{1 S} (1420)$ , and the charged rho meson decay in the following channels: $A \to ρ^{\mp} (770) + π^{\pm}$ , $A \to a_{0}^{\mp} (980) + π^{\pm}$ and $ρ^{\pm} \to π^{\pm} π^{0}$ . By considering neutral meson mixings, such as $f_{1} (1285) - a_{1}^{0} (1260)$ , $f_{1 S} (1420) - a_{1}^{0} (1260)$ and $η - π^{0}$ for the channels investigated, the leading three-meson interactions may lead to decay amplitudes that undergo interference and a resulting ratio of decay rate into charged pions, $Γ_{π^{+}} / Γ_{π^{-}}$ , slightly smaller than one. For that it will be assumed that the produced charged vector mesons or charged scalar mesons undergo absorption, decay into channels without charged pions, or any other inelastic process that may suppress their decays into charged pions.
Comments:
17 pages, 9 figures, revised manuscript. Accepted for publication
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2408.05574 [pdf]
J.Phys.G(2025)·1 citation
11
[Submitted on 11 Aug 2024] (cross-list from astro-ph.SR)
Nuclear Burning in Accretion Flow of Helium-rich matter onto Compact Objects
Toshikazu Shigeyama · Akira Dohi
We investigate the impacts of nuclear burning on the spherically symmetric stationary accretion flow of helium-rich matter on to compact objects. We have already shown the existence of the critical accretion rates for the accretion of CO-rich matter above which the flow truncates in the supersonic region due to nuclear burning in the previous paper \citep{2022ApJ...933...29N}. Here, we show that there are also critical accretion rates for helium-rich matter. While we used empirical formulae for the energy generation rates for carbon burning and oxygen burning without solving the nuclear reaction network in our previous work, we solve a simple nuclear reaction network consisting of 13 elements from $^{4}$ He to $^{56}$ Ni to investigate influence of the energy generation from not only triple- $α$ reactions but also the subsequent reactions of synthesized elements. We have also qualitatively confirmed the previous results for CO-rich matter accretion using the revised code with the nuclear reaction network and reported some new findings.
Comments:
11 pages, 12 figures. To be submitted to The Publication of Astronomical Society of Japan
Subjects:
Solar and Stellar Astrophysics (astro-ph.SR); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2408.05666 [pdf]
0 citations
12
[Submitted on 12 Aug 2024] (cross-list from hep-lat)
Systematic Uncertainties from Gribov Copies in Lattice Calculation of Parton Distributions in the Coulomb gauge
Xiang Gao🇺🇸 · Jinchen He🇺🇸 · Rui Zhang🇺🇸 · Yong Zhao🇺🇸
Recently, it has been proposed to compute parton distributions from boosted correlators fixed in the Coulomb gauge within the framework of Large-Momentum Effective Theory. This method does not involve Wilson lines and could greatly improve the efficiency and precision of lattice QCD calculations. However, there are concerns about whether the systematic uncertainties from Gribov copies, which correspond to the ambiguity in lattice gauge-fixing, are under control. This work gives an assessment of the Gribov copies' effect in the Coulomb-gauge-fixed quark correlators. We utilize different strategies for the Coulomb-gauge fixing, selecting two different groups of Gribov copies based on the lattice gauge configurations. We test the difference in the resulted spatial quark correlators in the vacuum and a pion state. Our findings indicate that the statistical errors of the matrix elements from both Gribov copies, regardless of the correlation range, decrease proportionally to the square root of the number of gauge configurations. The difference between the strategies does not show statistical significance compared to the gauge noise. This demonstrates that the effect of the Gribov copies can be neglected in the practical lattice calculation of the quark parton distributions.
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2408.05910 [pdf]
Chin.Phys.Lett.(2024)·11 citations
13
[Submitted on 12 Aug 2024] (cross-list from cond-mat.quant-gas)
Quantum corrections at second order in derivatives to the dynamics of small non-relativistic fluids
Lars H. Heyen🇩🇪 · Giuliano Giacalone🇩🇪 · Stefan Floerchinger🇩🇪
To capture the dynamics of macroscopic non-relativistic fluids consisting of very many atoms, it is typically sufficient to truncate the gradient expansion at order zero, leading to ideal fluid dynamics, or at order one, leading to the Navier-Stokes theory. For mesoscopic fluids consisting of a small number of atoms, second-order corrections can become significant. We investigate here specifically superfluids at vanishing temperature, and identify relevant second-order terms of quantum origin that contribute already in a static situation. The general form of these terms arises from an extension of the Gross-Pitaevskii theory. In the context of density functional theory, they are named after C. von Weizsäcker. We assess the influence of these terms on numerical solutions of second-order fluid dynamic equations for the expansion of a mesoscopic ultra-cold Fermi gas released from an anisotropic harmonic trap in two spatial dimensions.
Subjects:
Quantum Gases (cond-mat.quant-gas); Nuclear Theory (nucl-th); Quantum Physics (quant-ph)
arXiv:
2408.06104 [pdf]
PRC(2025)·1 citation
14
[Submitted on 12 Aug 2024] (cross-list from hep-ph)
Nonperturbative four-gluon vertex in soft kinematics
A. C. Aguilar🇧🇷 · F. De Soto🇪🇸 · M. N. Ferreira🇨🇳 · J. Papavassiliou🇪🇸 · F. Pinto-Gómez🇪🇸 · J. Rodríguez-Quintero🇪🇸 · L. R. Santos🇧🇷
We present a nonperturbative study of the form factor associated with the projection of the full four-gluon vertex on its classical tensor, for a set of kinematics with one vanishing and three arbitrary external momenta. The treatment is based on the Schwinger-Dyson equation governing this vertex, and a large-volume lattice simulation, involving ten thousand gauge field configurations. The key hypothesis employed in both approaches is the ``planar degeneracy'', which classifies diverse configurations by means of a single variable, thus enabling their meaningful ``averaging''. The results of both approaches show notable agreement, revealing a considerable suppression of the averaged form factor in the infrared. The deviations from the exact planar degeneracy are discussed in detail, and a supplementary variable is used to achieve a more accurate description. The effective charge defined through this special form factor is computed within both approaches, and the results obtained are in excellent agreement.
Comments:
8 pages, 7 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Lattice (hep-lat); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2408.06135 [pdf]
PLB(2024)·9 citations
15
[Submitted on 12 Aug 2024] (cross-list from nucl-ex)
Prominent bump in the two-neutron separation energies of neutron-rich lanthanum isotopes revealed by high-precision mass spectrometry
A. Jaries🇫🇮 · M. Stryjczyk🇫🇮 · A. Kankainen🇫🇮 · T. Eronen🇫🇮 · O. Beliuskina🇫🇮 · T. Dickel🇩🇪 · M. Flayol🇫🇷 · Z. Ge🇫🇮 · M. Hukkanen🇫🇮 · M. Mougeot🇫🇮 · S. Nikas🇫🇮 · I. Pohjalainen🇫🇮 and 4 other authors
We report on high-precision atomic mass measurements of $^{148 - 153}$ La and $^{151}$ Ce performed with the JYFLTRAP double Penning trap using the Phase-Imaging Ion-Cyclotron-Resonance technique. The masses of $^{152, 153}$ La were experimentally determined for the first time. We confirm the sharp kink in the two-neutron separation energies at the neutron number $N = 93$ in the cerium ( $Z = 58$ ) isotopic chain. Our precision mass measurements of the most exotic neutron-rich lanthanum ( $Z = 57$ ) isotopes reveal a sudden increase in two-neutron separation energies from $N = 92$ to $N = 93$ . Unlike in the cerium isotopic chain, the kink is not sharp but extends to $N = 94$ forming a prominent bump. The gain in energy is about 0.4 MeV, making it one of the strongest changes in two-neutron separation energies over the whole chart of nuclides, away from nuclear shell closures. The results call for further studies to elucidate the structure of neutron-rich lanthanum isotopes.
Comments:
9 pages, 4 figures
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2408.06221 [pdf]
PRL(2025)·7 citations
16
[Submitted on 12 Aug 2024] (cross-list from hep-ph)
Dissecting Lepton Number Violating Interactions in the Left-Right Symmetric Model: $0 ν β β$ decay, Møller scattering, and collider searches
Gang Li🇨🇳 · Michael J. Ramsey-Musolf🇺🇸 · Sebastián Urrutia Quiroga🇺🇸 · Juan Carlos Vasquez🇺🇸
In the context of the left-right symmetric model, we study the interplay of neutrinoless double beta ( $0 ν β β$ ) decay, parity-violating Møller scattering, and high-energy colliders, resulting from the Yukawa interaction of the right-handed doubly-charged scalar to electrons, which could evade the severe constraints from charged lepton flavor violation. The $0 ν β β$ decay amplitude receives additional contributions from right-handed sterile neutrinos. The half-life, calculated in the effective field theory (EFT) framework, allows for an improved description of the contributions involving non-zero mixing between left- and right-handed $W$ bosons and those arising from exchanging a light right-handed neutrino. We find that the relative sensitivities between the low-energy (or high-precision) and high-energy experiments are affected by the left-right mixing. On the other hand, our results show how the interplay of collider and low-energy searches provides a manner to explore regions that are inaccessible to $0 ν β β$ decay experiments.
Comments:
12 pages, 6 figures. Modifications according to the referee's comments. Matches the accepted version in PLB
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2408.06306 [pdf]
PLB(2026)·8 citations

Affiliations

first authorsco-authorsvia INSPIRE