Nuclear Theory·nucl-th

Monday·March 24, 2025

15 papers—8 primary·7 cross-listed

09
[Submitted on 20 Mar 2025] (cross-list from hep-ph)
Virtual Majorana Neutrinos and the Minimum Neutrino Mass Scale in Neutrinoless Double-Beta Decay
Dongming Mei🇺🇸 · Kunming Dong🇺🇸 · Austin Warren🇺🇸 · Sanjay Bhattarai🇺🇸
Virtual Majorana neutrinos are indispensable for neutrinoless double-beta (0 $ν β β$ ) decay. In this study, we demonstrate that the overlap of the virtual Majorana neutrino wavefunction, predominantly composed of a right-handed antineutrino component with a strongly suppressed left-handed component (with amplitude proportional to the effective Majorana neutrino mass, $∣ m_{β β} ∣$ , is crucial for triggering this decay process. This effective mass, derived from the minimum neutrino mass, offers valuable insights into the absolute neutrino mass scale. Using best-fit parameters from neutrino oscillation experiments, the minimum neutrino mass is determined from the sum of the three neutrino mass eigenstates, $Σ = m_{1} + m_{2} + m_{3},$ which is represented by two narrow bands centered at approximately 0.06 eV/c $^{2}$ for the normal hierarchy (NH) and 0.102 eV/c $^{2}$ for the inverted hierarchy (IH). Under these constraints, the minimum neutrino mass is found to be 0.001186 eV/c $^{2}$ for NH and 0.002646 eV/c $^{2}$ for IH, thereby establishing a potential absolute neutrino mass scale for both scenarios. From these values, we calculate $∣ m_{β β} ∣$ , which plays a central role in $0 ν β β$ decay. By combining $∣ m_{β β} ∣$ with decay phase-space factors, nuclear matrix elements, and the absorption probability of the virtual Majorana neutrino, we estimate the $0 ν β β$ half-life for key isotopes, namely, $^{76}$ Ge, $^{130}$ Te, and $^{136}$ Xe, using two independent methods. The results are in good agreement, and we also discuss the uncertainties in the nuclear matrix elements that may affect these calculations.
Comments:
11 pages, 7 figures, and 3 tables
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2503.16650 [pdf]
0 citations
10
[Submitted on 21 Mar 2025] (cross-list from hep-ph)
Shear and bulk viscous coefficients of a hot and chirally imbalanced quark matter using NJL model
Snigdha Ghosh🇮🇳 · Nilanjan Chaudhuri🇮🇳 · Pradip Roy🇮🇳 · Sourav Sarkar🇮🇳
The shear $η$ and bulk $ζ$ viscous coefficients have been calculated in a hot and chirally asymmetric quark matter quantified in terms of a chiral chemical potential (CCP) using the two-flavor Nambu-Jona--Lasinio (NJL) model. This is done by employing the one-loop Green-Kubo formalism where the viscous coefficients have been extracted from the long-wavelength limit of the in-medium spectral function corresponding to the energy momentum tensor (EMT) current correlator calculated using the real time formalism of finite temperature field theory. The momentum dependent thermal width of the quark/antiquark that enters into the expression of the viscosities as a dynamical input containing interactions, has been obtained from the $2 \to 2$ scattering processes mediated via the collective mesonic modes in scalar and pseudoscalar chanels encoded in respective in-medium polarization functions having explicit temperature and CCP dependence. Several thermodynamic quantities such as pressure, energy density, entropy density $(s)$ , specific heat and isentropic speed of sound have also been calculated at finite CCP. The temperature and CCP dependence of the viscosity to entropy density ratios $η / s$ and $ζ / s$ have also been studied.
Comments:
Version published in Physical Review D
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2503.16769 [pdf]
PRD(2025)·4 citations
11
[Submitted on 21 Mar 2025] (cross-list from hep-ph)
Anisotropic flows of identified hadrons in the equal-velocity quark combination model at RHIC energy
Yan-ting Feng🇨🇳 · Rui-qin Wang🇨🇳 · Feng-lan Shao🇨🇳 · Jun Song🇨🇳
We employ an equal-velocity quark combination model to study anisotropic flows $v_{2}$ , $v_{3}$ and $v_{4}$ of identified hadrons at mid-rapidity in heavy-ion collisions at RHIC energies. Under the equal-velocity combination mechanism of constituent quarks at hadronization, we build analytical formulas of anisotropic flows of hadrons in terms of those of quarks just before hadronization. We systematically analyze the contribution of higher order flows of quarks, and show how simple formulas of $v_{2}$ , $v_{3}$ and $v_{4}$ of identified hadrons with the desired precision can be obtained by neglecting the small contribution of higher order flows of quarks. We systematically test these simple formulas of hadronic flows by the experimental data of $v_{2}$ , $v_{3}$ and $v_{4}$ of identified hadrons $ϕ$ , $Λ$ , $Ξ^{-}$ , $Ω^{-}$ , $Λ ˉ$ , $Ξ ˉ^{+}$ , $Ω ˉ^{+}$ , $p$ and $p ˉ$ in Au+Au collisions at $s_{N N} =$ 19.6, 54.4 and 200 GeV, and we find that the equal-velocity quark combination model can well describe the measured $v_{2}$ , $v_{3}$ and $v_{4}$ of identified hadrons in Au+Au collisions at those collision energies. We further study the obtained anisotropic flows of quarks and find two scaling properties\textcolor{red}{{} }which can be qualitatively understood by the hydrodynamic evolution of thermal quark medium produced in relativistic heavy-ion collisions.
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2503.16804 [pdf]
PRC(2025)·2 citations
12
[Submitted on 21 Mar 2025] (cross-list from hep-ph)
Glueballonia as Hopfions
Yuki Amari🇯🇵 · Muneto Nitta🇯🇵 · Chihiro Sasaki🇯🇵 · Kenta Shigaki🇯🇵 · Satoshi Yano🇯🇵 · Shigehiro Yasui🇯🇵
We work out the Hopfion description of glueballs by inclusively comparing the energy spectra obtained by quantizing Hopfions with experimental data and lattice QCD. Identifying a Hopfion carrying a unit topological charge as $f_{0} (1500)$ , the Hopfions with the topological charge two are classified as glueballonia, i.e., two glueballs are bound together. We find a tightly and a loosely bound glueballonia complying with $f_{0} (2470)$ and a novel scalar particle carrying the mass around 2814 MeV, respectively, and calculate their binding energies. By the rigid body quantization of Hopfions, we predict a characteristic multiplet structure of tensor glueball states. Some of them are missing in the current experimental data and can be verified in future measurements.
Comments:
6+6 pages, 6 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2503.16810 [pdf]
PLB(2025)·3 citations
13
[Submitted on 21 Mar 2025] (cross-list from hep-ph)
Investigation of $Δ (1232)$ resonance substructure in $p γ^{*} \to Δ (1232)$ process through helicity amplitudes
A. Kaewsnod🇹🇭 · K. Xu🇹🇭 · T. Sangkhakrit🇹🇭 · Z. Zhao🇹🇭 · W. Sreethawong🇹🇭 · A. Limphirat🇹🇭 · K. Khosonthongkee🇹🇭 · Y. Yan🇹🇭
This work investigates the substructure of the $Δ (1232)$ resonance in the $p γ^{*} \to Δ (1232)$ process through helicity transition amplitudes within the quark model framework. We consider the involved baryons composed of three quarks, and both the quark core and meson cloud contribute to the transition amplitudes. The comparison of theoretical results with experimental data reveals that, rather than the $L = 0$ component of the $Δ (1232)$ resonance, it is the $L = 2$ component that significantly affects its $S_{1/2}$ amplitude. These findings indicate that the $Δ (1232)$ resonance likely contains a substantial $L = 2$ component, challenging the conventional view of the $Δ (1232)$ resonance as an $L = 0$ baryon.
Comments:
6 pages, 5 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2503.16838 [pdf]
PRD(2026)·0 citations
14
[Submitted on 21 Mar 2025] (cross-list from hep-ph)
QCD Phase Diagram for Large $N_{f}$ : Analysis from Contact Interaction Effective Potential
Aftab Ahmad🇵🇰
In this paper, we discuss the impact of a higher number of light quark flavors, $N_{f}$ , on the QCD phase diagram under extreme conditions. Our formalism is based on the Schwinger-Dyson equation, employing a specific symmetry-preserving vector-vector flavor-dressed contact interaction model of quarks in Landau gauge, utilizing the rainbow-Ladder truncation. We derive expressions for the dressed quark mass $M_{f}$ and effective potential $Ω^{f}$ at zero, at finite temperature $T$ and the quark chemical potential $μ$ . The transition between chiral symmetry breaking and restoration is triggered by the effective potential of the contact interaction, whereas the confinement and deconfinement transition is approximated from the confinement length scale $τ ~_{i r}$ . Our analysis reveals that at $(T = μ = 0)$ , increasing $N_{f}$ leads to the restoration of chiral symmetry and the deconfinement of quarks when $N_{f}$ reaches its critical value, $N_{f}^{c} \approx 8$ . At this critical value, In the chiral limit ( $m_{f} = 0$ ), the global minimum of the effective potential occurs at the point where the dressed quark mass approaches zero ( $M_{f} \to 0$ ). However, when a bare quark mass of $m_{f} = 7$ MeV is introduced, the global minimum shifts slightly to a nonzero value, approaching $M_{f} \to m_{f}$ . At finite $T$ and $μ$ , we illustrate the QCD phase diagram in the $(T_{c}^{χ, C} - μ)$ plane, for various numbers of light quark flavors, noting that both the critical temperature $T_{c}$ and the critical chemical potential $μ_{c}$ for chiral symmetry restoration and deconfinement decrease as $N_{f}$ increases. Moreover, the critical endpoint $(T_{E P}, μ_{E P})$ also shifts to lower values with increasing $N_{f}$ . Our findings are consistent with other low-energy QCD approaches.
Comments:
15 pages, 23 figures,Paper "Accepted"
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2503.16903 [pdf]
Rev.Mex.Fis.(2026)·2 citations
15
[Submitted on 21 Mar 2025] (cross-list from hep-lat)
Quantum fluctuations of quarks and gluons in nuclei
Michael L. Wagman🇺🇸
Acceptance talk for the 2024 Kenneth G. Wilson Award for Excellence in Lattice Field Theory: For key contributions to lattice QCD studies of noise reduction in nuclear systems, the structure of nuclei, and transverse-momentum dependent hadronic structure functions.
Comments:
Proceedings of the 41st International Symposium on Lattice Field Theory (Lattice 2024), 28 July - 3 August 2024, Liverpool, UK
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2503.17154 [pdf]
PoS(2025)·0 citations

Affiliations

first authorsco-authorsvia INSPIRE

Virtual Majorana Neutrinos and the Minimum Neutrino Mass Scale in Neutrinoless Double-Beta Decay

Shear and bulk viscous coefficients of a hot and chirally imbalanced quark matter using NJL model

Anisotropic flows of identified hadrons in the equal-velocity quark combination model at RHIC energy

Glueballonia as Hopfions

Investigation of Δ(1232) resonance substructure in pγ∗→Δ(1232) process through helicity amplitudes

QCD Phase Diagram for Large Nf​ : Analysis from Contact Interaction Effective Potential

Quantum fluctuations of quarks and gluons in nuclei

Affiliations

Investigation of $Δ (1232)$ resonance substructure in $p γ^{*} \to Δ (1232)$ process through helicity amplitudes

QCD Phase Diagram for Large $N_{f}$ : Analysis from Contact Interaction Effective Potential