Nuclear Theory·nucl-th

Tuesday·July 1, 2025

15 papers—6 primary·9 cross-listed

07
Lattice study of correlators for quarkonium decay
Saumen Datta🇮🇳 · Debasish Banerjee🇬🇧 · Nora Brambilla🇩🇪 · Marc Janer🇩🇪 · Viljami Leino🇩🇪 · Julian Mayer-Steudte🇩🇪 · Peter Petreczky🇺🇸 · Balbeer Singh🇺🇸 · Antonio Vairo🇩🇪
While there has been a lot of progress in developing a formalism for the study of quarkonia in QGP, a nonperturbative study is still difficult. For bottomonia, where the system size is much less than the inverse temperature, the interaction of the system with the medium can be approximated by a dipole interaction with the color electric field. The decay of the quarkonia can be connected to a correlation function of the color electric field. We present preliminary results from a lattice study of the relevant color electric field correlator. The structure of the correlator, and its difference from the corresponding correlator studied for heavy quark diffusion, is discussed.
↳ hep-lathep-phnucl-thJ.Subatomic Part.Cosmol.(2025)·0 citations
08
The diffuse supernova neutrino background: an update with modern population synthesis and core-collapse simulations
Cecilia Lunardini🇺🇸 · Tomoya Takiwaki🇯🇵 · Tomoya Kinugawa🇯🇵 · Shunsaku Horiuchi🇯🇵 · Kei Kotake🇯🇵
We present a new, state-of-the-art computation of the Diffuse Supernova Neutrino Background (DSNB), where we use neutrino spectra from multi-dimensional, multi-second core collapse supernova simulations - including both neutron-star and black-hole forming collapses - and binary evolution effects from modern population synthesis codes. Large sets of numerical results are processed and connected in a consistent manner, using two key quantities: the mass of the star's Carbon-Oxygen (CO) core at an advanced pre-collapse stage - which depends on binary evolution effects - and the compactness parameter, which is the main descriptor of the post-collapse neutrino emission. The method enables us to model the neutrino emission of a very diverse, binary-affected population of stars, which cannot unambiguously be mapped in detail by existing core collapse simulations. We find that including black hole-forming collapses enhances the DSNB by up to 50% at energies greater than 30-40 MeV. Binary evolution effects can change the total rate of collapses and generate a sub-population of high core mass stars that are stronger neutrino emitters. However, the net effect on the DSNB is moderate - up to a 15% increase in flux - due to the rarity of these super-massive cores and to the relatively modest dependence of the neutrino emission on the CO core mass. The methodology presented here is suitable for extensions and generalizations, and therefore it lays the foundation for modern treatments of the DSNB.
↳ astro-ph.HEhep-phnucl-thPRD(2026)·6 citations
09
Study on Pentaqaurks by Solving Schrodinger Equation in the Non-Hermitian Quantum Mechanics
Bao-Xi Sun🇨🇳
The interaction of the charmed baryon and the anticharmed meson is assumed to be realized by exchanging a scalar meson of $f_{0} (500)$ , and then these systems are studied by solving the Schrodinger equation, respectively. When the pentaquarks $P_{c c ˉ} (4312)^{+}$ , $P_{c c ˉ} (4457)^{+}$ , $P_{c c ˉ s} (4338)^{0}$ , and $P_{c c ˉ s} (4459)^{0}$ are treated as $Σ_{c} D ˉ$ , $Σ_{c} D ˉ^{*}$ , $Ξ_{c} D ˉ$ and $Ξ_{c} D ˉ^{*}$ bound states, four resonance states of them are obtained as solutions of the Schrodinger equation under the outgoing wave condition, respectively. The resonance state of $Σ_{c} D ˉ$ might correspond to the particle $P_{c c ˉ} (4440)^{+}$ , while the other three resonance states have no counterparts in the review of the Particle Data Group(PDG). Although the binding energy of the bound state is only several MeVs, all these resonance states are more than 100 MeV higher than their corresponding thresholds, respectively. The calculation results indicate that the spectrums of the strange and non-strange pentaquarks are symmetric to each other.
↳ hep-phnucl-th0 citations
10
A generalized definition of the isothermal compressibility in (2+1)-flavor QCD
D. A. Clarke🇺🇸 · J. Goswami🇩🇪 · F. Karsch🇩🇪 · P. Petreczky🇺🇸
We introduce a generalized definition of the isothermal compressibility ( $κ_{T, σ_{Q}^{2}}$ ) calculable by keeping net conserved charge fluctuations rather than total number densities constant. We present lattice QCD results for this isothermal compressibility, expressed in terms of fluctuations of conserved charges that are related to baryon ( $B$ ), electric charge ( $Q$ ) and strangeness ( $S$ ) quantum numbers. This generalized isothermal compressibility is compared with hadron resonance gas model calculations as well as with heavy-ion collision data obtained at RHIC and the LHC. We find $κ_{T, σ_{Q}^{2}} = 13.8 (1.3)$ ~fm $^{3}$ /GeV at $T_{p c, 0} = 156.5 (1.5)$ ~MeV and $μ^_{B} = 0$ . This finding is consistent with the rescaled result of the ALICE Collaboration, where we replaced the number of charged hadrons ( $N_{ch}$ ) by the total number of hadrons ( $N_{tot}$ ) at freeze-out. Normalizing this result with the QCD pressure ( $P$ ) we find that the isothermal compressibility on the pseudo-critical line stays close to that of an {\it ideal gas}, {\it i.e.} $P κ_{T, σ_{Q}^{2}} ≃ 1$ .
↳ hep-lathep-phnucl-thPRD(2026)·3 citations
11
Direct proton transfer on $^{46}$ Ar supports the presence of a charge density bubble linked to a novel nuclear structure below $^{48}$ Ca
Daniele Brugnara (1,2)🇮🇹 · Andrea Gottardo (2)🇮🇹 · Marlene Assiè (3)🇫🇷 · Carlo Barbieri (4,5)🇮🇹 · Daniele Mengoni (1,6)🇮🇹 · Didier Beaumel (3)🇫🇷 · Stefano Brolli (4,5)🇮🇹 · Simone Bottoni (4,5)🇮🇹 · Emmanuel Clément (7)🇫🇷 · Gianluca Colò (4,5)🇮🇹 · Freddy Flavigny (8)🇫🇷 · Franco Galtarossa (3,6)🇫🇷 and 67 other authors
The $^{46}$ Ar( $^{3}$ He,d) $^{47}$ K reaction was performed in inverse kinematics using a radioactive $^{46}$ Ar beam produced by the SPIRAL1 facility at GANIL and a cryogenic $^{3}$ He target. The AGATA-MUGAST-VAMOS setup allowed the coincident measurement of the $γ$ rays, deuterons and recoiling $^{47}$ K isotopes produced by the reaction. The relative cross sections towards the proton-addition states in $^{47}$ K point towards a depletion of the $π s_{1/2}$ shell. The experimental findings are in good agreement with ab initio calculations, which predict that $^{46}$ Ar exhibits a charge density bubble associated with a pronounced proton closed-shell character.
↳ nucl-exnucl-th1 citation
12
Collective phenomena in chirally imbalanced medium
Sourav Duari🇮🇳 · Nilanjan Chaudhuri🇮🇳 · Sourav Sarkar🇮🇳 · Pradip Roy🇮🇳
We calculate the gluon polarization tensor for a chirally imbalanced plasma using hard thermal loop approximation in the real time formulation of thermal field theory. The dispersion relations obtained from the poles of the effective gluon propagator are solved numerically as well as analytically in appropriate limiting cases. It is seen that the degenerate transverse modes split into left and right handed circularly polarized modes. We also compute imaginary poles of the propagator which signal the presence of instability in the plasma. Relevant time scales for development of such instabilities are discussed in detail. Furthermore, we compute both the real and imaginary parts of the static heavy-quark potential in the chirally imbalanced plasma and argue that quarkonium suppression is enhanced due to the combined effects of a reduced debye screening length and an increased decay width. In addition, we calculate the gluon spectral density, sum rules and residues for various cases, providing a comprehensive understanding of the collective behaviour of the medium.
↳ hep-phnucl-thEPJA(2025)·5 citations
13
Nucleon mass: trace anomaly and $σ$ -terms
Martin Hoferichter🇨🇭 · Jacobo Ruiz de Elvira🇪🇸
We give a pedagogical introduction to the origin of the mass of the nucleon. We first review the trace anomaly of the energy-momentum tensor, which generates most of the nucleon mass via the gluon fields and thus contributes even in the case of vanishing quark masses. We then discuss the contributions to the nucleon mass that do originate from the Higgs mechanism via the quark masses, reviewing the current status of nucleon $σ$ -terms that encode the corresponding matrix elements.
↳ hep-phhep-exhep-latnucl-thEncyclopedia of Particle Physics·7 citations
14
Finite Gaussian assistance protocols and a conic metric for extremizing spacelike vacuum entanglement
Boyu Gao🇺🇸 · Natalie Klco🇺🇸
In a pure Gaussian tripartition, a range of entanglement between two parties ( $A B$ ) can be purified through classical communication of Gaussian measurements performed within the third ( $C$ ). To begin, this work introduces a direct method to calculate a hierarchic series of projective $C$ measurements for the removal of any $A B$ Gaussian noise, circumventing divergences in prior protocols. Next, a multimode conic framework is developed for pursuing the maximum (Gaussian entanglement of assistance, GEOA) or minimum (Gaussian entanglement of formation, GEOF) pure entanglement that may be revealed or required between $A B$ . Within this framework, a geometric necessary and sufficient entanglement condition emerges as a doubly-enclosed conic volume, defining a novel distance metric for conic optimization. Extremizing this distance for spacelike vacuum entanglement in the massless and massive free scalar fields yields (1) the highest known lower bound to GEOA, the first that decays slower than the two-point correlation functions and (2) the lowest known upper bound to GEOF, the first that decays exponentially mirroring the mixed $A B$ negativity. Furthermore, combination of the above with a generalization of previous partially-transposed noise filtering techniques allows calculation of a single $C$ measurement that maximizes the purified $A B$ entanglement. Beyond expectation that these behaviors of spacelike GEOA and GEOF persist in interacting theories, the present measurement and optimization techniques are applicable to physical many-body Gaussian states beyond quantum fields.
↳ quant-phhep-latnucl-thPRA(2026)·1 citation
15
Quark Recombination
Rainer J. Fries · Vincenzo Greco · Ralf Rapp
Hadronization is a fundamental process occurring at a distance scale of about $1 fm ≃ Λ_{QCD}^{- 1}$ , hence within non-perturbative dynamics. In elementary collisions, like $e^{+} e^{-}$ , $e^{-} p$ , or $pp$ , phenomenological approaches to hadronization have been developed based on vacuum-like dynamics that require the creation of quark-antiquark and/or diquark pairs during the hadronization process. In the 2000s, the idea was developed that in ultra-relativistic nucleus-nucleus (AA) collisions, which lead to the formation of a partonic medium with large (anti-)quark densities, hadronization can occur through the recombination of in-medium quarks, unlike the situation in $e^{+} e^{-}$ , $e^{-} p$ , and $pp$ . We give an overview of the main features that characterize quark recombination and have enabled a description of several important experimental observables at both RHIC and LHC over the last two decades. We highlight some additional developments and open issues. We specifically discuss the impact of coalescence on the study of heavy-flavor hadronization, including recent developments showing signatures of (the onset of) quark coalescence even in $pp$ collisions at TeV energies. Furthermore, we highlight specific features of hadronization for quarkonium in AA collisions, where it has been possible to develop a dynamical kinetic approach that allows to extract more detailed information about the temperature dependence of the heavy-quark interaction in hot QCD matter.
↳ hep-phhep-exnucl-exnucl-th6 citations

Affiliations

first authorsco-authorsvia INSPIRE