Nuclear Theory·nucl-th

Thursday·May 30, 2024

7 papers—3 primary·4 cross-listed

01
Ab-initio electroweak corrections to superallowed $β$ decays and their impact on $V_{u d}$
Vincenzo Cirigliano🇺🇸 · Wouter Dekens🇺🇸 · Jordy de Vries🇳🇱 · Stefano Gandolfi🇺🇸 · Martin Hoferichter🇨🇭 · Emanuele Mereghetti🇺🇸
Radiative corrections are essential for an accurate determination of $V_{u d}$ from superallowed $β$ decays. In view of recent progress in the single-nucleon sector, the uncertainty is dominated by the theoretical description of nucleus-dependent effects, limiting the precision that can currently be achieved for $V_{u d}$ . In this work, we provide a detailed account of the electroweak corrections to superallowed $β$ decays in effective field theory (EFT), including the power counting, potential and ultrasoft contributions, and factorization in the decay rate. We present a first numerical evaluation of the dominant corrections in light nuclei based on Quantum Monte Carlo methods, confirming the expectations from the EFT power counting. Finally, we discuss strategies how to extract from data the low-energy constants that parameterize short-distance contributions and whose values are not predicted by the EFT. Combined with advances in ab-initio nuclear-structure calculations, this EFT framework allows one to systematically address the dominant uncertainty in $V_{u d}$ , as illustrated in detail for the $^{14}$ O $\to$ $^{14}$ N transition.
nucl-thhep-exhep-lathep-ph+1PRC(2024)·42 citations
02
Neutron skin impurity from Coulomb core polarization in $^{208} Pb$ : Insights from PREX-II and validation via the $(^{3} He, t)$ isobaric analog state reaction
Phan Nhut Huan
I investigate the effect of Coulomb core-polarization in $^{208} Pb$ , highlighting its impact on uncertainties in neutron distribution measurements due to the discrepancy between neutron excess and neutron skin regions at the surface. This effect is validated using the $(^{3} He, t)$ isobaric analog state (IAS) reaction at 420 MeV. My findings reveal that the Coulomb boundary radius, where core-polarization becomes negligible, is critical for accurately probing the neutron skin region in the target nucleus. Consequently, I propose extending the $^{208} Pb (^{3} He, t)$ IAS reaction experiment conducted by Zegers et al. [Phys. Rev. Lett. 99, 202501 (2007)] to measure cross sections up to 3 $^{\circ}$ angles to more precisely determine the neutron skin thickness in $^{208} Pb$ from theoretical reaction analysis. Additionally, I observe that, under the assumption of a large neutron skin in $^{208} Pb$ , as suggested by the PREX-II result, the core-polarization effect introduces impurity into the neutron skin region.
nucl-thnucl-exPRC(2024)·2 citations
03
An $ab initio$ strategy for taming nuclear-structure dependence of $V_{u d}$ extractions: the $^{10} C \to^{10} B$ superallowed transition
Michael Gennari🇨🇦 · Mehdi Drissi🇨🇦 · Mikhail Gorchtein🇩🇪 · Petr Navratil🇨🇦 · Chien-Yeah Seng🇺🇸
We report the first \textit{ab initio} calculation of the nuclear-structure-dependent radiative correction $δ_{NS}$ to the $^{10} C \to^{10} B$ superallowed transition, computed with the no-core shell model and chiral effective field theory. We obtain $δ_{NS} = - 0.422 (29)_{nuc} (12)_{n, el}$ with a $1.6$ -times reduction in the total uncertainty when compared to the current literature estimate based on the shell model and Fermi gas picture. This work paves the way for a precise determination of $V_{u d}$ from superallowed beta decays within a systematically improvable framework.
nucl-thhep-exhep-phnucl-exPRL(2025)·41 citations
04
Radiative corrections to superallowed $β$ decays in effective field theory
Vincenzo Cirigliano🇺🇸 · Wouter Dekens🇺🇸 · Jordy de Vries🇳🇱 · Stefano Gandolfi🇺🇸 · Martin Hoferichter🇨🇭 · Emanuele Mereghetti🇺🇸
The accuracy of $V_{u d}$ determinations from superallowed $β$ decays critically hinges on control over radiative corrections. Recently, substantial progress has been made on the single-nucleon, universal corrections, while nucleus-dependent effects, typically parameterized by a quantity $δ_{NS}$ , are much less well constrained. Here, we lay out a program to evaluate this correction from effective field theory (EFT), highlighting the dominant terms as predicted by the EFT power counting. Moreover, we compare the results to a dispersive representation of $δ_{NS}$ and show that the expected momentum scaling applies even in the case of low-lying intermediate states. Our EFT framework paves the way towards ab-initio calculations of $δ_{NS}$ and thereby addresses the dominant uncertainty in $V_{u d}$ .
↳ hep-phhep-exhep-latnucl-ex+1PRL(2024)·42 citations
05
Towards the understanding of heavy quarks hadronization: from leptonic to heavy-ion collisions
J. Altmann🇦🇺 · A. Dubla🇩🇪 · V. Greco🇮🇹 · A. Rossi🇮🇹 · P. Skands🇦🇺
The formation of hadrons is a fundamental process in nature that can be investigated at particle colliders. As several recent findings demonstrate, with $e^{+} e^{-}$ collisions as a "vacuum-like" reference at one extreme, and central nucleus--nucleus as a dense, extended-size system characterized by flow and local equilibrium at the opposite extreme, different collision systems offer a lever arm that can be exploited to probe with a range of heavy-flavour hadron species the onset of various hadronization processes. In this review, we present an overview of the theoretical and experimental developments. The focus is on open-heavy-flavour measurements. The comparison with model predictions and connections among the results in electron-positron, proton--proton, proton--nucleus, nucleus--nucleus collisions are discussed. After reviewing the current state, we suggest some prospects and future developments.
↳ hep-phnucl-exnucl-thEPJC(2025)·38 citations
06
Measuring differential particle correlations in relativistic nuclear collisions
Niseem Magdy🇺🇸
This study explores the transverse momentum ( $p_{T}$ ) dependencies of Symmetric and Asymmetric Correlations (SC and ASC) with one and two particles of interest in Au+Au collisions at 200 GeV. Leveraging the AMPT model, the investigation delves into the sensitivity of these correlations to the final state effects, providing valuable insights into their potential for constraining the final state effects' $p_{T}$ dependencies. The HIJING model is employed as a benchmark for non-flow correlations, shedding light on their impact on interpreting SC and ASC data. Moreover, the study points out that differential SC and ASC with one and two particles of interest (POIs) typically incorporate contributions from event-plane angle fluctuations. Consequently, this work highlights the significance of SC and ASC with one and two POIs as valuable tools for investigating the $p_{T}$ nature of the final state effects and advocates for comprehensive experimental measurements across various beam energies and system sizes to enhance our understanding and provide additional constraints for theoretical models.
↳ hep-phnucl-exnucl-thPRC(2024)·2 citations
07
Dark matter admixed neutron stars with a realistic nuclear equation of state from chiral nuclear interactions
Domenico Scordino🇮🇹 · Ignazio Bombaci🇮🇹
We study the effects of dark matter on the structural properties of neutron stars. In particular we investigate how the presence of a dark matter component influences the mass-radius relation, the value of the maximum mass of a neutron star and other stellar properties. To model ordinary matter we use a state-of-the-art equation of state of $β$ -stable nuclear matter obtained using the Brueckner-Hartree-Fock quantum many-body approach starting from two-body and three-body nuclear interactions derived from chiral effective field theory. The dark matter component of the star is modeled as a non-self-annihilating system of spin $1/2$ fermions at zero temperature and its equation of state as an ideal relativistic Fermi gas. The equilibrium configurations of these dark matter admixed neutron stars (DANS) are calculated by solving a generalization of the Tolman-Oppenheimer-Volkoff equations to the case where the system consists of two perfect fluids interacting solely through gravity. We find that, depending on the dark matter particle mass $m_{χ}$ , one can have somehow opposite effects on the stellar properties. In the case $m_{χ} = 1 GeV$ , the stellar gravitational maximum mass $M_{ma x}$ decreases, whereas in the case $m_{χ} = 0.1 GeV$ , $M_{ma x}$ increases with respect to the maximum mass of ordinary neutron stars. We also show that the presence of dark matter has indirect sizable effect on the proton fraction in the ordinary matter fluid and, in the case $m_{χ} = 1 GeV$ , results in a decrease of the threshold gravitational mass $M_{t o t}^{d u r c a}$ for having direct URCA processes and fast stellar cooling. Finally we study the stability of dark matter admixed neutron stars with respect to radial perturbations.
↳ astro-ph.HEgr-qcnucl-thJHEAp(2025)·17 citations

Affiliations

first authorsco-authorsvia INSPIRE

Ab-initio electroweak corrections to superallowed β decays and their impact on Vud​

Neutron skin impurity from Coulomb core polarization in 208Pb: Insights from PREX-II and validation via the (3He,t) isobaric analog state reaction

An ab initio strategy for taming nuclear-structure dependence of Vud​ extractions: the 10C→10B superallowed transition

Radiative corrections to superallowed β decays in effective field theory

Towards the understanding of heavy quarks hadronization: from leptonic to heavy-ion collisions

Measuring differential particle correlations in relativistic nuclear collisions

Dark matter admixed neutron stars with a realistic nuclear equation of state from chiral nuclear interactions

Affiliations

Ab-initio electroweak corrections to superallowed $β$ decays and their impact on $V_{u d}$

Neutron skin impurity from Coulomb core polarization in $^{208} Pb$ : Insights from PREX-II and validation via the $(^{3} He, t)$ isobaric analog state reaction

An $ab initio$ strategy for taming nuclear-structure dependence of $V_{u d}$ extractions: the $^{10} C \to^{10} B$ superallowed transition

Radiative corrections to superallowed $β$ decays in effective field theory