Nuclear Theory·nucl-th

Tuesday·November 5, 2024

19 papers—9 primary·10 cross-listed

01
[Submitted on 31 Oct 2024]
Role of Lambda N and Lambda NN interaction parameters on binding energy of Lambda H4 and Lambda H4*
Bhupali Sharma🇮🇳
Variational Monte Carlo study has been done for the two hypernuclear systems $_{Λ}^{4}$ H and $_{Λ}^{4}$ H $^{*}$ for calculation of binding energies. For the two hypernuclear systems under study, different potential models have been used for the interactions involved in these hypernuclear systems. ArgonneV $_{18}$ NN, Urbana IX NNN and phenomenological $Λ$ N and $Λ$ NN potentials have been used in our study. Our potential models are based on our previous studies on different double lambda hypernuclear systems. From our results, hyperon-nucleon parameters ie. two-body $Λ$ N parameter and three-body $Λ$ NN parameters are found to be important for binding the hypernuclear systems under study. With reduction in the values of Lambda NN interaction parameters used in earlier works , there is significant difference in the values of binding energy of $_{Λ}^{4}$ H and $_{Λ}^{4}$ H $^{*}$ . Also, $Λ$ N interaction parameters are also found to play important role in binding.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2411.00880 [pdf]
Journal of Applied and Fundamental Scienc…·0 citations
02
[Submitted on 31 Oct 2024]
Variational study of s-shell lambda hypernuclear system
Bhupali Sharma🇮🇳
Theoretical study on hypernuclear systems is important to know the nature of hyperon-nucleon and hyperon-hyperon interaction as only hypernuclear systems give the scope of knowing these interactions. A hypernucleus, in addition to the nucleons contains at least one hyperon which is a strange particle composed of quarks. A hypernucleus is produced mostly in heavy ion collisions and it undergoes weak decay. Experimental detection of hypernuclear events are rare and this makes the study of hypernuclear physics more challenging. Hypernuclear physics has a close association with astrophysics as hyperon-nucleon and hyperon-hyperon interactions are found to play important role in the interiors of neutron stars. The core of neutron stars contains strange quark matter and therefore, study of hyperon involved potentials are essential for the determination of the composition of neutron star matter. But, there is a scarcity of data from hyperon-nucleon scattering experiments. Also, since it is impossibe to have hyperon-hyperon scattering experiments, the direct determination of the baryon-baryon interaction strength is extremely difficult. Therefore theoretical models play important role in unfolding the mysteries of hyperon-nucleon and hyperon-hyperon interaction. In this study, binding energies of hypernuclear systems calculated using different two-body lambda-nucleon and three-body lambda-nucleon-nucleon interactions have been analysed. Also effect of lambda-lambda potential on the binding energy of hypernuclear system have been analysed. In this few-body study, we have employed Variational Monte Carlo technique for calculation of the binding energies of different hyperclear systems.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2411.00884 [pdf]
Journal of Applied and Fundamental Scienc…·0 citations
03
[Submitted on 2 Nov 2024]
Role of octupole shape degree of freedom in neutron-rich odd-mass xenon isotopes
K. Nomura
Influences of the octupole shape degree of freedom on low-energy spectra of neutron-rich odd-mass xenon isotopes are studied within the interacting boson-fermion model that is based on the nuclear density functional theory. The interacting-boson Hamiltonian describing low-energy quadrupole and octupole collective states of the even-even nuclei $^{140, 142, 144}$ Xe, single-particle energies, and occupation probabilities for an unpaired neutron in the odd-mass nuclei $^{141, 143, 145}$ Xe, are determined based on the axially symmetric quadrupole-octupole deformation-constrained self-consistent mean-field calculations with a choice of the energy density functional and pairing interaction. Strength parameters of the boson-fermion interactions are empirically determined to reproduce a few low-lying levels of each odd-mass nucleus. The mean-field calculation predicts for $^{142}$ Xe a potential energy surface that is notably soft in the octupole deformation with a non-zero octupole global minimum. The octupole correlations are shown to be relevant in positive-parity excited states of $^{143, 145}$ Xe.
Comments:
13 pages, 9 figures, 9 tables
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2411.01262 [pdf]
PRC(2024)·4 citations
04
[Submitted on 2 Nov 2024]
Quark jet evolution: from classical to quantum simulation
Meijian Li🇪🇸
Quark jet provides one of the best ways to probe the matter produced in ultrarelativistic high-energy collisions, from cold nuclear matter to the hot quark-gluon plasma. In this proceeding paper, we review a series of works on the development of nonperturbative computational framework of in-medium quark jet evolution, from classical to quantum simulation. The application of the time-dependent Basis Light-front Quantization (tBLFQ), a nonperturbative computational approach based on light-front Hamiltonian formalism, to in-medium jet evolution enables a fully quantum treatment to the jet state on the amplitude level. Based on the tBLFQ framework, with applying novel quantum technologies, we have constructed a digital quantum circuit that tracks the evolution of a multi-particle jet probe within a stochastic color background field. With the obtained simulation results, we extracted the medium induced modification in terms of jet momentum broadening and gluon production. These studies provide a baseline for future works of in-medium jet evolution using quantum computers.
Comments:
Proceeding of LHCP 2024
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Quantum Physics (quant-ph)
arXiv:
2411.01318 [pdf]
PoS(2025)·3 citations
05
[Submitted on 3 Nov 2024]
Shannon entropy of optimized proton-neutron pair condensates
Shu-Yuan Liang · Yi Lu · Yang Lei · Calvin W. Johnson · Guan-Jian Fu · Jia Jie Shen
Proton-neutron pairing and like-nucleon pairing are two different facets of atomic nuclear configurations. While like-nucleon pair condensates manifest their superfluidic nature in semi magic nuclei, it is not absolutely clear if there exists a T=0 proton-neutron pair condensate phase in $N = Z$ nuclei. With an explicit formalism of general pair condensates with good particle numbers, we optimize proton-neutron pair condensates for all $N = Z$ nuclei between $^{16}$ O and $^{100}$ Sn, given shell model effective interactions. As comparison, we also optimize like-nucleon pair condensates for their semi-magic isotones. Shannon entanglement entropy is a measurement of mixing among pair configurations, and can signal intrinsic phase transition. It turns out the like-nucleon pair condensates for semi-magic nuclei have large entropies signaling an entangled phase, but the proton-neutron pair condensates end up not far from a Hartree-Fock solution, with small entropy. With artificial pairing interaction strengths, we show that the general proton-neutron pair condensate can transit from an entangled T=1 phase to an entangled T=0 phase, i.e. pairing phase transition driven by external parameters. In the T=0 limit, the proton-neutron pair condensate optimized for $^{24}$ Mg turns out to be a purely P pair condensate with large entanglement entropy, although such cases may occur in cold atom systems, unlikely in atomic nuclei.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2411.01439 [pdf]
PRC(2025)·9 citations
06
[Submitted on 3 Nov 2024]
Transitions To Door-way States And Nuclear Responses Against 2-body External Fields
Futoshi Minato
Nuclear microscopic structural models that treat two-body effective interactions self-consistently becomes available, one of which is second-random-phase-approximation (SRPA). SRPA can be used to study evolutions from 1 particle-1 hole (1p1h) to 2 particle-2 hole (2p2h) states from different point of view from reaction models. We studied nuclear excitations created by 1-body and 2-body external fields and discuss transitions between 1p1h and 2p2h states obtained by the SRPA approach.
Comments:
5 pages, 8 figures, proceedings for CNR*24
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2411.01709 [pdf]
EPJ Web Conf.(2025)·0 citations
07
[Submitted on 3 Nov 2024]
The role of intermediate $ΔΔ$ states in nucleon-nucleon scattering in the large- $N_{c}$ and unitary limits, and $ΔΔ$ and $ΩΩ$ scattering
Thomas R. Richardson🇺🇸 · Matthias R. Schindler🇺🇸 · Roxanne P. Springer🇺🇸
We explore potential explanations for why using large- $N_{c}$ ( $N_{c}$ is the number of colors) scaling to determine the relative size of few-nucleon low-energy operators agrees with experiment even when dynamical $Δ$ 's are not explicitly included. Given that the large- $N_{c}$ analysis is predicated on the nucleons and $Δ$ 's being degenerate, this is a curious result. We show that for purely $S$ -wave interactions the relationships dictated by large- $N_{c}$ scaling are unaffected whether the $Δ$ is included or not. In the case of higher partial waves that do not mix with $S$ -waves, the impact of the $Δ$ is perturbative, which makes the agreement with naive ( $Δ$ -less) large- $N_{c}$ ordering unsurprising. For higher partial waves that mix with $S$ -waves, the nucleon and $Δ$ would need to decouple to get agreement with naive large- $N_{c}$ ordering. We find all $N N$ , $Δ N$ , and $ΔΔ$ low energy coefficients for leading-order baryon-baryon scattering in $Δ$ -full pionless effective field theory in terms of the two independent parameters dictated by the SU( $2 F$ ) spin-flavor symmetry that arises in the $N_{c} \to \infty$ limit. Because of recent lattice QCD results and experimental interest, we extend our analysis to the three-flavor case to study $ΩΩ$ scattering. We show that in the unitary limit (where scattering lengths become infinite) one of the two SU( $2 F$ ) parameters is driven to zero, resulting in enhanced symmetries, which agree with those found in spin-1/2 entanglement studies.
Comments:
33 pages, two figures, version accepted for publication in Journal of Physics G
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2411.01715 [pdf]
J.Phys.G(2025)·5 citations
08
[Submitted on 4 Nov 2024]
Investigation of entanglement in $N = Z$ nuclei within no-core shell model
Chandan Sarma · Praveen C. Srivastava
In this work, we explore the entanglement structure of two $N = Z$ nuclei, $^{20}$ Ne and $^{22}$ Na using single-orbital entanglement entropy within the No-Core Shell Model (NCSM) framework for two realistic interactions, INOY and N $^{3}$ LO. We begin with the determination of the optimal frequencies based on the variation of ground-state (g.s.) binding energy with NCSM parameters, $N_{ma x}$ and $ℏΩ$ , followed by an analysis of the total single-orbital entanglement entropy, $S_{t o t}$ , for the g.s. of $^{20}$ Ne and $^{22}$ Na. Our results show that $S_{t o t}$ increases with $N_{ma x}$ and decreases with $ℏΩ$ after reaching a maximum. We use $S_{t o t}$ to guide the selection of an additional set of optimal frequencies that can enhance electromagnetic transition strengths. We also calculate the low-energy spectra and $S_{t o t}$ for four low-lying states of $^{20}$ Ne and six low-lying states of $^{22}$ Na. Finally, we calculate a few $E 2$ and one $M 1$ transition strengths, finding that N $^{3}$ LO provides better results for $B (E 2; 5_{1}^{+} \to 3_{1}^{+}$ ) and INOY performs well for the $B (M 1; 0_{1}^{+} \to 1_{1}^{+})$ transition in the $^{22}$ Na nucleus while considering the first set of optimal frequencies. We also observe that the second set of optimal frequencies enhances electromagnetic transition strengths, particularly for the states with large and comparable $S_{t o t}$ . Also, for both nuclei, the $S_{t o t}$ for INOY and N $^{3}$ LO are close while considering the second set of optimal frequencies, suggesting that the calculated $S_{t o t}$ are more dependent on $ℏΩ$ than the interactions employed for the same model space defined by the $N_{ma x}$ parameter.
Comments:
15 pages, 5 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2411.01861 [pdf]
NPA(2026)·4 citations
09
[Submitted on 4 Nov 2024]
Folding procedure for $Ω$ - $α$ potential
Igor Filikhin🇺🇸 · Roman Ya. Kezerashvili🇺🇸 · Branislav Vlahovic🇺🇸
Using the folding procedure, we investigate the bound state of the $Ω$ + $α$ system based on $Ω$ - $N$ ( $^{5} S_{2}$ ) HAL QCD potential. Previous theoretical analyses have indicated the existence of a deeply bound ground state, which is attributed to the strong $Ω$ -nucleon interaction. By employing well-established parameterizations of nucleon density within the alpha particle, and the central HAL QCD $Ω$ - $N$ potential, we performed numerical calculations for the folding $Ω$ - $α$ potential. Our results show that the $V_{Ω α} (r)$ potential can be accurately fitted using a Woods-Saxon function, with a phenomenological parameter $R = 1.1 A^{1/3} \approx 1.74$ fm ( $A = 4$ ) in the asymptotic region where $2 < r < 3$ fm. We provide a thorough description of the corresponding numerical procedure. Our evaluation of the binding energy of the $Ω$ + $α$ system within the cluster model is consistent with both previous and recent reported findings. To further validate the folding procedure, we also calculated the $Ξ$ - $α$ folding potential based on a simulation of the ESC08c $Y$ - $N$ Nijmegen model. A comprehensive comparison between the $Ξ$ - $α$ folding and $Ξ$ - $α$ phenomenological potentials is presented and discussed.
Comments:
9 pages, 3 Figures
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Lattice (hep-lat)
arXiv:
2411.02021 [pdf]
Few Body Syst.(2025)·7 citations
10
[Submitted on 1 Nov 2024] (cross-list from math.AP)
The linearized Israel-Stewart equations with a physical vacuum boundary
Runzhang Zhong
In this article, we consider the Israel-Stewart equations of relativistic viscous fluid dynamics with bulk viscosity. We investigate the evolution of the equations linearized about solutions that satisfy the physical vacuum boundary condition and establish local well-posedness of the corresponding Cauchy problem.
Subjects:
math.AP (math.AP); Nuclear Theory (nucl-th)
arXiv:
2411.00291 [pdf]
Lett.Math.Phys.(2025)·0 citations
11
[Submitted on 1 Nov 2024] (cross-list from gr-qc)
Masking equation of state effects in binary neutron star mergers
Antonios Tsokaros🇺🇸 · Jamie Bamber🇺🇸 · Milton Ruiz🇪🇸 · Stuart L. Shapiro🇺🇸
Recent nonmagnetized studies of binary neutron star mergers have indicated the possibility of identifying equation of state features, such as a phase transition or a quark-hadron crossover, based on the frequency shift of the main peak in the postmerger gravitational wave spectrum. By performing a series of general relativistic, magnetohydrodynamic simulations we show that similar frequency shifts can be obtained due to the effect of the magnetic field. The existing degeneracy can either mask or nullify a shift due to a specific equation of state feature, and therefore the interpretation of observational data is more complicated than previously thought, requiring a more complete treatment that would necessarily include the neutron star's magnetic field.
Comments:
6 pages, 4 figures
Subjects:
General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2411.00939 [pdf]
PRL(2025)·16 citations
12
[Submitted on 1 Nov 2024] (cross-list from gr-qc)
Postmerger multimessenger analysis of binary neutron stars: Effect of the magnetic field strength and topology
Jamie Bamber🇺🇸 · Antonios Tsokaros🇺🇸 · Milton Ruiz🇪🇸 · Stuart L. Shapiro🇺🇸
The oscillation modes of neutron star (NS) merger remnants, as encoded by the kHz postmerger gravitational wave (GW) signal, hold great potential for constraining the as-yet undetermined equation of state (EOS) of dense nuclear matter. Previous works have used numerical relativity simulations to derive quasi-universal relations for the key oscillation frequencies, but most of them omit the effects of a magnetic field. We conduct full general-relativistic magnetohydrodynamics simulations of NSNS mergers with two different masses and two different EOSs (SLy and ALF2) with three different initial magnetic field topologies (poloidal and toroidal only, confined to the interior, and "pulsar-like": dipolar poloidal extending from the interior to the exterior), with four different magnetic field strengths with maximum values ranging from from $5.5 \times 1 0^{15} G$ to $2.2 \times 1 0^{17} G$ at the time of insertion. We find that magnetic braking and magnetic effective turbulent viscosity drives the merger remnants towards uniform rotation and increases their overall angular momentum loss. As a result, the $f_{2}$ frequency of the dominant postmerger GW mode shifts upwards over time. The overall shift is up to $\sim 200$ Hz for the strongest magnetic field we consider and $\sim 50$ Hz for the median case and is therefore detectable in principle by future GW observatories, which should include the magnetic field in their analyses. We also explore the impact of the magnetic field on the postmerger electromagnetic emission, and demonstrate that an extremely large magnetic field, or alternatively a significant shear viscosity mechanism, can cause a supramassive NS remnant to collapse to a BH in less than 100ms and lead to jet formation, although we do not expect the conditions for such an outcome to be realistic.
Comments:
33 pages, 22 figures. arXiv admin note: text overlap with arXiv:2405.03705
Subjects:
General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2411.00943 [pdf]
PRD(2025)·21 citations
13
[Submitted on 1 Nov 2024] (cross-list from hep-lat)
Adiabatic state preparation for digital quantum simulations of QED in 1 + 1D
Matteo D'Anna🇨🇭 · Marina Krstic Marinkovic🇨🇭 · Joao C. Pinto Barros🇨🇭
Quantum electrodynamics in 1 + 1D (QED2) shares intriguing properties with QCD, including confinement, string breaking, and interesting phase diagram when the non-trivial topological $θ$ -term is considered. Its lattice regularization is a commonly used toy model for quantum simulations of gauge theories on near-term quantum devices. In this work, we address algorithms for adiabatic state preparation in digital quantum simulations of QED2. We demonstrate that, for specific choices of parameters, the existing adiabatic procedure leads to level crossing between states of different charge sectors, preventing the correct preparation of the ground state. We further propose a new adiabatic Hamiltonian and verify its efficiency in targeting systems with a nonzero topological $θ$ -term and in studying string breaking phenomena.
Comments:
12 pages, 5 figures
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th); Quantum Physics (quant-ph)
arXiv:
2411.01079 [pdf]
PRD(2025)·11 citations
14
[Submitted on 2 Nov 2024] (cross-list from nucl-ex)
Proton induced reaction on $^{108}$ Cd for astrophysical p-process studies
Sukhendu Saha · Dipali Basak · Tanmoy Bar · Lalit Kumar Sahoo · Jagannath Datta · Sandipan Dasgupta · Norikazu Kinoshita · Chinmay Basu
The proton capture cross-section of the least abundant proton-rich stable isotope of cadmium, $^{108}$ Cd (abundance 0.89\%), has been measured near the Gamow window corresponding to a temperature range of 3-4 GK. The measurement of the $^{108}$ Cd(p, $γ$ ) $^{109}$ In reaction was carried out using the activation technique. The cross-section at the lowest energy point of 3T $_{9}$ , E $_{p}$ $^{l ab}$ = 2.28 MeV, has been reported for the first time. The astrophysical S-factor was measured in the energy range relevant to the astrophysical p-process, between E $_{p}$ $^{c m}$ = 2.29 and 6.79 MeV. The experimental results have been compared with theoretical predictions of Hauser-Feshbach statistical model calculations using TALYS-1.96. A calculated proton-optical potential was implemented to achieve better fitting, with different combinations of available nuclear level densities (NLDs) and $γ$ -ray strength functions in TALYS-1.96. The calculations provided satisfactory agreement with the experimental results. The reaction rate was calculated using the calculated potential in TALYS-1.96 and compared with the values provided in the REACLIB database.
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2411.01279 [pdf]
J.Phys.G(2025)·5 citations
15
[Submitted on 3 Nov 2024] (cross-list from astro-ph.SR)
Impact of the Brink Axel Hypothesis on Unique First Forbidden \b{eta} transitions for r process nuclei
Fakeha Farooq · Jameel-Un Nabi · Ramoona Shehzadi
Key nuclear inputs for the astrophysical r process simulations are the weak interaction rates. Consequently, the accuracy of these inputs directly affects the reliability of nucleosynthesis modeling. Majority of the stellar rates, used in simulation studies, are calculated invoking the Brink Axel (BA) hypothesis. The BA hypothesis assumes that the strength functions of all parent excited states are the same as for the ground state, only shifted in energies. However, BA hypothesis has to be tested against microscopically calculated state by state rates. In this project we study the impact of the BA hypothesis on calculated stellar \b{eta} decay and electron capture rates. Our investigation include both Unique First Forbidden (U1F) and allowed transitions for 106 neutron rich trans iron nuclei ([27, 77] less than equal to [Z, A] less than equal to [82, 208]). The calculations were performed using the deformed proton-neutron quasiparticle randomphase approximation (pn QRPA) model with a simple plus quadrupole separable and schematic interaction. Waiting-point and several key r process nuclei lie within the considered mass region of the nuclear chart.
Comments:
33 pages, 6 Tables, 8 Figures
Subjects:
Solar and Stellar Astrophysics (astro-ph.SR); Nuclear Theory (nucl-th)
arXiv:
2411.01436 [pdf]
CPC(2024)·1 citation
16
[Submitted on 3 Nov 2024] (cross-list from astro-ph.SR)
Radiative Capture of proton 14N(p,{\gamma}) 15O at Low Energy
B.F. Irgaziev · Abdul Kabir · Jameel-Un Nabi
The CNO cycle is the main source of energy in stars more massive than our Sun. It defines the energy production and the duration contributes in determining the lifetime of massive stars. The cycle is an important tool for the determination of the age of globular clusters. Radiative capture p plus 14N 15O plus {\gamma}, at energies of astrophysical interest, is one of the important processes in the CNO cycle. In this project, we apply a potential model to describe both non resonant and resonant reactions in the channels where radiative capture occurs through electric E1 transitions. We employed the R matrix method to describe the reactions going via M1 resonant transitions, when it was not possible to correctly reproduce the experimental data by a potential model. The partial components of the astrophysical S factor are calculated for all possible electric and magnetic dipole transitions in 15O. The linear extrapolated S factor at zero energy (S(0)) is in good agreement with earlier reported values for all types of transitions considered in this work. Based on the value of the total astrophysical S factor, depending on the collision energy, we calculate the nuclear reaction rates for p plus 14N 15O plus {\gamma}. The computed rates are in good agreement with the results of the NACRE II Collaboration and the most recent existing measurements.
Comments:
11Pages, 8 figures, 6 Tables
Subjects:
Solar and Stellar Astrophysics (astro-ph.SR); Nuclear Theory (nucl-th)
arXiv:
2411.01444 [pdf]
CPC(2024)·3 citations
17
[Submitted on 4 Nov 2024] (cross-list from hep-ph)
Enhancing Bayesian parameter estimation by adapting to multiple energy scales in RHIC and LHC heavy-ion collisions
Maxim Virta🇫🇮 · Jasper Parkkila🇵🇱 · Dong Jo Kim🇫🇮
Improved constraints on current model parameters in a heavy-ion collision model are established using the latest measurements from three distinct collision systems. Various observables are utilized from Au--Au collisions at $s_{NN} = 200$ ~GeV and Pb--Pb collisions at $s_{NN} = 5.02$ ~TeV and $s_{NN} = 2.76$ ~TeV. Additionally, the calibration of centrality is now carried out separately for all parametrizations. The inclusion of an Au--Au collision system with an order of magnitude lower beam energy, along with separate centrality calibration, suggests a preference for smaller values of nucleon width, minimum volume per nucleon, and free-streaming time. The results with the acquired \textit{maximum a posteriori} parameters show improved agreement with the data for the second-order flow coefficient, identified particle yields, and mean transverse momenta. This work contributes to a more comprehensive understanding of heavy-ion collision dynamics and sets the stage for future improvements in theoretical modeling and experimental measurements.
Comments:
17 pages, 19 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2411.01932 [pdf]
PRC(2025)·11 citations
18
[Submitted on 4 Nov 2024] (cross-list from hep-ph)
Radially excited pion: electromagnetic form factor and the box contribution to the muon's $g - 2$
Angel S. Miramontes🇪🇸 · K. Raya🇪🇸 · A. Bashir🇲🇽 · P. Roig🇪🇸 · G. Paredes-Torres🇲🇽
We investigate the properties of the radially excited charged pion, with a specific focus on its electromagnetic form factor (EFF) and its box contribution to the hadronic light-by-light (HLbL) component of the muon's anomalous magnetic moment, $a_{μ}$ . Utilizing a coupled non-perturbative framework combining Schwinger-Dyson and Bethe-Salpeter equations, we first compute the mass and weak decay constant of the pion's first radial excitation. Initial results are provided for the Rainbow-Ladder (RL) approximation, followed by an extended beyond RL (BRL) analysis that incorporates meson cloud effects. Building on our previous work, this analysis demonstrates that an accurate description of the first radial excitation can be achieved without the need for a reparametrization of the interaction kernels. Having demonstrated the effectiveness of the truncation scheme, we proceed to calculate the corresponding EFF, from which we derive the contribution of the pion's first radial excitation to the HLbL component of the muon's anomalous magnetic moment, producing $a_{μ}^{π_{1} - box} (RL) = - (2.03 \pm 0.12) \times 1 0^{- 13}$ , $a_{μ}^{π_{1} - box} (BRL) = - (2.02 \pm 0.10) \times 1 0^{- 13}$ . Our computation also sets the groundwork for calculating related pole contributions of excited pseudoscalar mesons to $a_{μ}$ .
Comments:
12 pages, 3 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2411.02218 [pdf]
CPC(2025)·14 citations
19
[Submitted on 4 Nov 2024] (cross-list from hep-ph)
New Tool to Detect Inhomogeneous Chiral Symmetry Breaking
Theo F. Motta🇩🇪 · Julian Bernhardt🇩🇪 · Michael Buballa🇩🇪 · Christian S. Fischer🇩🇪
In this letter, we discuss a novel method to search for inhomogeneous chiral symmetry breaking in theories with fermions. The prime application we have in mind is QCD, but the method is also applicable for other theories, including solid-state applications. It is based on an extension of the chiral susceptibility to inhomogeneous phases and it works as a stability analysis. Our method allows us to determine when homogeneous solutions have the tendency to create spatially modulated condensates. As proof of principle, we apply this technique to a rainbow-ladder QCD model and find that its phase diagram contains an inhomogeneous region.
Comments:
Results extended to lower temperatures and larger chemical potentials. Extended results confirm the power of the new method and show definite signs of inhomogeneous chiral-SB
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2411.02285 [pdf]
PRD(2025)·18 citations

Affiliations

first authorsco-authorsvia INSPIRE