Wed·Jul 19, 2023Wednesday·July 19, 2023

1. 01*

   Computing Jet Transport Coefficients On The Lattice

   Amit Kumar🇨🇦 · Abhijit Majumder🇺🇸 · Ismail Soudi🇺🇸 · Johannes H. Weber🇩🇪

   The leading jet transport coefficients $\hat{q}$ or ${\hat{e}}_2$ encode transverse or longitudinal momentum broadening of a hard parton traversing a hot medium. Understanding their temperature dependence is key to appreciating the observed suppression of high-transverse momentum probes at RHIC or LHC collision energies. We present a first continuum extrapolated result of $\hat{q}$ computed on pure SU(3) lattices with non-trivial temperature dependence different from the weak-coupling expectation. We discuss our formalism and its challenges and status in view of obtaining ${\hat{e}}_2$ or of unquenching the calculation. We consider a hard quark subject to a single scattering on the plasma. The transport coefficients are factorized in terms of matrix elements given as integrals of non-local gauge-covariant gluon field-strength field-strength correlators. After the analytic continuation to the deep-Euclidean region, the hard scale permits to recast these as a series of local, gauge-invariant operators. The renormalized leading-twist term in this expansion is closely related to static quantities, and is computed on pure SU(3) lattices ($N_{\tau }=4,6,8,$ and $10$) for a wide range of temperatures, ranging from 200MeV < T < 1GeV. Our estimate for the unquenched result in $2+1$-flavor QCD has very similar features.

   ↳ hep-lathep-phnucl-exnucl-thPoS(2023)·1 citation
2. 02*

   A view of Coherent Elastic Neutrino-Nucleus Scattering

   M. Cadeddu🇮🇹 · F. Dordei🇮🇹 · C. Giunti🇮🇹

   We review the physics of coherent elastic neutrino-nucleus scattering and the results and perspectives for the measurements of the radius of the neutron distribution of the nucleus, of the weak mixing angle, and of new neutrino interactions due to physics beyond the Standard Model.

   ↳ hep-phhep-exnucl-exnucl-thEPL(2023)·34 citations
3. 03*

   Triple Charmonium Production in pQCD

   B. Blok🇮🇱 · J. Mehl (Technion)🇮🇱

   We study the role of $1\to 2$ and $1\to 3$ processes in triple charmonium production. We see that the ratio of effective cross sections of TPS and DPS only moderately depends on charmonium transverse momenta, but the total DPS and TPS cross sections each separately may have rather strong dependence on charmonia transverse momenta in the central kinematics that can be studied experimentally.

   ↳ hep-phhep-exnucl-exnucl-thEPJC(2024)·1 citation
4. 04*

   New estimation of the nuclear de-excitation line emission from the supernova remnant Cassiopeia A

   Bing Liu🇨🇳 · Rui-zhi Yang🇨🇳 · Xin-yu He · Felix Aharonian🇮🇪

   MeV nuclear de-excitation lines serve as a unique tool to study low-energy cosmic rays (CRs), containing both spectral and elemental information of the interacting material. In this paper, we estimated the possible nuclear de-excitation lines from the young supernova remnant Cassiopeia A. Given different CR spectral shapes and interacting materials, we found the predicted fluxes of strong narrow line emissions from the remnant are highly model-dependent, ranging from about $1\times 10^{-10}\mathrm{c}{\mathrm{m}}^{-2}{\mathrm{s}}^{-1}$ to $1\times 10^{-6}\mathrm{c}{\mathrm{m}}^{-2}{\mathrm{s}}^{-1}$ for the 4.44 MeV narrow line and from about $4\times 10^{-11}\mathrm{c}{\mathrm{m}}^{-2}{\mathrm{s}}^{-1}$ to $2\times 10^{-7}\mathrm{c}{\mathrm{m}}^{-2}{\mathrm{s}}^{-1}$ for the 6.13 MeV narrow line, respectively. Based on the new estimation, we also discussed the detection probability of these line emissions against the MeV diffuse Galactic background under different assumptions of instrument response functions.

   ↳ astro-ph.HEastro-ph.SRnucl-exMNRAS(2023)·7 citations
5. 05*

   Postfission properties of uranium isotopes: A hybrid method with Langevin dynamics and the Hauser-Feshbach statistical model

   Shyoya Tanaka🇯🇵 · Nobuya Nishimura🇯🇵 · Futoshi Minato🇯🇵 · Yoshihiro Aritomo🇯🇵

   Background: Precise understanding of nuclear fission is crucial for experimental and theoretical nuclear physics, astrophysics, and industrial applications; however, the complete physical mechanics is unresolved due to the complexities. Purpose: In this study, we present a new method to describe the dynamical-fission process and following prompt-neutron emission, where we combine the dynamical fission calculation based on the Langevin method and the Hauser-Feshbach statistical model. Methods: Two methods are connected smoothly within the universal charge distribution and the energy conservation, allowing us to calculate a sequence of fission dynamics and post-fission phase, including prompt neutron emission. Results: Using a certain set of model parameters, we successfully reproduce the experimental primary-fission yields, total kinetic energy, independent-fission yields, and prompt neutron emissions for the neutron induced fission of ${}^{236}$U, a compound nucleus of $\mathrm{n}+{}^{235}\mathrm{U}$. We elucidate the physical mechanism of the characteristic features observed in previous experiments, such as shell properties. Additionally, we apply our calculation to two very neutron-rich uranium isotopes, i.e., ${}^{250}$U and ${}^{255}$U, which are not experimentally confirmed but are important for r-process nucleosynthesis. Theoretical results indicate that ${}^{250}$U exhibits an asymmetric multiple-peak fission yield distribution, while the neutron-rich ${}^{255}$U has a single peak due to symmetric fission. Our method predicts post-neutron emission fragments, where ${}^{250}$U shows a stronger neutron emissivity than ${}^{255}$U. Conclusions: Our framework is highly reproducible in the experiments and shows that the number of emitted neutrons after fission differs significantly in neutron-rich uranium fission depending on distributions of fission variables.

   ↳ nucl-thastro-ph.HEnucl-exPRC(2023)·5 citations
6. 06*

   Drag force near the QCD critical point

   Yukinao Akamatsu🇯🇵 · Masayuki Asakawa🇯🇵

   We discuss how heavy quark dynamics is affected by the critical fluctuations near the QCD critical point at finite temperature and density. We find that the heavy quark momentum diffusion constant scales as $\kappa \propto {\xi }^{z-3-\eta }$. In the model H scenario, which is widely accepted for the critical dynamics, the exponents are known as $z\simeq 3,\eta \sim 0.04$ and the critical singularity of $\kappa$ is not significant if any. In the model B scenario, $z\simeq 4$ and $\kappa \propto \xi$ is singular near the critical point.

   ↳ nucl-thcond-mat.quant-gashep-phnucl-exPRC(2024)·1 citation
7. 07*

   All-optical Differential Radii in Zinc

   B. K. Sahoo🇮🇳 · B. Ohayon🇮🇱

   We conduct high-accuracy calculations of isotope shift (IS) factors of the states involving the $D_1$ and $D_2$ lines in Zn II. Together with a global fit to the available optical IS data, we extract nuclear-model-independent, precise differential radii for a long chain of Zn isotopes. These radii are compared with the ones inferred from muonic X-ray measurements. Some deviations are found, which we ascribe to the deformed nature of Zn nuclei that introduces nuclear-model dependency into radii extractions from muonic atoms. We arrive at the conclusion that in cases where the many-body atomic calculations of IS factors are well-established, optical determinations of differential radii are more reliable than those extracted from the muonic X-ray measurements, opening the door to improved determination of nuclear radii across the nuclear chart.

   ↳ physics.atom-phnucl-exPRResearch(2023)·8 citations
8. 08*

   Theoretical study on ${\Lambda }_c^{+}\to \Lambda K^{+}{\bar{K}}^0$ decay and ${\Xi }^{\ast }(1690)$ resonance

   Si-Wei Liu🇨🇳 · Qing-Hua Shen🇨🇳 · Ju-Jun Xie🇨🇳

   We present a theoretical study of ${\Xi }^{\ast }(1690)$ resonance in the ${\Lambda }_c^{+}\to \Lambda K^{+}{\bar{K}}^0$ decay, where the weak interaction part proceeds through the Cabibbo-favored process $c\to s+u\bar{d}$. Next, the intermediate two mesons and one baryon state can be constructed with a pair of $q\bar{q}$ with the vacuum quantum numbers. Finally, the ${\Xi }^{\ast }(1690)$ is mainly produced from the final state interactions of $\bar{K}\Lambda$ in coupled channels, and it is shown in the $\bar{K}\Lambda$ invariant mass distribution. Besides, the scalar meson $a_0(980)$ and nucleon excited state $N^{\ast }(1535)$ are also taken into account in the decaying channels $K^{+}{\bar{K}}^0$ and $K^{+}\Lambda$, respectively. Within model parameters, the $K^{+}{\bar{K}}^0$, ${\bar{K}}^0\Lambda$ and $K^{+}\Lambda$ invariant mass distributions are calculated, and it is found that our theoretical results can reproduce well the experimental measurements, especially for the clear peak around $1690$ MeV in the $\bar{K}\Lambda$ spectrum. The proposed weak decay process ${\Lambda }_c^{+}\to \Lambda K^{+}{\bar{K}}^0$ and the interaction mechanism can provide valuable information on the nature of the ${\Xi }^{\ast }(1690)$ resonance.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2023)·12 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.