Tue·Aug 8, 2023Tuesday·August 8, 2023

1. 01*

   Efficient production of nuclear isomer ${}^{93m}$Mo with laser-accelerated proton beam and an astrophysical implication on ${}^{92m}$Mo production

   Wenru Fan🇺🇸 · Wei Qi · Jingli Zhang🇨🇳 · Zongwei Cao · Haoyang Lan🇨🇳 · Xinxiang Li🇨🇳 · Yi Xu🇨🇳 · Yuqiu Gu🇨🇳 · Zhigang Deng🇨🇳 · Zhimeng Zhang🇫🇷 · Changxiang Tan · Wen Luo🇨🇳 · Yun Yuan🇨🇳 · Weimin Zhou🇨🇳

   Nuclear isomers play a key role in the creation of the elements in the universe and have a number of fascinating potential applications related to the controlled release of nuclear energy on demand. Particularly, ${}^{93m}$Mo isomer is a good candidate for studying the depletion of nuclear isomer via nuclear excitation by electron capture. For such purposes, efficient approach for ${}^{93m}$Mo production needs to be explored. In the present work, we demonstrate experimentally an efficient production of ${}^{93m}$Mo through ${}^{93}$Nb(p, n) reaction induced by intense laser pulse. When a ps-duration, 100-J laser pulse is employed, the ${}^{93m}$Mo isomer at 2425 keV (21/2${}^{+}$, $T_{1/2}$ = 6.85 h) are generated with a high yield of $1.8\times 10^6$ particles/shot. The resulting peak efficiency is expected to be $10^{17}$ particles/s, which is at least five orders of magnitudes higher than using classical proton accelerator. The effects of production and destruction of ${}^{93m}$Mo on the controversial astrophysical p-isotope ${}^{92}$Mo are studied. It is found that the ${}^{93}$Nb(p, n)-${}^{93m}$Mo reaction is an important production path for ^{93m}Mo seed nucleus, and the influence of ^{93m}Mo-^{92}Mo reaction flow on ^{92}Mo production cannot be ignored. In addition, we propose to directly measure the astrophysical rate of (p, n) reaction using laser-induced proton beam since the latter one fits the Maxwell-Boltzmann distribution well. We conclude that laser-induced proton beam opens a new path to produce nuclear isomers with high peak efficiency towards the understanding of p-nuclei nucleosythesis.

   nucl-exastro-ph.SRnucl-thphysics.plasm-phPRResearch(2023)·5 citations
2. 02*

   A multistage framework for studying the evolution of jets and high-$p_T$ probes in small collision systems

   Abhijit Majumder · Aaron Angerami · Ritu Arora · Steffen Bass · Shanshan Cao · Yi Chen · Raymond Ehlers · Hannah Elfner · Wenkai Fan · Rainer J. Fries · Charles Gale · Yayun He and 39 other authors

   Understanding the modification of jets and high-$p_T$ probes in small systems requires the integration of soft and hard physics. We present recent developments in extending the JETSCAPE framework to build an event generator, which includes correlations between soft and hard partons, to study jet observables in small systems. The multi-scale physics of the collision is separated into different stages. Hard scatterings are first sampled at binary collision positions provided by the Glauber geometry. They are then propagated backward in space-time following an initial-state shower to obtain the initiating partons' energies and momenta before the collision. These energies and momenta are then subtracted from the incoming colliding nucleons for soft-particle production, modeled by the 3D-Glauber + hydrodynamics + hadronic transport framework. This new hybrid approach (X-SCAPE) includes non-trivial correlations between jet and soft particle productions in small systems. We calibrate this framework with the final state hadrons' $p_T$-spectra from low to high $p_T$ in $p$-$p$, and and then compare with the spectra in $p$-$Pb$ collisions from the LHC. We also present results for additional observables such as the distributions of event activity as a function of the hardest jet $p_T$ in forward and mid-rapidity for both $p$-$p$ and $p$-$Pb$ collisions.

   ↳ hep-phnucl-exnucl-thPoS(2024)·2 citations
3. 03*

   Cluster radioactivity from trans-tin to superheavy region using an improved empirical formula

   G. Saxena · A. Jain

   A simple relation $(a{Z}_c+b)(Z_d/Q{)}^{1/2}+(c{Z}_c+d)$ of estimation of the half-life of cluster emission is further improved for cluster and $\alpha$-decays, separately, by incorporating isospin of parent nucleus as well as angular momentum taken away by the emitted particle. This improved version is not only found robust in producing experimental half-lives belonging to the trans-tin and trans-lead regions but also elucidates cluster emission in superheavy nuclei over the usual $\alpha$-decay. Considering daughter nuclei around the doubly magic ${}^{100}$Sn and ${}^{208}$Pb nuclei for trans-tin and trans-lead (including superheavy) parents, respectively, a systematic and extensive study of 56$\le$Z$\le$120 isotopes is performed for the light and heavy cluster emissions. A fair competition among cluster emission, $\alpha$-decay, spontaneous fission, and $\beta$-decay is observed in this broad range resulting in a substantial probability of C to Sr clusters from several nuclei, which demonstrates the adequacy of shell effects. The present article proposes a single, improved, latest-fitted, and effective formula of cluster radioactivity that can be used to estimate precise half-lives for a wide range of the periodic chart from trans-tin to superheavy nuclei.

   ↳ nucl-thnucl-exEPJA(2023)·12 citations
4. 04*

   Probing the QCD phase transition with chiral mixing in dilepton production

   Azumi Sakai🇯🇵 · Masayasu Harada🇯🇵 · Chiho Nonaka🇯🇵 · Chihiro Sasaki🇵🇱 · Kenta Shigaki🇯🇵 · Satoshi Yano🇯🇵

   We perform a systematic study of dilepton emission in a hot QCD medium based on three different scenarios of chiral mixing, each of which yields a characteristic structure in the vector spectral function. The in-medium spectral functions are accommodated into the state-of-the-art hydrodynamic simulations for a relativistic viscous fluid to calculate the dilepton production rate, fully accounting for the space-time evolution of a created fireball in relativistic heavy-ion collisions. We demonstrate that the low-temperature theorem of chiral mixing extrapolated toward a chiral crossover, often used in the literature, leads to critical shortcomings: the inadequacy of width broadening, and a substantial overestimate of the dilepton yield maximized around the invariant mass of $M=1.2$ GeV. The proper prescription offers a milder yet sizable increase in the window of $1.1<M<1.4$ GeV as the direct signature of chiral symmetry restoration.

   ↳ nucl-thhep-phnucl-ex3 citations
5. 05*

   Applications of Fission

   A.C. Hayes🇺🇸

   This chapter is devoted to a discussion of applications of nuclear fission. It covers some aspects of the topics of nuclear reactors, nuclear safeguards and non-proliferation, reactor anti-neutrinos and nuclear medicine. It is, however, limited in scope and the reader is encouraged to explore the many other exciting sub-areas of the applications of nuclear fission.

   ↳ physics.soc-phnucl-exphysics.app-ph0 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.