Wed·Jan 10, 2024Wednesday·January 10, 2024

1. 01*

   Cross-shell excited configurations in the structure of 34Si

   R. S. Lubna🇺🇸 · A. B. Garnsworthy🇨🇦 · Vandana Tripathi🇺🇸 · G. C. Ball · C. R. Natzke🇨🇦 · M. Rocchini🇮🇹 · C. Andreoiu🇨🇦 · S. S. Bhattacharjee🇨🇦 · I. Dillmann🇨🇦 · F. H. Garcia🇺🇸 · S. A. Gillespie🇨🇦 · G. Hackman🇨🇦 and 14 other authors

   The cross-shell excited states of ${}^{34}$Si have been investigated via $\beta$-decays of the $4^{-}$ ground state and the $1^{+}$ isomeric state of ${}^{34}$Al. Since the valence protons and valence neutrons occupy different major shells in the ground state as well as the intruder $1^{+}$ isomeric state of ${}^{34}$Al, intruder levels of ${}^{34}$Si are populated via allowed $\beta$ decays. Spin assignments to such intruder levels of ${}^{34}$Si were established through $\gamma$-$\gamma$ angular correlation analysis for the negative parity states with dominant configurations $(\nu d_{3/2}{)}^{-1}\otimes (\nu f_{7/2}{)}^1$ as well as the positive parity states with dominant configurations $(\nu sd{)}^{-2}\otimes (\nu f_{7/2}{p}_{3/2}{)}^2$. The configurations of such intruder states play crucial roles in our understanding of the $N=20$ shell gap evolution. A configuration interaction model derived from the FSU Hamiltonian was utilized in order to interpret the intruder states in ${}^{34}$Si. Shell model interaction derived from a more fundamental theory with the Valence Space In Medium Similarity Renormalization Group (VS-IMSRG) method was also employed to interpret the structure of ${}^{34}$Si.

   nucl-exPRC(2024)·3 citations
2. 02*

   Interaction of photons with silver and indium nuclei at energies up to 20 MeV

   J.H. Khushvaktov · M.A. Demichev · D.L. Demin · S.A. Evseev · M.I. Gostkin🇷🇺 · V.V. Kobets · F.A. Rasulova · S.V. Rozov🇷🇺 · E.T. Ruziev · A.A. Solnyshkin · T.N. Tran🇺🇸 · E.A. Yakushev · B.S. Yuldashev

   The yields of photonuclear reactions in the 107Ag, 113In, and 115In nuclei have been measured. Monte Carlo simulations have been performed using the Geant4 code, and the results have been compared with the experimental ones. The isomeric ratios of the yields in the reactions 107Ag({\gamma},n)106m,gAg and 113In({\gamma},n)112m,gIn have been determined. The cross sections for the reactions 107Ag({\gamma},n)106gAg and 107Ag({\gamma},2n)105Ag at an energy of 20 MeV have been calculated on the basis of the experimental data.

   nucl-exCPC(2024)·0 citations
3. 03*

   On interpretation of fluctuations of conserved charges at high T

   T.D. Cohen🇺🇸 · L.Ya. Glozman🇦🇹

   Fluctuations of conserved charges calculated on the lattice which can be measured experimentally, are well reproduced by a hadron resonanse gas model at temperatures below T_{ch} ~ 155 MeV and radically deviate from the hadron resonance gas predictions above the chiral restoration crossover. This behavior is typically interpreted as an indication of deconfinement in the quark-gluon plasma regime. We present an argument that this interpretation may be too simple. The argument is based on the scaling of quantities with the number of colors: demonstration of deconfinement and QGP requires observable that is sensitive to N_c^2 gluons while the conserved charges are sensitive only to quarks and above T_{ch} scale as N_c^1. The latter scaling is consistent with the existence of an intermediate regime characterized by restored chiral symmetry and by approximate chiral spin symmetry which is a symmetry of confining interaction. In this regime the energy density, pressure and entropy density scale as N_c^1. In the large N_c limit this regime might become a distinct phase separated from the hadron gas and from QGP by phase transitions. A natural observable that associates with deconfinement and is directly sensitive to deconfined N_c^2-1 gluons is the Polyakov loop; in the N_c=3 world it remains very close to 0 at temperatures well above chiral crossover, reaches the value 0.5 around 3T_{ch} and the value close to 1 at temperatures ~1 GeV.

   ↳ hep-phhep-latnucl-exnucl-thEPJA(2024)·16 citations
4. 04*

   Measuring jet quenching with a Bayesian inference analysis of hadron and jet data by JETSCAPE

   R. Ehlers🇺🇸 · A. Angerami🇺🇸 · R. Arora🇺🇸 · S. A. Bass🇺🇸 · S. Cao🇺🇸 · Y. Chen🇺🇸 · L. Du🇨🇦 · H. Elfner🇩🇪 · W. Fan🇺🇸 · R. J. Fries🇺🇸 · C. Gale🇨🇦 · Y. He🇨🇳 and 41 other authors

   The JETSCAPE Collaboration reports the first multi-messenger study of the QGP jet transport parameter $\hat{q}$ using Bayesian inference, incorporating all available hadron and jet inclusive yield and jet substructure data from RHIC and the LHC. The theoretical model utilizes virtuality-dependent in-medium partonic energy loss coupled to a detailed dynamical model of QGP evolution. Tension is observed when constraining $\hat{q}$ for different kinematic cuts of the inclusive hadron data. The addition of substructure data is shown to improve the constraint on $\hat{q}$, without inducing tension with the constraint due to inclusive observables. These studies provide new insight into the mechanisms of jet interactions in matter, and point to next steps in the field for comprehensive understanding of jet quenching as a probe of the QGP.

   ↳ hep-phnucl-exnucl-thEPJ Web Conf.(2024)·4 citations
5. 05*

   Characterization and optimization of polarized and unpolarized positron production

   Sami Habet🇫🇷 · Andriy Ushakov🇫🇷 · Eric Voutier🇫🇷

   The electron induced production of positrons is a multi-parameter problem which combines elementary physics processes with complex collection systems. The optimization of this technique for 120~MeV and 1000~MeV electron beam kinetic energies is here discussed considering a tungsten target. A strong correlation between the optimum target thickness and the angular acceptance ($\Delta \theta$) of the collection system is observed, as well as sizeable differences between the optimum unpolarized and polarized operational modes. These also extend to the positron momentum and the positron polarization at the optimum, as well as the benefit of high electron beam energies for a high duty cycle positron source.

   ↳ physics.acc-phnucl-ex5 citations
6. 06*

   Production of true para-muonium in linearly polarized photon fusions

   Jian-Ping Dai🇨🇳 · Shuai Zhao🇨🇳

   True muonium (TM) -- the bound state of ${\mu }^{+}{\mu }^{-}$ -- has not been discovered yet. It was demonstrated that searching for TM via $\gamma \gamma$ fusions in heavy ion collisions is feasible due to the enhancement of the atom number. We study the production of the true para-muonium (pTM) in the collisions of linearly polarized photons in the experiments of heavy-ion collisions, calculate the production rate as well as the transverse spectrum of pTM, and explore the discovery potential in nuclear experiments. Our results show that there is a significant correlation between the linearly polarized photon distribution and the transverse momentum distribution of pTM. The optimal kinematic region of the generated pTM is identified, which can provide a theoretical guide to the detection of pTM in experiments.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2024)·10 citations
7. 07*

   Monte Carlo algorithm for calculating pre-neutron fragment mass and kinetic energy distributions from measurements using the 2E Technique for reaction 235U(nth, f)

   Modesto Montoya · Miguel Roca · Mario Alvarez

   An algorithm is proposed that enables the calculation of pre-neutron mass and energy distributions of fission fragments from uranium-235, induced by thermal neutrons, utilizing measurements obtained through the 2E technique. This algorithm facilitates the inference of the curve representing the average multiplicity of prompt neutrons relative to the pre-neutron mass of the fission fragments.

   ↳ physics.ins-detnucl-ex0 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.