Mon·Aug 4, 2025Monday·August 4, 2025

1. 01*

   Evidence for shape coexistence in ${}^{120}$Sn from the first $0_3^{+}$ lifetime measurement

   F. Wu🇨🇦 · C. Andreoiu🇨🇦 · V. Karayonchev🇺🇸 · C.M. Petrache🇫🇷 · J.-M. Régis🇩🇪 · A. Esmaylzadeh🇩🇪 · C. Michelagnoli🇫🇷 · M. Beuschlein🇩🇪 · P. Spagnoletti🇨🇦 · G. Colombi🇫🇷 · J.M. Daugas🇫🇷 · L. Domenichetti🇫🇷 and 5 other authors

   The lifetime of the $0_3^{+}$ state in ${}^{120}$Sn was measured for the first time applying the fast-timing technique following thermal neutron capture. The mean lifetime of $\tau =50(7)$~ps leads to a $E0$ transition strength of $10^3\times {\rho }^2(E0;0_3^{+}\to 0_2^{+})=120(50)$, suggesting shape coexistence and a high degree of mixing between the $0_2^{+}$ and $0_3^{+}$ states. With the newly measured lifetime, the $B(E2;0_3^{+}\to 2_1^{+})$ value is 0.50(7)~W.u., which reveals that the ${\rho }^2(E0;0_3^{+}\to 0_1^{+})$ increases by a factor of $\approx 3.4$ from ${}^{116}$Sn to ${}^{120}$Sn.

   nucl-exPRC(2025)·2 citations
2. 02*

   Neutron emission following nuclear muon capture on palladium isotopes

   T. Y. Saito🇯🇵 · M. Niikura🇯🇵 · T. Matsuzaki🇯🇵 · S. Abe🇯🇵 · K. Ishida🇯🇵 · S. Kawase🇯🇵 · Y. Kawashima🇯🇵 · T. Koiwai🇯🇵 · K. Matsui · S. Momiyama · A. Nambu · H. Otsu🇯🇵 and 8 other authors

   The energy spectra of the neutrons emitted following nuclear muon capture on palladium isotopes ($A=104$, 105, 106, 108, and 110) were measured using isotopically enriched target. \item[Method] The experiment was performed at the MuSIC-M1 beamline at the Research Center for Nuclear Physics (RCNP), Osaka University. The neutrons and $\gamma$ rays were detected with twenty-one liquid scintillators and BaF${}_2$ detectors. The time-of-flight method was used to determine the neutron energy. \item[Results] Neutron energy spectra from 1\,MeV up to 20\,MeV were measured for five palladium isotopes, providing the first systematic data in the $A\sim 100$ region. The spectral shapes were compared with the previous measurement for heavy nuclei and theoretical calculations. The neutron-neutron opening angle distribution was also measured and an indication of small angle correlation was found. \item[Conclusions] The spectral shape below 4\,MeV was well explained consistently with the previous measurement by the evaporation model introducing a mass number scaling. The neutron energy spectrum around 10\,MeV plays a key role in understanding the dynamics of the nuclear muon capture reaction because it is the result of the transition from the direct and pre-equilibrium neutron emission onto the evaporation process.

   nucl-ex2 citations
3. 03*

   Determination of proton and neutron contributions to the $0_{g.s.}^{+}\to 2_1^{+}$ excitations in ${}^{42}$Si and ${}^{44}$S using inelastic proton scattering in inverse kinematics and intermediate energy Coulomb excitation

   L.A. Riley🇺🇸 · I. Conroy🇺🇸 · A. M. Himmelreich · M. Heinze · J. Kosa · B. McNulty · P. D. Cottle🇺🇸 · M. Spieker🇺🇸 · A. Volya🇺🇸 · A. L. Conley🇺🇸 · D. Houlihan · B. Kelly🇺🇸 and 17 other authors

   We have measured the $0_{g.s.}^{+}\to 2_1^{+}$ transition in the neutron rich $N=28$ isotope ${}^{42}$Si using the probes of intermediate energy Coulomb excitation and inelastic proton scattering in inverse kinematics at the Facility for Rare Isotope Beams with beam particle rates of $\approx 5$ particles/s. The results of these two measurements allowed us to determine $M_n/M_p$, the ratio of the neutron and proton transition matrix elements for the $0_{g.s.}^{+}\to 2_1^{+}$ transition. In addition, we have measured the $0_{g.s.}^{+}\to 2_1^{+}$ transition in the isotone ${}^{44}$S using inverse kinematics inelastic proton scattering. By comparing the ${}^{44}$S proton scattering result with a recent intermediate energy Coulomb excitation result on the same transition, we were able to determine $M_n/M_p$ for the $0_{g.s.}^{+}\to 2_1^{+}$ transition in this nucleus as well. This work strengthens the evidence that ${}^{42}$Si has a stable quadrupole deformation in its ground state and that ${}^{44}$S does not. Both conclusions are further supported by shell model calculations carried out with the FSU interaction.

   nucl-exPRC(2025)·5 citations
4. 04*

   Thermoelectric figure of merit and the deconfinement phase transition

   Kamaljeet Singh🇮🇳 · Raghunath Sahoo🇮🇳

   Thermoelectric phenomena are traditionally associated with the interconversion of thermal and electrical energy in many-body systems. In the context of high-temperature quantum chromodynamics (QCD) matter produced in relativistic heavy-ion collisions, thermoelectric responses can provide insight into the evolving microscopic dynamics and the redistribution of effective degrees of freedom across the phase transition region. In this work, for the first time, we present a phenomenological study of the thermoelectric figure of merit (\( ZT \)) in hot QCD matter, with a particular focus on its behavior across the hadronic and quark-gluon plasma phases. Using model-based calculations for the electrical conductivity, Seebeck coefficient, and thermal conductivity, we analyze the temperature dependence of \( ZT \) and identify characteristic features near the QCD phase transition temperature. Our results indicate that \( ZT \) exhibits nontrivial behavior near the transition region, reflecting the changing transport properties and active degrees of freedom in the medium. This phenomenological study of the thermoelectric figure of merit provides a complementary perspective to traditional transport studies and may provide critical insights for advancing the understanding of QCD matter through the transition region.

   ↳ hep-phhep-exhep-thnucl-ex+1PLB(2026)·2 citations
5. 05*

   Series Testing and Characterization of 1100 Hamamatsu H12700 Multianode Photomultiplier Tubes

   J. Förtsch🇩🇪 · K.-H. Kampert🇩🇪 · V. Patel🇩🇪 · C. Pauly🇩🇪 · D. Pfeifer🇩🇪

   Both the future CBM-RICH and the recently upgraded HADES-RICH use Hamamatsu H12700 Multi-Anode Photomultipliers (MAPMTs) as their photon detectors. To test the MAPMTs thoroughly before using them in the detectors, the photon sensors were qualified well in advance and a test bench was built to efficiently characterize each MAPMT. The test bench measures the single photoelectron gain, dark rate, relative efficiency, and afterpulse probability of each channel. This article describes the operating principle of the test bench and discusses the distributions of each measured quantity over 1,100 MAPMTs. Additionally, the long-term aging effects of the H12700 MAPMT are investigated based on repeated measurements of individual MAPMTs.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2026)·1 citation
6. 06*

   Coupled-channel contributions to the GDH sum rule from the Jülich-Bonn approach

   Carolin Schneider🇩🇪 · Deborah Rönchen🇩🇪 · Christoph Hanhart🇩🇪 · Ulf-G. Meißner🇩🇪

   We study the Gerasimov-Drell-Hearn (GDH) sum rule within a dynamical coupled-channel approach, the Jülich-Bonn model for light baryon resonances based on fits to an extensive data base of pion and photon induced data. Recently published photoproduction data for different observables with $\pi N$ and $\eta N$ final states are analyzed simultaneously with older data for the reactions $\pi N\to \pi N$, $\eta N$, $K\Lambda$, $K\Sigma$ and $\gamma p\to \pi N$, $\eta N$, $K\Lambda$, $K\Sigma$. The impact of the new data on the resonance spectrum is investigated and the contribution of the individual channels to the GDH integral is determined.

   ↳ nucl-thhep-phnucl-exEPJA(2025)·2 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.