Thu·Nov 20, 2025Thursday·November 20, 2025

1. 01*

   New measurement of ${}^{51}$V($\gamma$,1n) cross section through the refined monochromatic cross section extraction method

   Zi-Rui Hao · Gong-Tao Fan · Qian-Kun Sun · Hong-Wei Wang · Hang-Hua Xu · Long-Xiang Liu · Yue Zhang · Yu-Xuan Yang · Kai-Jie Chen · Zhi-Cai Li · Pu Jiao · Meng-Die Zhou and 7 other authors

   The Giant Dipole Resonance (GDR) in ${}^{51}$V has been a long-term conflicting interpretation, with existing photoneutron cross section data suggesting either a single peak or a pronounced splitting, leading to opposite conclusions on nuclear deformation. A new measurement of the ${}^{51}$V($\gamma$,1n) cross section, performed at the Shanghai Laser Electron Gamma Source (SLEGS) facility, employs a refined monochromatic cross section extraction method. By integrating Polynomial Regression and Support Vector Regression (SVR) for robust interpolation and extrapolation, the new extracted monoenergetic cross sections exhibit a single, broad peak with no evidence of GDR splitting. This result provides new support for a spherical or near-spherical shape of ${}^{51}$V. Furthermore, we found that deliberately overfitting the data using an SVR model reproduces multi-peak structures similar to those reported in historical datasets, implying that the previously claimed splitting might originated from analysis artifacts rather than physical phenomena.

   nucl-exPLB(2026)·2 citations
2. 02*

   First observation of deuteron-{\Lambda} correlations at RHIC

   STAR Collaboration

   Precise experimental information on hyperon-nucleon interactions is scarce but of paramount importance to our understanding of the inner structure of compact stars. In this letter, we report the first experimental results of correlation functions between deuterons (d) and {\Lambda} hyperons in Au+Au collisions at \sqrt{s_{NN} = 3.0 GeV measured by the STAR experiment at RHIC. A clear enhancement at small relative momenta has been observed in the correlation function. Through a Bayesian inference analysis, the source size parameters as a function of collision centrality and the spin- dependent strong interaction parameters (scattering length f0 and effective range d0) are extracted using the Lednický-Lyuboshitz formalism. The derived doublet spin state parameters (f0, d0) lead to a novel method to precisely determine {\Lambda} separation energy for the weakly bounded hypertriton ^{3}_{{\Lambda}}H.

   nucl-exhep-phnucl-thPRL(2026)·10 citations
3. 03*

   Probing Axion via Mössbauer Spectroscopy

   Shengyi Liu🇨🇳 · Kun-Feng Lyu🇺🇸 · Jie Meng🇨🇳 · Jing Shu🇨🇳 · Yakun Wang🇨🇳 · Yue Zhao🇨🇳

   We propose using the ultra-narrow 88 keV Mössbauer transition in ${}^{109}$Ag to search for QCD axion dark matter. The sub-eV axion field oscillates coherently, inducing a time-varying effective ${\bar{\theta }}_{\mathrm{QCD}}$ angle. This, in turn, modulates the nuclear binding energy. From existing linewidth measurements, we derive constraints on the $f_a^{-1}$-$m_a$ plane that already surpass other laboratory bounds. We further detail an experimental setup to directly probe this time-dependent signature via precision Mössbauer spectroscopy in the gravitational potential. This Letter demonstrates that this approach can significantly extend search capability and probe a vast, unexplored region of axion parameter space. Particularly, this setup can probe axion masses beyond the reach of existing experiments, such as atomic-clock measurements, offering a powerful new way for exploring higher-mass axion dark matter. The sensitivity has the potential to be further improved with advancing experimental capabilities.

   ↳ hep-phnucl-ex1 citation
4. 04*

   Comprehensive Assessment of ${\mathrm{Th}}^{3+}$ Properties for Nuclear Clock and Fundamental Physics Applications

   A. Chakraborty🇮🇳 · B. K. Sahoo🇮🇳

   By employing singles, doubles, and triples excitations within the relativistic coupled-cluster framework, we perform comprehensive calculations of a wide range of atomic properties for the Th${}^{3+}$ ion. These properties are essential for advancing nuclear clock technology and probing fundamental physics. Combining our isotope shift parameters with experimental data, we estimate highly accurate values of the differential nuclear charge radii for ${}^{232,229}$Th and ${}^{229m,229}$Th. Additionally, we determine the nuclear magnetic dipole and electric quadrupole moments for both the ground and isomeric states of ${}^{229}$Th by combining measured hyperfine structure constants with our theoretical calculations. Our precise evaluations of electric dipole polarizabilities and hyperfine-induced quadrupole moments are critical for assessing systematic uncertainties in ${}^{229}$Th${}^{3+}$-based nuclear clock. Notably, we observe unexpectedly significant contributions from higher-order relativistic effects and excitations involving orbitals with higher angular momentum, which markedly influence the energies of the ground state and its fine-structure partner. These results highlight the substantial challenges in achieving highly accurate predictions for these properties.

   ↳ physics.atom-phnucl-exnucl-thphysics.chem-phPRA(2026)·2 citations
5. 05*

   A relativistic mechanism for the enhanced isovector spin-orbit interaction suggested by parity-violating electron scattering experiments

   Mengying Qiu🇨🇳 · Tong-Gang Yue🇨🇳 · Zhen Zhang🇨🇳 · Lie-Wen Chen🇨🇳

   Recent high-precision parity-violating electron scattering (PVES) measurements on ${}^{208}$Pb (PREX-II) and ${}^{48}$Ca (CREX) reveal a tension in their simultaneous description within modern nuclear energy density functionals (EDFs). Analyses of these data suggest that an enhanced isovector spin-orbit interaction may help account for both measurements, but its relativistic origin in covariant density functional theory remains to be clarified. We show that, within the framework of a covariant density-dependent point-coupling EDF, an enhanced isovector tensor coupling can naturally induce such a strong isovector spin-orbit interaction. This mechanism provides a promising route toward a simultaneous description of the PREX-II and CREX results while preserving a reasonable description of finite nuclei and nuclear matter. PVES on ${}^{48}$Ca thus provides a sensitive probe of the covariant isovector tensor interaction.

   ↳ nucl-thnucl-exPLB(2026)·5 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.