Wed·Dec 3, 2025Wednesday·December 3, 2025

1. 01*

   Measuring ${}^{19,20}$O(p,n)${}^{19,20}$F reactions using an active target detector

   Rohit Kumar🇺🇸 · H. Desilets🇺🇸 · R.T. deSouza🇺🇸

   Proton capture on ${}^{19,20}$O nuclei is measured in inverse kinematics with the active target detector MuSIC@Indiana using CH${}_4$ as the target gas. Rejection of unreacted and inelastically scattered beam, along with transfer and fusion on the ${}^{12}$C allows extraction of the (p,n) cross section. As the cross-section for direct (p,n) processes at these energies is small, the measurement provides access to the proton fusion cross-section. An analysis approach that allows extraction of the proton fusion cross-section is detailed.

   nucl-ex0 citations
2. 02*

   Evidence of Spin-Interference Effects in Exclusive $J/\psi \to e^{+}{e}^{-}$ Photoproduction in Ultraperipheral Heavy-Ion Collisions

   The STAR Collaboration

   We report the first evidence of spin interference in exclusive $J/\psi \to e^{+}{e}^{-}$ photoproduction in ultraperipheral heavy-ion collisions at STAR at $\sqrt{s_{NN}}=200$~GeV. In Au+Au collisions, a negative $\cos (2\varphi )$ modulation is found for $p_T<120$~MeV/$c$ with a significance of $3.2\sigma$, while the isobar data (Ru+Ru, Zr+Zr) show a consistent negative modulation with a significance of $1.9\sigma$, opposite in sign to that in ${\rho }^0\to {\pi }^{+}{\pi }^{-}$ photoproduction. This establishes for the first time that the interference sign is controlled by the spin structure of the final-state daughters, resolving the ambiguity present in the all-boson ${\rho }^0$ channel. The compact $J/\psi$ probes gluon distributions at perturbative scales, resulting in a weaker modulation and providing stringent constraints on Color Glass Condensate calculations. These findings demonstrate that spin-dependent interference in heavy vector mesons provides a new, experimentally accessible handle on gluon structure beyond traditional cross-section measurements.

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

   Uncertainty Principle and Angular Momentum Generation in Microscopic Fission Models

   G. Scamps🇫🇷 · A. Guilleux🇫🇷 · D. Regnier🇫🇷 · A. Bernard🇫🇷

   The generation of angular momentum (intrinsic spin) in fission fragments has recently attracted renewed attention. While several microscopic approaches reproduce the spin distribution qualitatively using projection techniques, the physical origin of the fragments' angular momentum in density functional theory remains unclear. In this work, we investigate the mechanisms responsible for the spin distribution of fission fragments within a microscopic TDDFT framework. We compare spin distributions obtained from projection operators with those predicted by a simple expression derived from the uncertainty relation between angle and angular momentum, where angular fluctuations are estimated using a Monte Carlo sampling of nucleon positions. We find that a large portion of the spin distribution obtained from projection methods can be explained by the uncertainty principle. Our results thus show that, within microscopic approaches, the spin of fission fragments originates primarily from quantum uncertainty associated with their orientation angle with respect to the fission axis, mainly due to quadrupole deformation and, to a lesser extent, octupole deformation.

   ↳ nucl-thnucl-exquant-ph2 citations
4. 04*

   Muon magnetic anomaly: experimental status and prospects

   Dinko Pocanic🇺🇸

   The past five years have brought significant new results on the muon magnetic anomaly, $a_{\mu }=(g_{\mu }-2)/2$, and on the hadronic vacuum polarization (HVP) contribution dominating the uncertainty $\Delta a_{\mu }$. Serious tension has emerged between the experimental and standard model(SM) values for $a_{\mu }$, as well as between the SM and the first precise lattice QCD values. We review the current experimental and theoretical status of $a_{\mu }$, along with the prospects for new results,focusing on MUonE,a new experiment at CERN, aiming to evaluate the leading order contribution to a(HVP) in a direct measurement of muonic Bhabha scattering.

   ↳ hep-phhep-exnucl-ex0 citations
5. 05*

   Rare Event Searches Using Cryogenic Detectors via Direct Detection Methods

   S. Das🇮🇳 · R. Dey🇮🇳 · V.K.S. Kashyap🇮🇳 · B. Mohanty🇮🇳 · D. Mondal🇮🇳 · S. Banik🇦🇹 · M. Chaudhuri🇨🇳 · V. Iyer🇨🇦

   Cryogenic detectors are at the forefront of rare-event search experiments, including direct detection of dark matter, coherent elastic neutrino-nucleus scattering, neutrinoless double-beta decay, and searches for fractionally charged particles. Their unique ability to achieve ultra-low energy thresholds, typically O(eV-100 eV), together with excellent energy resolution and effective background suppression, makes them sensitive to extremely faint signals from rare interactions. These rare particle interactions produce phonons, ionization, or scintillation, depending on the target medium, which are registered by specialized sensors and converted into measurable signals. This review summarizes the underlying detection principles, surveys major experiments and recent results, examines forthcoming initiatives, and outlines the evolving role of cryogenic detectors in advancing the frontiers of rare-event physics.

   ↳ hep-exnucl-exphysics.ins-detMod.Phys.Lett.A(2026)·3 citations
6. 06*

   Demonstration of magic dressing of ${}^3$He

   Raymond Tat🇺🇸

   A common concern in high-precision neutron electric dipole moment (nEDM) experiments is that of magnetic field stability. For static fields, this problem can be mitigated through the use of a superconducting holding field coil, which when operated in persistent current mode serves to stabilize the magnetic field. However, such a solution is not viable when time-varying magnetic fields are present, as is the case for the spin dressing mode of the proposed nEDMSF (nEDM super-fluid) experiment. This experiment features an oscillating magnetic field to dress the gyromagnetic ratios of ${}^3$He and neutrons to the same value, a condition known as critical dressing. Fluctuations in the dressing field amplitude have the potential to disrupt this condition. Here, we investigate a modification to spin dressing, termed ``magic dressing,'' which renders the system insensitive to small variations in dressing field amplitude. We further demonstrate the utility of this method for the single spin-species case using a sample of polarized ${}^3$He. We find a dramatic increase in transverse relaxation time in the presence of magnetic field gradients.

   ↳ physics.atom-phcond-mat.othernucl-ex1 citation
7. 07*

   Neutron-deuteron scattering revisited with the EKM chiral nuclear force and the WPCD method

   Qing-Yu Zhai🇨🇳 · Dan-Yang Pang🇨🇳 · Wen-Di Chen🇨🇳 · O. A. Rubtsova🇷🇺 · Rui-Rui Xu🇨🇳 · Jun-Xu Lu🇨🇳 · Haozhao Liang🇯🇵 · Li-Sheng Geng🇨🇳

   We revisit the neutron-deuteron scattering using the Wave-Packet Continuum Discretization (WPCD) method with the EKM chiral nuclear force at various chiral orders. We rederive the permutation operator and solve the Faddeev-AGS equations directly, without rewriting the initial Faddeev kernel $t{G}_0$ and introducing pseudo-states, thereby rendering the approach easily extendable to a relativistic framework. We find that up to the next-to-next-to-next-to-leading order (N${}^3$LO), although one can well describe the differential cross sections, one cannot resolve the long-standing $A_y$ puzzle, consistent with previous studies. The fact that the N${}^3$LO chiral forces can well describe the $NN$ phase shifts and the results obtained with the EKM and Idaho N${}^3$LO chiral forces agree with each other underscores the need for further investigations to resolve the $A_y$ puzzle, e.g., considering three-body forces or relativistic effects.

   ↳ nucl-thhep-phnucl-exPRC(2026)·1 citation

* 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.