PaperPanorama

Nuclear Experiment·nucl-ex

Thu·Sep 10, 2026

7 papers—3 primary·4 cross-listed

All7Primary3Cross-lists4
  1. 01

    Detailed experimental study of excited states in Ti via the and reactions

    B. Kelly🇺🇸 · M. Spieker🇺🇸 · L. T. Baby🇺🇸 · S. Baker🇺🇸 · A. L. Conley🇺🇸 · D. Houlihan · K. W. Kemper🇺🇸 · E. Litvinova🇺🇸 · N. Tsoneva · A. Volya🇺🇸

    Excited states of semi-magic Ti were studied up to the neutron-separation energy via the and reactions. In total, 82 excited states were identified based on the measurement of angular distributions with the Super-Enge Split-Pole Spectrograph (SE-SPS) at Florida State University. From the experimental data, sum rules related to vacancies were calculated for the , , , , and neutron single-particle orbitals and compared to predictions obtained with the time-dependent continuum shell model (TDCSM), the quasiparticle-phonon model (QPM), and the relativistic equation of motion theory (REOM). A comparison for the data obtained for Ti and Ti is also presented, focusing on differences of the single-particle strength fragmentation in even- and odd- nuclei.

    nucl-exnucl-th0 citations
  2. 02

    Reinvestigation of the Yield of the Trinity Device

    Eric B. Norman · Keenan J. Thomas🇺🇸 · Pedro V. Guillaumon🇮🇹

    Previous published analyses of trinitite to determine the yield of the Trinity nuclear explosion used various estimates of the fraction of fission products that became incorporated in trinitite. Furthermore, these studies utilized nuclear data that has subsequently been revised. Utilizing a planar germanium detector, we observed gamma rays produced by the decays of both 137Cs and 239Pu from four samples of trinitite. From the observed 137Cs/239Pu ratios of and a simple analysis method based on current nuclear data and weapons debris studies, we find an average yield of 9.1+-4.5 kilotons from our four samples. While this result is substantially lower than the established total yield of 21 kilotons, it is in reasonable agreement that attributable to fissions in the 239Pu core alone.

    nucl-exphysics.hist-phAppl.Radiat.Isot.(2026)·0 citations
  3. 03

    Search for neutrinoless quadruple beta decay of Xe in PandaX-4T detector

    PandaX Collaboration: Zhiyuan Li🇨🇳 · Peiyuan Chen🇨🇳 · Wei Chen🇨🇳 · Xiaohua Chen🇨🇳 · Xun Chen🇨🇳 · Yunhua Chen🇨🇳 · Chen Cheng🇨🇳 · Xiangyi Cui🇨🇳 · Yuxin Cui🇨🇳 · Manna Deng🇨🇳 · Roni Dey🇨🇳 · Yingjie Fan🇨🇳 and 93 other authors

    The observation of neutrinoless quadruple beta decay (04) in the absence of neutrinoless double beta decay (02) has been argued to provide a strong indication that neutrinos are Dirac particles. We report a search for 04 decay of using a total exposure of 148.4 kgyr, collected during the commissioning and the first science runs of the PandaX-4T experiment. No significant excess of events over the background is observed. A lower limit on the 04 decay half-life of is set at 6.01 x yr at the 90% confidence level. This result establishes the most stringent constraint on this process in xenon, demonstrating the unique capability of the PandaX-4T detector in probing lepton number violation and shedding light on the fundamental nature of neutrinos.

    nucl-exhep-ex0 citations
  4. 04

    Bridging Theory and Data: Correcting Nuclear Mass Models with Interpretable Machine Learning

    Yanhua Lu · Tianshuai Shang · Pengxiang Du · Jian Li🇨🇳 · Haozhao Liang🇯🇵

    Nuclear mass prediction is one of the core issues in nuclear physics research, yet it faces the challenge of small-sample datasets with high complexity. This study introduces the Kolmogorov-Arnold Network (KAN) into the refinement of nuclear mass models, proposing an efficient and interpretable solution. By constructing the KAN-WS4 hybrid model, the prediction accuracy is significantly improved (the root mean square error is reduced from 0.3 MeV to 0.16 MeV). Furthermore, leveraging the intrinsic interpretability of KAN, feature importance analysis reveals that the proton number is the most critical factor influencing residuals, indicating potential systematic biases in proton-related terms within existing theoretical models. The method's generality is demonstrated across five mass models. This study shows that KAN provides a novel approach to small-sample, high-complexity scientific problems. Its interpretability facilitates the data-driven discovery of physical laws, promising broad applicability to key nuclear physics issues.

    ↳ nucl-thcs.LGnucl-ex1 citation
  5. 05

    Spectral Discrimination of Deposited Gamma-Ray Energies in a Simulated CeBr Scintillator

    Andrey Elagin

    We show that wavelength measurements of individual detected optical photons may provide additional information about gamma-ray energy deposited in a CeBr crystal when the detected-photon-count distributions overlap for nearby gamma-ray energies. Monoenergetic 662 and 629 keV gammas are used in a Geant4 simulation of a CeBr crystal. Assuming a light yield of photons/MeV, a wavelength-independent photon-detection efficiency of 30%, and a wavelength resolution of nm, we find that the fraction of photons reconstructed above 385 nm gives an event-level separation of 2 standard deviations between the 662 and 629 keV event populations selected within the same 1%-wide detected-photon-count interval. No timing or reconstructed interaction-position information is used. The result demonstrates, within the present simulation model, that event-dependent optical spectra can retain energy information beyond an undifferentiated photon count.

    ↳ physics.ins-detnucl-ex0 citations
  6. 06

    Development of the {\gamma} strength function with the neutron number

    Stefan Frauendorf · Ronald Schwengner🇩🇪 · Gowhar Bhat🇮🇳 · Javid Sheikh

    The M1 and E2 {\gamma} strength functions ({\gamma}sf) have been calculated for extended series of the Mo, Fe, Sn, Ge and Gd isotopes using the conventional spherical shell model (SSM) and, as a new tool, the triaxial projected shell model (TPSM). For almost all cases the strong enhancement of the M1 {\gamma}sf (low energy magnetic radiation-LEMAR) is found. In the mid-shell region, a bimodal structure of the LEMAR spike and a bump around 3 MeV, interpreted as the scissors resonance (SR), develops. The combination of LEMAR and the SR is generated by the splitting of the spherical single particle multiplets of given j caused by deformation and their fragmentation over nearby quasiparticle configurations.

    ↳ nucl-thnucl-ex0 citations
  7. 07

    Systematic study of E2 matrix elements in the framework of the Triaxial Projected Shell Model

    Stefan Frauendorf · Syed Rouoof · Gowhar Bhat🇮🇳 · Sheikh Jehangir🇮🇳 · Nazira Nazir · Kouser Qureshie · Niyaz Rather · Javid Sheikh

    Nuclides for which extended sets of E2 matrix elements have been measured by means of COULEX experiments are studied in the framework of the triaxial projected shell model (TPSM). The studies encompass: 70,72,74,76Ge, 76,78,80,82Se, 100Mo, 104Ru, 110Pd, 168Er, 186,188,190Os, 184Pt. The experimental energies of the ground band, of the quasi gamma band and of some excited 0+ bands as well as their individual intra and inter band matrix E2 matrix elements are systematically accounted for by the microscopic TPSM calculations.

    ↳ nucl-thnucl-ex0 citations

Affiliations

first authorsco-authorsvia INSPIRE