PaperPanorama

Nuclear Experiment·nucl-ex

Thu·Sep 24, 2026

4 papers—1 primary·3 cross-listed

All4Primary1Cross-lists3
  1. 01

    Probing the C+C fusion reaction via zero-degree spectator measurement in the C(N,)Ne quasi-free reaction

    Xue-Jian Wang · Qun-Gang Wen · Cheng-Bo Li · Hui-Ming Jia · Jian-You Guo · Cheng-jian Lin · Lei Yang · Feng Yang · Nan-ru Ma · Pei-wei Wen · Tian-peng Luo · Chang Chang and 5 other authors

    The 12C+12C fusion reaction is a key physical process in stellar evolution and supernova explosions. It not only determines the late evolutionary fate of massive stars but also directly influences the critical conditions for triggering Type Ia supernovae in accreting white dwarfs. In this work, the THM was employed to investigate the 12C(12C,a0)20Ne reaction channel of the 12C+12C fusion process, using 14N as the Trojan horse nucleus. Telescope detectors were placed at 0 and 15 deg. to design two experimental configurations covering the forward-angle regions where spectator particles are most likely to emerge. By applying the DWBA, two sets of astrophysical S*(E) factors for the two-body reaction 12C(12C,a0)20Ne were extracted from the three-body reaction 12C(14N,da0)20Ne and normalized to existing experimental data. The results show that, limited by the overall experimental resolution, the present study cannot resolve fine resonance structures. Within the astrophysical energy region of 0.5-2 MeV, the extracted S*(E) factor exhibits an increasing trend toward lower energies. The S*(E) factor obtained with the 0-deg configuration shows a flatter trend than that obtained with the 15-deg configuration. Supported by the quasi-free reaction simulation results, the divergence between the two data sets may reflect a combination of experimental acceptance effects, finite detector resolution, and possible differences in the relative contributions of reaction mechanisms. This study provides a systematic examination of the experimental design, quasi-free event selection strategy, and interpretation of the underlying physical mechanisms, serving as a useful reference for understanding the role of the 12C+12C fusion reaction in astrophysical processes.

    nucl-ex
  2. 02

    A rotation-based Hall-probe magnetic compass

    B. Wojtsekhowski · C. Cuevas · R. Dawson · W. Henry · N. Liyanage · G. Ron · J. Wilson

    In many physics and space experiments the direction of a magnetic field must be known to one milliradian or better. We have developed a new type of magnetic compass, based on rotation, in which a spinning Hall probe (HP) produces an alternating signal proportional to the component of the magnetic field transverse to the axis of rotation. Aligning the rotation axis so that this signal vanishes gives the direction of the field. The device requires no calibration and is insensitive to electronics drift. A spinning-HP compass was built and used in a recent experiment at Jefferson Lab, where it determined the direction of the 25~G holding field of a polarized He target to about 1~mrad; the direction of the rotation axis was transferred to the laboratory frame with a laser and a flat mirror attached to the rotor. A second implementation of the rotation approach, a spinning field concentrator (SFC) with a stationary Hall probe, was also built. With 10 seconds of averaging the SFC compass resolves a transverse field of 18~G, corresponding to a directional resolution of 70~rad in a field of 0.25 G, close to the Earth's field.

    ↳ physics.ins-dethep-exnucl-ex
  3. 03

    Multi-Model Analysis of the Astrophysical Factor for the Reaction and Its Impact on Astrophysical Reaction Rates

    Xue-Jian Wang · Wei-Ke Nan · Qing Wang · Tian-Yu Tao · Qun-Gang Wen · Jian-You Guo · Cheng-Bo Li · Hui-Ming Jia

    The reaction is a destruction process for in stars and the Big Bang. The Trojan Horse Method (THM) is a well-established indirect technique that enables the determination of reaction cross sections within the Gamow energy region while avoiding the uncertainties associated with low-energy extrapolations of the factor and electron-screening effects. In this work, the bare-nucleus THM data reported by Wen \textit{et al.} are systematically analyzed using polynomial fitting, a double Breit--Wigner model, and the -matrix formalism. The applicability and physical implications of these theoretical approaches in describing the low-energy factor of the reaction are investigated and compared. Since the THM data have been incorporated into the NACRE II reaction-rate compilation, leading to improved accuracy in reaction-rate evaluations, the refined theoretical analysis presented here provides further insight into the underlying reaction dynamics and establishes a more reliable foundation for stellar reaction-rate calculations. The results obtained in this work offer valuable reference for future high-precision experimental investigations and the development of theoretical models in nuclear astrophysics.

    ↳ nucl-thastro-ph.SRnucl-exThe Astrophysical Journal, 1008:119 (9pp)…
  4. 04

    Shell structure and spontaneous decay of superheavy isotopes with the deformed relativistic Hartree-Bogoliubov theory in continuum

    Yumeng Wang · Lang Liu · Cong Pan

    Shell structure and spontaneous decay of isotopes are systematically investigated using the deformed relativistic Hartree-Bogoliubov theory in continuum (DRHBc) with the PC-PK1 density functional. By accounting for deformation and continuum effects, the neutron drip line is predicted to be located at , and eight potential multi-neutron emitters beyond the neutron drip line are identified. The results, compared with the spherically constrained case, highlight the critical role of deformation effects in determining the ground-state properties of superheavy nuclei. In addition, potential neutron shell closures emerge at and , alongside subshell closures at and . The results disfavor as a possible proton magic number and suggest and as more favorable candidates for proton shell closures in the superheavy region. Finally, the competition between decay, decay, and spontaneous fission is analyzed by calculating half-lives within various semi-empirical formulas. The results indicate that decay is the predominant mode on the proton-rich side, whereas spontaneous fission and decay gradually become dominant with increasing neutron number.

    ↳ nucl-thnucl-ex