Chinese Physics C

Highlights

Physical parameter regression from black hole images using a multiscale adaptive neural network
Jialei Wei, Ao Liu, Dejiang Li, Cuihong Wen

2025, 49(12): 125105. doi: 10.1088/1674-1137/adf542

HTML

PDF

HTML

PDF

High-precision regression of physical parameters from black hole images generated by General Relativistic Ray Tracing (GRRT) is essential for investigating spacetime curvature and advancing black hole astrophysics. However, owing to limitations in observational resolution, high observational costs, and imbalanced distributions of positive and negative samples, black hole images often suffer from data scarcity, sparse parameter spaces, and complex structural characteristics. These factors pose significant challenges to conventional regression methods based on simplified physical models. To overcome these challenges, this study introduces the Multiscale Adaptive Network (MANet), a novel regression framework grounded in deep learning. MANet integrates an Adaptive Channel Attention (ACA) module to selectively enhance features in physically informative regions. Meanwhile, a Multiscale Enhancement Feature Pyramid (MEFP) is employed to capture fine-grained spatial structures, such as photon rings and accretion disks, while alleviating information loss due to downsampling. Experimental evaluations on GRRT-simulated datasets demonstrate that MANet substantially improves parameter estimation accuracy and generalization capability in high-dimensional parameter spaces, outperforming existing baseline approaches. This framework presents a promising avenue for high-precision parameter regression in Event Horizon Telescope (EHT) data analysis and broader astrophysical imaging applications characterized by sparse and noisy data.
On the pole trajectory of the subthreshold negative parity nucleon with varying pion masses
Qu-Zhi Li, Zhiguang Xiao, Han-Qing Zheng

2025, 49(12): 123103. doi: 10.1088/1674-1137/adfa02

HTML

PDF

HTML

PDF

We study the pole trajectory of the recently established subthreshold negative-parity nucleon pole, namely the $N^*(920)$, with varying pion masses in the scheme of linear σ model with nucleons, using the $N/D$ unitarization method. We find that, as the pion mass increases, the pole moves toward the real axis. For larger pion masses, at tree level, the pole falls to a specific point on u-channel cut and crosses to the adjacent Riemann sheet defined by the logarithmic u-channel cut. At the one-loop level, the pole does not meet the u-cut up to $m_\pi=0.36$ GeV. We also re-examined the σ pole trajectory and found it to be in good agreement with the Roy equation analysis result.
Feasibility study of measuring interaction cross sections of hypernuclei produced in projectile fragmentation reactions with WASA-FRS setup
Yiming Gao, Yoshiki K. Tanaka, Vasyl Drozd, Hiroyuki Ekawa, Samuel Escrig, Yan He, Ayumi Kasagi, Enqiang Liu, Manami Nakagawa, Christophe Rappold, Takehiko R. Saito, Ryohei Sekiya, He Wang, Ayari Yanai, Xiaohong Zhou

2025, 49(12): 124003. doi: 10.1088/1674-1137/adf4b2

HTML

PDF

HTML

PDF

A novel method is proposed to measure the interaction cross sections of short-lived hypernuclei with the WASA-FRS experimental setup at GSI and FAIR. The interaction cross sections of hypernuclei, produced in projectile fragmentation reactions at relativistic energies, can be determined from their production point distribution within a target. The feasibility of such a measurement is evaluated through detailed Monte Carlo simulations. The results indicate that an aimed uncertainty on the order of 10% can be achieved for the case of a hypertriton, demonstrating the potential of this method for studying matter radii and the possible hyperon halo structure of hypernuclei.

Just Accepted

More >

Neutron Leakage Spectra Benchmark of Spherical Polyethylene Sample with a ²⁵²Cf fission Source
Chang-Lin Lan, Kuo-Zhi Xu, Yu-Ting Wei, Yang-Bo Nie, Xiao-Dong Pan, Yan-Yan Ding, Shi-Yu Zhang, Hao-Nan Li, Bo Gao, Bo Xie, Xi-Chao Ruan, Shi-Long Liu

Published: 2025-12-02

HTML

PDF

Published: 2025-12-02

HTML

PDF
Interplay of Lyapunov exponents, phase transitions and chaos bound in nonlinear electrodynamics black hole
Chuanhong Gao, Chuang Yang, Tetvui Chong, Deyou Chen

Published: 2025-11-29, doi: 10.1088/1674-1137/ae210d

HTML

PDF

Published: 2025-11-29, doi: 10.1088/1674-1137/ae210d

HTML

PDF
95 GeV Higgs boson and nano-Hertz gravitational waves from domain walls in the N2HDM
Haotian Xu, Yufei Wang, Xiao-Fang Han, Lei Wang

Published: 2025-11-29, doi: 10.1088/1674-1137/ae2082

HTML

PDF

Published: 2025-11-29, doi: 10.1088/1674-1137/ae2082

HTML

PDF

Recent

More >

Alpha-decay systematics and a new scaling law in heavy and superheavy nuclei
Hisham Anwer, A. R. Abdulghany

2026, 50(1): 014111-014111-16. doi: 10.1088/1674-1137/ae0307

Show Abstract

This paper presents a systematic investigation of α-decay properties in even-even isotopic chains of Po ($ Z=84 $), Cm ($ Z=96 $), Hs ($ Z=108 $), and Fl ($ Z=114 $) using a semi-classical approach. Ground-state properties, including binding energies and nucleon density distributions, are calculated by minimizing a Skyrme-based energy density functional augmented with microscopic corrections. The derived nuclear densities and $ Q_\alpha $-values are used to construct the α decay potential through the double-folding model (DFM). The α-decay dynamics are treated quantum mechanically based on the preformed cluster model (PCM) within the Wentzel-Kramers-Brillouin (WKB) approximation. The analysis reveals distinct signatures of spherical shell closures at $ N=126 $ and $ N=184 $, along with secondary anomalies near $ N = 148 $, $ 152 $, and $ 162 $, which are consistent with deformed sub-shell effects predicted by nuclear structure models. The signature of daughter nuclear stability is systematically observed through one or more of the following features: shortened α-decay half-lives, enhanced $ Q_\alpha $ values, increased penetrabilities, and/or reduced assault frequencies. A new universal scaling relation, relating the decay half-lives and a scaled combination of nuclear charge and decay energy, is established, showing strong correlation across a wide mass range. Systematic comparisons demonstrate particular predictive advantages for superheavy nuclei, with the proposed method accurately reproducing observed half-life variations across all isotopic chains. The results confirm the sensitivity of α-decay observables to both spherical and deformed shell effects and reinforce the role of α-decay systematics as powerful tools for probing nuclear structure and guiding predictions in unexplored regions of the nuclear chart.

HTML

PDF
Erratum and Addendum: Improvement of nuclear semi-empirical mass formula by including shell effect (Chin. Phys. C, 49(11): 114103 (2025))
Qing Wu, Wei-Feng Li, Zhong-Ming Niu, Hao-Zhao Liang, Min Shi

2025, 49(12): 129001-129001-1. doi: 10.1088/1674-1137/ae23a6

Show Abstract

HTML

PDF
Cross section measurement of the ⁶Li(n,t)⁴He reaction in the MeV neutron energy range
Yu. M. Gledenov, I. Chuprakov, Guohui Zhang, G. Khuukhenkhuu, M. Odsuren, B. Usukhbayar, L. Krupa, E. Sansarbayar, Jie Liu, Haofan Bai, Cong Xia, Zepeng Wu, Wenkai Ren, D. Berikov, G. Ahmadov, A. K. Bekbayev, B. Mukhametuly, E. S. Korshikov, N. T. Temerbulatova, E. B. Myrzabekova, O. Daulbayev, Y. Arynbek

2025, 49(12): 124004-124004-8. doi: 10.1088/1674-1137/ae0306

Show Abstract

Cross sections of the ⁶Li(n, t)⁴He reaction were measured in the fast neutron energy range from 3.3 to 5.3 MeV using a gridded ionization chamber (GIC) and well–calibrated experimental setup at the EG–5 Van de Graaff accelerator of the Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research (FLNP, JINR). Lithium fluoride (⁶LiF) samples with varying thicknesses and krypton–CO₂ gas mixtures with different pressures were used to optimize the detection of both alpha particles and tritons. Neutron fluxes were monitored using two high–purity (99.999%) ²³⁸U₃O₈ samples placed inside the GIC, complemented by an externally calibrated ³He long counter. The measured ⁶Li(n, t)⁴He cross–section data were compared with existing results of measurements and evaluations from EXFOR and ENDF nuclear data libraries, and the results showed a good agreement in the measured neutron energy range. These new measurements provide reliable cross–section data that contribute to the refinement of evaluated nuclear data files and support applications in nuclear physics, tritium production, and reactor design.

HTML

PDF

Current Issued

2025 Vol. 49, No. 11
Published: 01 November 2025

Particles And Fields
Nuclear Physics
Particle And Nuclear Astrophysics And Cosmology