arXiv subjects

Shi-Qi Zhou

Publications and source records attributed to Shi-Qi Zhou.

10 recordsLinked to original sources

arXiv2026

Timing and Spectral Studies of PSR J2022+3842 with NICER and NuSTAR

We report on the long-term timing analysis of PSR J2022+3842 using observations from the Neutron Star Interior Composition Explorer (NICER), along with spectral properties derived from joint observations with NICER and the Nuclear Spectroscopic Telescope Array (NuSTAR). Two large glitches are identified around MJD 58335 with $Δν=25.35(2)\times10^{-6}$ Hz and MJD 58875 with $Δν=52.078(6)\times10^{-6}$ Hz. Furthermore, phase-resolved spectroscopy reveals that the X-ray emission is well described by a power-law model across different phase intervals. The phase-integrated X-ray spectrum (1-79 keV) has a photon index of $Γ=1.22(7)$, yielding an unabsorbed 0.5-10 keV flux of $8.9(6)\times10^{-13}$ erg cm$^{-2}$ s$^{-1}$. The main pulse spectrum (1.2-79 keV) and the inter-pulse spectrum (1-70 keV) are harder with $Γ=1.17(4)$ and $Γ=1.03^{+0.07}_{-0.06}$ separately, producing an unabsorbed 0.5-10 keV flux of $33.2(2)\times10^{-13}$ erg cm$^{-2}$ s$^{-1}$ and $29(3)\times10^{-13}$ erg cm$^{-2}$ s$^{-1}$. Investigation of the pulse profile evolution with time shows that no significant variations were observed.

astro-ph.HE↗

arXiv2026

Investigation of the $D^{0} \rightarrow K_S^{0} π^{0} η,\ K_S^{0} π^{0} π^0$ decays

Inspired by the invariant mass distributions for the decays $D^{0} \rightarrow K_S^{0} π^{0} η$ and $D^{0} \rightarrow K_S^{0} π^{0} π^{0}$ reported by the BESIII Collaboration, we investigate these processes with an unified final state interaction formalism by incorporating both the $S$-wave pseudoscalar meson-pseudoscalar meson interactions within a chiral unitary approach and the $P$-wave contribution from the intermediate resonance $\bar{K}^*(892)$. By performing a combined fit to the invariant mass spectra and taking into account the coherence between the $S$- and $P$-waves, our results are in agreement with the experimental data. For the decay $D^{0} \rightarrow K_S^{0} π^{0} η$, the structure near 1.0 GeV in the $π^0 η$ invariant mass distribution corresponds to the signal of the $a_{0}(980)$, which is dynamically generated from the $S$-wave interactions. In the case of $D^{0} \rightarrow K_S^{0} π^{0} π^{0}$, the near-threshold enhancement in the $π^0π^0$ mass distribution arises from the combined contributions of the $f_0(500)$ and the intermediate $\bar{K}^*(892)$, while the cusp-like structure around 1 GeV$^2$ is associated with the $f_0(980)$.

hep-ph↗

arXiv2026

Long-term timing evolution of four Anomalous X-Ray Pulsars

Anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs) are believed to be manifestations of magnetars. Typically, AXPs exhibit higher X-ray luminosities, whereas SGRs are generally fainter and display significantly high signal-to-noise ratios only during their outburst phases. In this work, we report the long-term timing evolution of four AXPs: 1E 2259+586, 4U 0142+61, 1RXS J170849.0-400910 and 1E 1841-045, which were regularly monitored with NICER from 2017 to 2024. Over this period, we identify a total of 10 timing events. In addition to one glitch and one anti-glitch in 1E 2259+586 reported in literature, we detect another 8 new timing events: 5 glitches, 2 anti-glitches, and 1 unusual state transition event. Notably, both anti-glitches were observed in 4U 0142+61, making it the most frequent source of such events, and there is a hint of regular evolution in its pulse profile. In the case of 1RXS J170849.0-400910, it continues to exhibit pronounced high-frequency timing anomalies and undergoes a state transition event. Finally, we study the evolution of the pulse profiles and find that the profiles of 1E 2259+586 and 4U 0142+61 both evolve. This is consistent with the earlier finding that pulse profile evolution is a generic feature of magnetars.

astro-ph.HE↗

arXiv2026

The orbital parameters of gamma-ray binary PSR~J2032+4127

PSR~J2032+4127 is the only one of gamma-ray binary, that exhibits pulsations in gamma-ray. Previous research has indicated that the pulsar and the Be star MT91 213 orbit each other in a highly eccentric orbit with an extremely long period, with the pulsar reaching its periastron on November 13, 2017. Since its launch, the \fermi{} satellite has been monitoring this pulsar for 16 years, covering the 8 years before and the 8 years after the pulsar passed its periastron. Using these data, we present an analysis of pulse arrival times, and precisely determine the orbital parameters for the first time: the orbital period of $P_{\rm orb} \sim 52.3$ yr, the eccentricity of $e \sim 0.98$, the semimajor axis of $a$sin$i \sim 25.3$ AU, and the orbital inclination of $\sim$ 47.1$^\circ$ -- 55.1$^\circ$. We also reveal another small glitch occurred in 2021, MJD $\sim$ 59500.

astro-ph.HE↗

arXiv2025

PSR J1838-0655: X-Ray Observations with NICER and NuSTAR

We report on the timing and spectral properties of PSR J1838-0655 using joint observations from the Neutron Star Interior Composition Explorer (NICER) and the Nuclear Spectroscopic Telescope Array (NuSTAR). By disentangling the pulsar's emission from its surrounding wind nebula across joint Chandra, NuSTAR, and NICER observations, we find the pulsar's broad-band X-ray spectrum (1.3--79\,keV) is best-described by a broken power-law model. The model features photon indices of $Γ_1 = 1.19 \pm 0.07$ and $Γ_2 = 1.47 \pm 0.02$ below and above a break energy of $E_{\rm b} = 7.7 \pm 0.8$\,keV. The resulting unabsorbed 2--10\,keV flux from the pulsar is $(9.5^{+0.4}_{-0.3}) \times 10^{-12}~\mathrm{erg\,cm^{-2}\,s^{-1}}$. Furthermore, timing analysis of NICER data spanning MJD 58250 to 60630 reveals a very large glitch occurring around MJD 59300, characterized by a frequency jump of $Δν= 29.367(7) \times 10^{-6}$ Hz, which can be well explained by the vortex creep model. Phase-resolved spectral analysis indicates a clear anti-correlation between the photon index and the pulse intensity, suggesting spectral hardening at the pulse peak.

astro-ph.HE↗

arXiv2022

Higher-order generalized uncertainty principle applied to gravitational baryogenesis

The gravitational baryogenesis plays an important role in the study of the baryon asymmetry. However, the original mechanism of gravitational baryogenesis in the radiation dominated era leads to the asymmetry factor $η$ is equal to zero, which indicates this mechanism may not generate a sufficient baryon asymmetry for the standard cosmological model. In this manuscript, we investigate the gravitational baryogenesis for the generation of baryon asymmetry in the early Universe by using an new higher-order generalized uncertainty principle (GUP). It is demonstrated that the entropy and Friedman equation of the Universe deviate from the original cases due to the effect of the higher-order GUP. Those modifications break the thermal equilibrium of the Universe and in turn produces a non-zero asymmetry factor $η$. In particular, our results satisfy all three Sakharov conditions, which indicates that the scheme of explaining baryon asymmetry in the framework of higher-order GUP is feasible. In addition, confronting our theoretical results with the observational results, we constraint the GUP parameter $β_0$, whose bound between $8.4 \times {10^{10}} \sim 1.1 \times {10^{13}}$.

gr-qc↗

arXiv2022

Quantum corrections to the thermodynamics and phase transition of a black hole surrounded by a cavity in the extended phase space

In the extended phase space, we investigate the rainbow gravity-corrected thermodynamic phenomena and phase structure of the Schwarzschild black hole surrounded by a spherical cavity. The results show that rainbow gravity has a very significant effect on the thermodynamic phenomena and phase structure of the black hole. It prevents the black hole from total evaporation and leads to a remnant with a limited temperature but no mass. Additionally, we restore the $P-V$ criticality and obtaine the critical quantities of the canonical ensemble. When the temperature or pressure is smaller than the critical quantities, the system undergoes two Hawking-Page-like phase transitions and one first-order phase transition, which never occurs in the original case. Remarkably, our findings demonstrate that the thermodynamic behavior and phase transition of the rainbow SC black hole surrounded by a cavity in the extended phase space are analogous to those of the Reissner-Nordström anti-de Sitter black hole. Therefore, rainbow gravity activates the effect of electric charge and cutoff factor in the evolution of the black hole.

gr-qc↗

arXiv2022

The generalized uncertainty principle impact onto the black hole thermodynamic phase transition

In this work, we conduct a study regarding the thermodynamic evolution and the phase transition of a black hole in a finite spherical cavity subject to the generalized uncertainty principle. The results demonstrate that both the positive and negative generalized uncertainty principle parameters $β_0$ can significantly affect the thermodynamic quantities, stability, critical behavior, and phase transition of the black hole. For $β_0>0$, the black hole forms a remnant with finite temperature, finite mass, and zero local heat capacity in the last stages of evolution, which can be regarded as an elementary particle. Meanwhile, it undergoes one second-order phase transition and two Hawking-Page-type phase transitions. The Gross-Perry-Yaffe phase transition occurs for both large black hole configuration and small black hole configuration. For $β_0<0$, the Gross-Perry-Yaffe phase transition occurs only for large black hole configuration, and the temperature and heat capacity of black hole remnant is finite, whereas its mass is zero. This indicates the remnant is metastable and would be in the Hawking-Page-type phase transition forever. Specifically, according to the viewpoint of corpuscular gravity, the remnant can be interpreted as an additional metastable tiny black hole configuration, which never appears in the original case and the positive correction case.

gr-qc↗

arXiv2021

Higher-order generalized uncertainty principle corrections to the Jeans mass

The Jeans instability is regarded as an important tool for analyzing the dynamics of a self-gravitating system. However, this theory is challenging since astronomical observation data show some Bok globules, whose masses are less than the Jeans mass and still have stars or at least undergo the star formation process. To explain this problem, we investigate the effects of the higher-order generalized uncertainty principle on the Jeans mass of the collapsing molecular cloud. The results in this paper show that the higher order generalized uncertainty principle has a very significant effect on the canonical energy and gravitational potential of idea gas, and finally leads to a modified Jeans mass lower than the original case, which is conducive to the generation of stars in small mass Bok globules. Furthermore, we estimate the new generalized uncertainty principle parameter $γ_0$ by applying various data of Bok globules, and find that the range of magnitude of $γ_0$ is ${10^{11}} \sim {10^{12}}$.

physics.gen-ph↗

arXiv2021

Joule-Thomson expansion of higher dimensional nonlinearly charged AdS black hole in Einstein-PMI gravity

In this paper, the Joule-Thomson expansion of the higher dimensional nonlinearly AdS black hole with power Maxwell invariant source is investigated. The results show the Joule-Thomson coefficient has a zero point and a divergent point, which are coincide with the inversion temperature $T_i$ and the zero point of Hawking temperature, respectively. The inversion temperature increases monotonously with inversion pressure. For high-pressure region, the inversion temperature decreases with the dimensionality $D$ and the nonlinearity parameter $s$, whereas it increases with the charge $Q$. However, $T_i$ for low-pressure region increase with $D$ and $s$, while it decreases with $Q$. The ratio ${η_{\rm{BH}}}$ between the minimum of inversion temperature and the critical temperature does not depend on $Q$, it recovers the higher dimensional Reissner-Nördstrom AdS black hole case when $s=1$. However, for $s>1$, it becomes smaller and smaller as $D$ increase and approaches a constant when $D\rightarrow\infty$. Finally, we found that increase of mass $M$ and $s$, or reduce the charge $Q$ and $D$ can enhance the isenthalpic curve, and the effect of $s$ on the isenthalpic curve is much greater than other parameters.

gr-qc↗