A5089891347- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Astrophysics and Cosmic Phenomena
- Astro and Planetary Science
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Cosmology and Gravitation Theories
- High-pressure geophysics and materials
- Solar and Space Plasma Dynamics
- SAS software applications and methods
- Mechanics and Biomechanics Studies
- Astrophysics and Star Formation Studies
- Superconducting Materials and Applications
- Statistical and numerical algorithms
- Heat Transfer Mechanisms
- Streptococcal Infections and Treatments
- Laser-Plasma Interactions and Diagnostics
- Nuclear Physics and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Geological and Geophysical Studies
- Multidisciplinary Science and Engineering Research
- Crystallography and Radiation Phenomena
- Geophysics and Sensor Technology
Huazhong University of Science and Technology
2016-2025
University of Nevada, Las Vegas
2011-2017
Purple Mountain Observatory
2014
Chinese Academy of Sciences
2012-2014
Nanchang University
2008
Shanxi Normal University
2008
Double neutron star (DNS) merger events are promosing candidates of short Gamma-ray Burst (sGRB) progenitors as well high-frequecy gravitational wave (GW) emitters. On August 17, 2017, such a coinciding event was detected by both the LIGO-Virgo detector network GW170817 and Gamma-Ray Monitor on board NASA's {\it Fermi} Space Telescope GRB 170817A. Here we show that fluence spectral peak energy this sGRB fall into lower portion distributions known sGRBs. Its isotropic luminosity is abnormally...
One favored progenitor model for short duration gamma-ray bursts (GRBs) is the coalescence of two neutron stars (NS–NS). possible outcome such a merger would be rapidly spinning, strongly magnetized star (known as millisecond magnetar). These magnetars may "supra-massive," implying that they collapse to black holes after losing centrifugal support due magnetic dipole spin down. By systematically analyzing Burst Alert Telescope (BAT)-XRT light curves all GRBs detected by Swift, we test how...
We present a time-resolved spectral analysis of 51 long and 11 short bright GRBs observed with the {\em Femri}/GBM, paying special attention to $E_{\rm p}$ evolution within same burst. Among 8 single-pulse GRBs, 5 show hard-to-soft evolution, while 3 intensity-tracking. The multi-pulse have more complicated patterns. whose spectrum is available for first pulse, almost half (15/32 GRBs) clear other (17/32 Later pulses typically tracking behavior, although pattern was identified in 2nd pulse 2...
A hyperaccreting stellar-mass black hole has been long speculated as the best candidate for central engine of gamma-ray bursts (GRBs). Recent rich observations GRBs by space missions such Swift and Fermi pose new constraints on GRB models. In this paper, we study baryon-loading processes a jet launched from engine. We consider relativistic powered -annihilation or Blandford–Znajek (BZ) mechanism. baryon loading neutrino-driven wind neutrino-cooling-dominated accretion flow. For magnetically...
Fast radio bursts (FRBs) are characterized by millisecond durations, high Galactic latitude positions, and dispersion measures. Very recently, the cosmological origin of FRB 150418 has been confirmed \cite{kea16}, FRBs now strong competitors as probes. The simple sharp feature signal is ideal for them to probe some fundamental laws physics. Here we show that analyzing delay time between different frequencies, data can place stringent upper limits on rest mass photon. For at $z=0.492$, one...
The bulk Lorentz factor of the gamma-ray burst (GRB) ejecta (Γ0) is a key parameter to understanding GRB physics. Liang et al. have discovered correlation between Γ0 and isotropic γ-ray energy: Γ0∝E0.25γ, iso, 52. By including more GRBs with updated data methods derive Γ0, we confirm this obtain ≃ 91E0.29γ, Evaluating mean luminosities Lγ, iso in same sample, discover an even tighter 249L0.30γ, We propose interpretation later correlation. Invoking neutrino-cooled hyperaccretion disk around...
Abstract A hyperaccreting stellar-mass black hole (BH) has been proposed as the candidate central engine of gamma-ray bursts (GRBs). The rich observations GRBs by Fermi and Swift make it possible to constrain model comparing predictions against data. This paper is dedicated studying temporal evolution parameters for both prompt emission afterglow phases. We consider two jet-launching mechanisms, i.e., <?CDATA $\nu \bar{\nu }$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"...
The central engine of gamma-ray bursts (GRBs) is poorly constrained. There exist two main candidates: a fast-rotating black hole and rapidly spinning magnetar. Furthermore, the X-ray plateaus are widely accepted by energy injection into external shock. In this paper, we systematically analyze \emph{Swift}/XRT light curves 101 GRBs having plateau phases known redshifts (before May 2017). Since maximum budget ($\sim2\times10^{52}$ erg) exists for magnetars but not hole, provides good clue to...
Abstract A supermassive black hole can launch a relativistic jet when it violently disrupts star that passes too close. Such jetted tidal disruption events (TDEs) are rare and unique tools to investigate quiescent holes, physics, circumnuclear environments at high redshift. The newly discovered TDE AT2022cmc ( z ∼ 1.193), providing rich multiband (X-ray, UV, optical, submillimeter, radio) data, has been interpreted as the fourth on-axis TDE. In this work, we constrain medium (CNM) density...
Evolution characteristics of a Kerr black hole (BH) are investigated by considering the coexistence disc accretion with Blandford–Znajek process (the BZ process) and magnetic coupling BH surrounding (MC process). (i) The rate extracting energy from rotating in that MC expressed unified formula, which is derived using an improved equivalent circuit. (ii) mapping relation between angular coordinate on horizon radial given context general relativity conservation flux. (iii) power torque...
Recent observations and theoretical work on gamma-ray bursts favor the central engine model of a Kerr black hole (BH) surrounded by magnetized neutrino-dominated accretion flow (NDAF). The magnetic coupling between BH disk through large-scale closed field exerts torque transports rotational energy from to disk. We investigate properties NDAF with this torque. For rapid spinning BH, transfers enormous into inner There are two consequences: (1) luminosity neutrino annihilation is greatly...
Abstract Recently, a kilonova-associated gamma-ray burst (GRB 211211A), whose light curve consists of precursor (∼0.2 s), hard spiky emission (∼10 and soft long extended (∼40 has attracted great attention. Kilonova association could prove its merger origin, while the detection can be used to infer at least one highly magnetized neutron star (NS) being involved in merger. In this case, strong magnetic flux Φ is expected surround central engine GRB 211211A. Here we suggest that when large...
Abstract The Einstein Probe (EP) achieved its first detection and localization of a bright X-ray flare, EP240219a, on 2024 February 19, during commissioning phase. Subsequent targeted searches triggered by the EP240219a alert identified faint, untriggered gamma-ray burst (GRB) in archived data Fermi Gamma-ray Burst Monitor (GBM), Swift Alert Telescope (BAT), Insight-HXMT/HE. EP Wide-field (WXT) light curve reveals long duration approximately 160 s with slow decay, whereas Fermi/GBM shows...
Recently a hard X-ray transient event, Sw J1644+57, was discovered by the Swift satellite. It likely marks onset of relativistic jet from supermassive black hole, possibly triggered tidal disruption event. Another candidate in same category, J2058+05, also reported. The low event rate suggests that only small fraction TDEs launch jets. A common speculation is these rare events are related to rapidly spinning holes. We attribute launching Blandford-Znajek mechanism, and use available data...
A particularly interesting discovery in observations of GRB 121027A is that a giant X-ray bump detected by the Swift/X-Ray Telescope. The afterglow re-brightens sharply at ∼103 s after trigger more than two orders magnitude less 200 s. This lasts for 104 It quite different from typical flares. In this Letter we propose fall-back accretion model to interpret within context collapse massive star long-duration gamma-ray burst. required radius ∼3.5 × 1010 cm and mass ∼0.9–2.6 M☉ imply...
The X-ray plateau followed by a steep decay ("internal plateau") has been observed in both long and short gamma-ray burst (GRBs), implying millisecond magnetar operating some GRBs. sharp at the end of plateau, marking abrupt cessation central engine, considered as collapse supra-massive to black hole (BH) when it spins down. If "internal plateau" is indeed evidence natural expectation signature from new-born BH candidates. In this work, we find that GRB 070110 particular case, which shows...
Abstract The gamma-ray burst GRB 221009A, known as the “brightest of all time,” is closest energetic detected so far, with an energy E γ ,iso ∼ 10 55 erg. This study aims to assess its compatibility and luminosity distributions. Our analysis indicates that energy/luminosity function GRBs consistent across various redshift intervals, inclusion 221009A does not significantly impact at low redshifts. Additionally, our evaluation best-fitting result entire sample suggests expected number greater...
The X-ray transient source Sw J1644+57 recently discovered by Swift is believed to be triggered tidal disruption of a star rapidly spinning supermassive black hole (SMBH). For such events, the outer disk very likely misaligned with respect equatorial plane SMBH, since incoming before most has an inclined orbital plane. tilted subject Lense-Thirring torque, which tends twist and warp due Bardeen-Petterson effect. inner align SMBH spin, while region remain in stellar plane, transition zone...
Synchrotron self-Compton (SSC) scattering is an important emission mechanism in many astronomical sources, such as gamma-ray bursts (GRBs) and active galactic nuclei. We give a complete presentation of the analytical approximations for Compton synchrotron with both weak strong self-absorption. All possible orders characteristic spectral breaks (νa, νm νc) are studied. In self-absorption regime, i.e. νa < νc, electron energy distribution not modified by process. The shape SSC component...
ABSTRACT Supermassive black holes (SMBHs) can capture and tidally disrupt stars or substellar objects orbiting nearby. The detections of Sw J1644+57-like events suggest that at least some TDEs launch a relativistic jet beaming toward Earth. A natural expectation would be the existence with away from nearby TDE candidate IGR J12580+0134 provides new insights into phenomenon. Combining several constraints, we find event invokes 8−40 Jupiter mass object disrupted by <?CDATA $3\times...
The continued observations of Sw J1644+57 in X-ray and radio bands accumulated a rich data set to study the relativistic jet launched this tidal disruption event. light curve from 5-30 days presents two kinds quasi-periodic variations: 200 second oscillation (QPO) 2.7-day variation. latter has been interpreted by precessing near Bardeen-Petterson radius warped disk. Here we suggest that $\sim$ 200s QPO could be associated with second, narrower sweeping observer line-of-sight periodically,...
<title>Abstract</title> Gamma-ray bursts (GRBs), among the most energetic events in universe, are traditionally classified into long-duration GRBs, lasting over two seconds, and short-duration less than seconds<sup>1</sup> . Long GRBs typically associated with collapse of massive stars (Type II), while short arise from merger compact binary objects I) <sup>2–5</sup>. Due to their different origins, they exhibit distinct statistical properties observations, which serve as valuable criteria...