skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: What Can We Learn about GRB from the Variability Timescale Related Correlations?

Abstract

Recently, two empirical correlations related to the minimum variability timescale (MTS) of the light curves are discovered in gamma-ray bursts (GRBs). One is the anti-correlation between MTS and Lorentz factor Γ, and the other is the anti-correlation between the MTS and gamma-ray luminosity L {sub γ}. Both of the two correlations might be used to explore the activity of the central engine of GRBs. In this paper, we try to understand these empirical correlations by combining two popular black hole central engine models (namely, the Blandford and Znajek mechanism (BZ) and the neutrino-dominated accretion flow (NDAF)). By taking the MTS as the timescale of viscous instability of the NDAF, we find that these correlations favor the scenario in which the jet is driven by the BZ mechanism.

Authors:
; ;  [1]
  1. School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China)
Publication Date:
OSTI Identifier:
22661185
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 838; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCRETION DISKS; BLACK HOLES; CORRELATIONS; COSMIC GAMMA BURSTS; GAMMA RADIATION; INSTABILITY; LUMINOSITY; MAGNETIC FIELDS; NEUTRINOS; STARS; VISIBLE RADIATION

Citation Formats

Xie, Wei, Lei, Wei-Hua, and Wang, Ding-Xiong, E-mail: leiwh@hust.edu.cn. What Can We Learn about GRB from the Variability Timescale Related Correlations?. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA6718.
Xie, Wei, Lei, Wei-Hua, & Wang, Ding-Xiong, E-mail: leiwh@hust.edu.cn. What Can We Learn about GRB from the Variability Timescale Related Correlations?. United States. doi:10.3847/1538-4357/AA6718.
Xie, Wei, Lei, Wei-Hua, and Wang, Ding-Xiong, E-mail: leiwh@hust.edu.cn. Sat . "What Can We Learn about GRB from the Variability Timescale Related Correlations?". United States. doi:10.3847/1538-4357/AA6718.
@article{osti_22661185,
title = {What Can We Learn about GRB from the Variability Timescale Related Correlations?},
author = {Xie, Wei and Lei, Wei-Hua and Wang, Ding-Xiong, E-mail: leiwh@hust.edu.cn},
abstractNote = {Recently, two empirical correlations related to the minimum variability timescale (MTS) of the light curves are discovered in gamma-ray bursts (GRBs). One is the anti-correlation between MTS and Lorentz factor Γ, and the other is the anti-correlation between the MTS and gamma-ray luminosity L {sub γ}. Both of the two correlations might be used to explore the activity of the central engine of GRBs. In this paper, we try to understand these empirical correlations by combining two popular black hole central engine models (namely, the Blandford and Znajek mechanism (BZ) and the neutrino-dominated accretion flow (NDAF)). By taking the MTS as the timescale of viscous instability of the NDAF, we find that these correlations favor the scenario in which the jet is driven by the BZ mechanism.},
doi = {10.3847/1538-4357/AA6718},
journal = {Astrophysical Journal},
number = 2,
volume = 838,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
  • The formalism recently introduced in hadronic intermittency is used to understand the dynamics of one-dimensional fractal sets. We examine the translation invariance, factorial and cumulant moments, and the fractal dimensions of the phase space as the nonlinearity of the sets is changed in a broad range from intermittent to chaotic. We show that the dynamical content of the sets is strongly interwoven with the magnitude of the fractal dimensions of the phase-space correlations. We simulate events by properly transforming the logistic map so that relevant density histograms of hadronic particle distributions are qualitatively produced. We use this as a toymore » model to understand the rapidity phase-space behavior of these distributions. By studying the fractal dimensions of these models we show that the hadronic data show very weak intermittency in the rapidity phase space.« less
  • We have used recent data from the CERN and SLAC to extract information about nucleon spin structure. We find that the SMC proton data on {integral}{sub 0}{sup 1}g{sub 1}{sup p}dx, the E142 neutron data on {integral}{sub 0}{sup 1}g{sub 1}{sup n}dx, and the deuteron data from the SMC and E143 give different results for fractions of the spin carried by each of the constituents. These appear to lead to two different and incompatible models for the polarized strange sea. The polarized gluon distribution occurring in the gluon anomaly does not have to be large in order to be consistent with eithermore » set of experimental data. However, it appears that the discrepancies in the implications of these data cannot be resolved with any simple theoretical arguments. We conclude that more experiments must be performed in order to adequately determine the fraction of spin carried by each of the nucleon constituents. {copyright} {ital 1997} {ital The American Physical Society}« less
  • Electrode materials for Li-ion batteries should combine electronic and ionic conductivity, structural integrity, and safe operation over thousands of lithium insertion and removal cycles. The quest for higher energy density calls for better understanding of the redox processes, charge and mass transfer occurring upon battery operation. A number of techniques have been used to characterize long-range and local structure, electronic and ionic transport in bulk of active materials and at interfaces, with an ongoing move toward in situ techniques determining the changes as they happen. This paper reviews several representative examples of using magnetic properties toward understanding of Li-ion batterymore » materials with a notion to highlight the intimate connection between the magnetism, electronic and atomic structure of solids, and to demonstrate how this connection has been used to reveal the fine electronic and atomic details related to the electrochemical performance of the battery materials.« less
  • Electrode materials for Li-ion batteries should combine electronic and ionic conductivity, structural integrity, and safe operation over thousands of lithium insertion and removal cycles. The quest for higher energy density calls for better understanding of the redox processes, charge and mass transfer occurring upon battery operation. A number of techniques have been used to characterize long-range and local structure, electronic and ionic transport in bulk of active materials and at interfaces, with an ongoing move toward in situ techniques determining the changes as they happen. This paper reviews several representative examples of using magnetic properties toward understanding of Li-ion batterymore » materials with a notion to highlight the intimate connection between the magnetism, electronic and atomic structure of solids, and to demonstrate how this connection has been used to reveal the fine electronic and atomic details related to the electrochemical performance of the battery materials.« less