Gamma-Ray Bursts: Temporal Scales and the Bulk Lorentz Factor

Abstract

For a sample of Swift and Fermi GRBs, we show that the minimum variability timescale and the spectral lag of the prompt emission is related to the bulk Lorentz factor in a complex manner: For small $\Gamma$'s, the variability timescale exhibits a shallow (plateau) region. For large $\Gamma$'s, the variability timescale declines steeply as a function of $\Gamma$ ($\delta T\propto {\Gamma }^{-4.05\pm 0.64}$). Evidence is also presented for an intriguing correlation between the peak times, t${}_p$, of the afterglow emission and the prompt emission variability timescale.

arXiv commentAccepted for publication in ApJ

References in corpus (36)

• Gamma-Ray Bursts and the Fireball Model
• Gamma-Ray Bursts
• Jets in GRBs
• Can internal shocks produce the variability in GRBs?
• Lower Limits on Lorentz Factors in Gamma Ray Bursts
• Fermi Observations of GRB 090902B: A Distinct Spectral Component in the Prompt and Delayed Emission
• Analytic Light-Curves of Gamma-Ray Burst Afterglows: Homogeneous versus Wind External Media
• Fermi Observations of GRB 090510: A Short Hard Gamma-Ray Burst with an Additional, Hard Power-Law Component from 10 keV to GeV Energies
• The First Fermi LAT Gamma-Ray Burst Catalog
• Fermi-LAT Observations of the Gamma-ray Burst GRB 130427A
• Expanding Relativistic Shells and Gamma-Ray Burst Temporal Structure
• Constraining GRB Initial Lorentz Factor with the Afterglow Onset Feature and Discovery of a Tight Gamma_0-E_iso Correlation
• External forward shock origin of high energy emission for three GRBs detected by Fermi
• GeV emission from Gamma Ray Bursts: a radiative fireball?
• Efficiency of Magnetic to Kinetic Energy Conversion in a Monopole Magnetosphere
• A new method of determining the initial size and Lorentz factor of gamma-ray burst fireballs using a thermal emission component
• Gamma Ray Bursts in the comoving frame
• Magnetohydrodynamic Simulations of Gamma-Ray Burst Jets: Beyond the Progenitor Star
• GRB 130427A: a Nearby Ordinary Monster
• Lorentz Factor-Isotropic Luminosity/Energy Correlations of GRBS and Their Interpretation
• The Lag-Luminosity Relation in the GRB Source-Frame: An Investigation with Swift BAT Bursts
• Spectral lags and the energy dependence of pulse width in gamma-ray bursts: contributions from the relativistic curvature effect
• Minimum Variability Time Scales of Long and Short GRBs
• Uncovering the Intrinsic Variability of Gamma-ray Bursts
• Rarefaction acceleration of ultrarelativistic magnetized jets in gamma-ray burst sources
• Characteristics of profiles of gamma-ray burst pulses associated with the Doppler effect of fireballs
• On the Kinematic Origin of the Luminosity-Pulse Lag Relationship in Gamma-ray Bursts
• Spectral Lags of Gamma-Ray Burst From Ginga and BATSE
• Lorentz Factor Constraint from the very early external shock of the gamma-ray burst ejecta
• Spectral lags caused by the Doppler effect of fireballs
• On Spectral and Temporal Variability in Blazars and Gamma Ray Bursts
• Estimates for Lorentz factors of gamma-ray bursts from early optical afterglow observations
• Diagnosing GRB Prompt Emission Site with Spectral Cut-Off Energy
• The Minimum Variability Time Scale and its Relation to Pulse Profiles of Fermi GRBs
• Luminosity correlations for gamma-ray bursts and implications for their prompt and afterglow emission mechanisms
• A New Correlation Between GRB X-Ray Flares And The Prompt Emission

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