X-ray flare candidates in short gamma-ray bursts

Abstract

We present the first systematic study of X-ray flare candidates in short gamma-ray bursts (SGRBs) exploiting the large 6-year Swift database with the aim to constrain the physical nature of such fluctuations. We find that flare candidates appear in different types of SGRB host galaxy environments and show no clear correlation with the X-ray afterglow lifetime; flare candidates are detected both in SGRBs with a bright extended emission in the soft gamma-rays and in SGRBs which do not show such component. We furthermore show that SGRB X-ray flare candidates only partially share the set of observational properties of long GRB (LGRB) flares. In particular,the main parameter driving the duration evolution of X-ray variability episodes in both classes is found to be the elapsed time from the explosion, with very limited dependence on the different progenitors, environments, central engine life-times, prompt variability time-scales and energy budgets. On the contrary, SGRB flare candidates significantly differ from LGRB flares in terms of peak luminosity, isotropic energy, flare-to-prompt luminosity ratio and relative variability flux. However, these differences disappear when the central engine time-scales and energy budget are accounted for, suggesting that (i) flare candidates and prompt pulses in SGRBs likely have a common origin; (ii) similar dissipation and/or emission mechanisms are responsible for the prompt and flare emission in long and short GRBs, with SGRBs being less energetic albeit faster evolving versions of the long class. Finally, we show that in strict analogy to the SGRB prompt emission, flares candidates fall off the lag-luminosity relation defined by LGRBs, thus strengthening the SGRB flare-prompt pulse connection.

19 pages, 16 figures, MNRAS accepted

References in corpus (17)

• Long gamma-ray bursts and core-collapse supernovae have different environments
• The missing link: Merging neutron stars naturally produce jet-like structures and can power short Gamma-Ray Bursts
• Fallback accretion in the aftermath of a compact binary merger
• Short versus Long Gamma-Ray Bursts: spectra, energetics, and luminosities
• Precursors of short gamma-ray bursts
• A Comparison of the Afterglows of Short- and Long-Duration Gamma-Ray Bursts
• Phase transitions and He-synthesis driven winds in neutrino cooled accretion disks: prospects for late flares in short gamma-ray bursts
• The X-ray afterglow of the short gamma ray burst 050724
• Peak energy of the prompt emission of long Gamma Ray Bursts vs their fluence and peak flux
• Correlations Between Lag, Luminosity, and Duration in Gamma-ray Burst Pulses
• The optical afterglows and host galaxies of three short/hard gamma-ray bursts
• Flares in GRB afterglows from delayed magnetic dissipation
• The Optical Afterglow and z=0.92 Early-type Host Galaxy of the Short GRB 100117A
• Multicolor observations of the afterglow of the short/hard GRB 050724
• Heterogeneity in Short Gamma-ray Bursts
• Swift multi-wavelength observations of the bright flaring burst GRB051117A
• Nonthermal Synchrotron Radiation from Gamma Ray Burst External Shocks and the X-ray Flares Observed with Swift

Cited by in corpus (53)

• Short-Duration Gamma-Ray Bursts
• A Decade of Short-duration Gamma-ray Burst Broad-band Afterglows: Energetics, Circumburst Densities, and Jet Opening Angles
• Signatures of magnetar central engines in short GRB lightcurves
• The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/VIRGO GW170817. V. Rising X-ray Emission from an Off-Axis Jet
• Formation of Stable Magnetars from Binary Neutron Star Mergers
• Short GRB 130603B: Discovery of a jet break in the optical and radio afterglows, and a mysterious late-time X-ray excess
• Multi-messenger picture of compact binary mergers
• The prompt-afterglow connection in Gamma-Ray Bursts: a comprehensive statistical analysis of Swift X-ray light-curves
• First Multimessenger Observations of a Neutron Star Merger
• High-Energy Neutrino Emission from Short Gamma-Ray Bursts: Prospects for Coincident Detection with Gravitational Waves
• Self-organized criticality in X-ray flares of gamma-ray burst afterglows
• Comprehensive study of the X-ray flares from gamma-ray bursts observed by Swift
• Energy Injection in Gamma-ray Burst Afterglows
• Gamma-Ray Burst Science in the Era of the Cherenkov Telescope Array
• Searching for magnetar powered merger-novae from short GRBs
• Double Neutron Star Mergers and Short Gamma-Ray Bursts: Long-Lasting High-Energy Signatures and Remnant Dichotomy
• New measurements of ${\Omega }_m$ from gamma-ray bursts
• Radio Constraints on Long-Lived Magnetar Remnants in Short Gamma-Ray Bursts
• Bimodal Long-Lasting Components in Short Gamma-Ray Bursts: Promising Electromagnetic Counterparts to Neutron Star Binary Mergers
• A universal scaling for short and long gamma-ray bursts: E_{X,iso}-E_{gamma,iso}-E_{pk}
• Long-Lasting Black-Hole Jets in Short Gamma-Ray Bursts
• The Transient Gravitational-Wave Sky
• Accretion and outflow from a magnetized, neutrino cooled torus around the gamma ray burst central engine
• The Afterglow and Environment of the Short GRB111117A
• GRB 120711A: an intense INTEGRAL burst with long-lasting soft gamma-ray emission and a powerful optical flash
• Gamma Ray Bursts with Extended Emission Observed with BATSE
• Evidence for New Relations between Gamma Ray Burst Prompt and X-ray Afterglow Emission from 9 Years of Swift
• Statistical Distributions of Optical Flares from Gamma-Ray Bursts
• A VLA Study of High-redshift GRBs II - The Complex Radio Afterglow of GRB 140304A: Shell Collisions and Two Reverse Shocks
• Statistical analyses on the energies of X-ray plateaus and flares in gamma-ray bursts
• Gamma-ray burst afterglow blast waves
• Flares in Gamma Ray Bursts: Disc Fragmentation and Evolution
• Precessing magnetars as central engines in short gamma-ray bursts
• Analysis of GRB 080319B and GRB 050904 within the fireshell model: evidence for a broader spectral energy distribution
• Fallback accretion on to a newborn magnetar: long GRBs with giant X-ray flares
• Limits on optical polarization during the prompt phase of GRB 140430A
• The origin of the plateau and late rebrightening in the afterglow of GRB 120326A
• General Relativistic Simulations of Accretion Induced Collapse of Neutron Stars to Black Holes
• Prospects for multi-messenger extended emission from core-collapse supernovae in the Local Universe
• Update on the GRB universal scaling E${}_{\mathrm{X},\mathrm{iso}}$-E${}_{\gamma ,\mathrm{iso}}$-E${}_{\mathrm{pk}}$ with ten years of $Swift$ data
• Modelling the prompt optical emission of GRB 180325A: the evolution of a spike from the optical to gamma-rays
• Properties of Short GRB Pulses in the Fourth BATSE Catalog: Implications for Structure and Evolution of the Jetted Outflows
• Variability in Short Gamma-ray Bursts: Gravitationally Unstable Tidal Tails
• Scale invariance in X-ray flares of gamma-ray bursts
• Self Organized Criticality in an one dimensional magnetized grid. Application to GRB X-ray afterglows
• Central Engine-Powered Bright X-ray Flares in Short Gamma-Ray Bursts: A Hint of Black Hole-Neutron Star Merger?
• LOFAR detectability of prompt low-frequency radio emission during gamma-ray burst X-ray flares
• High time resolution search for prompt radio emission from the long GRB 210419A with the Murchison Widefield Array
• The evolution effects of radius and moment of inertia for rapidly rotating neutron stars
• An unusual transient following the short GRB 071227
• High-energy emissions from neutron star mergers
• The long-lasting optical afterglow plateau of short burst GRB 130912A
• A lower occurrence rate of bright X-ray flares in SN-GRBs than $z<1$ GRBs: evidence of energy partitions?