Classification of Swift's gamma-ray bursts

Abstract

Two classes of gamma-ray bursts have been identified in the BATSE catalogs characterized by durations shorter and longer than about 2 seconds. There are, however, some indications for the existence of a third class. Swift satellite detectors have different spectral sensitivity than pre-Swift ones for gamma-ray bursts. Therefore, it is worth to reanalyze the durations and their distribution. We analyze, the maximum likelihood estimation, the bursts duration distribution, published in The First BAT Catalog, whether it contains two, three or more groups. The three log-normal fit is significantly (99.54% probability) better than the two for the duration distribution. Monte-Carlo simulations also confirm this probability (99.2%). Similarly, in previous results we found that the fourth component is not needed. The relative frequencies of the distribution of the groups are 7% short 35% intermediate and 58% long. Although the relative frequencies of the groups are different than in the BATSE GRB sample, the difference in the instrument spectral sensitivities can explain this bias on a natural way. This means theoretical models may be needed to explain three different type of gamma-ray bursts.

Accepted in AA, added bibliography

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Cited by in corpus (54)

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• Short vs. Long Gamma-Ray Bursts: A Comprehensive Study of Energetics and Prompt Gamma-Ray Correlations
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• Statistical Study of Observed and Intrinsic Durations among BATSE and Swift/BAT GRBs
• Classification of Gamma-Ray Burst durations using robust model-comparison techniques
• A comparison of the gamma-ray bursts detected by BATSE and Swift
• Analysis of Fermi gamma-ray burst duration distribution
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• The duration distribution of Swift Gamma-Ray Bursts
• A Comprehensive Power Spectral Density Analysis of Astronomical Time Series. II. The Swift/BAT Long Gamma-Ray Bursts
• Search for Gamma-Ray Burst Classes with the RHESSI Satellite
• Gaussian-mixture-model-based cluster analysis of gamma-ray bursts in the BATSE catalog
• Testing Isotropic Universe Using the Gamma-Ray Burst Data of Fermi / GBM
• A search for pulsations in short gamma-ray bursts to constrain their progenitors
• Properties of Short Gamma-Ray Burst Pulses from A BATSE TTE GRB Pulse Catalog
• Testing the anisotropy in the angular distribution of $Fermi$/GBM gamma-ray bursts
• Some statistical remarks on the Giant GRB Ring
• Distributions of Pseudo-Redshifts and Durations (Observed and Intrinsic) of Fermi GRBs
• On the limit between short and long GRBs
• Classifying GRB170817A / GW170817 in a Fermi duration - hardness plane
• Distinction of groups of gamma-ray bursts in the BATSE catalog through fuzzy clustering
• GRB 140102A: Insight into Prompt Spectral Evolution and Early Optical Afterglow Emission
• Multivariate analysis of BATSE gamma-ray burst properties using skewed distributions
• Two Dimensional Clustering of Gamma-Ray Bursts using durations and hardness
• Two Dimensional Classification of the Swift/BAT GRBs
• Analysis of the observed and intrinsic durations of gamma-ray bursts with known redshift
• Analysis of the observed and intrinsic durations of $Swift$/BAT gamma-ray bursts
• Cosmological effects on the observed flux and fluence distributions of gamma-ray bursts: Are the most distant bursts in general the faintest ones?
• On the Connection of Gamma-Ray Bursts and X-Ray Flashes in the BATSE and RHESSI Databases
• GRB 070518: A Gamma-ray Burst with Optically Dim Luminosity
• Distinguishing short and long $Fermi$ gamma-ray bursts
• Update on the GRB universal scaling E${}_{\mathrm{X},\mathrm{iso}}$-E${}_{\gamma ,\mathrm{iso}}$-E${}_{\mathrm{pk}}$ with ten years of $Swift$ data
• On the Subclasses in Swift Long Gamma-Ray Bursts: A Clue to Different Central Engines
• GRB Optical and X-ray Plateau Properties Classifier Using Unsupervised Machine Learning
• Distribution of Si II $\lambda$6355 Velocities of Type Ia Supernovae and Implications for Asymmetric Explosions
• Graph-based clustering of gamma-ray bursts
• Multidimensional analysis of Fermi GBM gamma-ray bursts
• Revisiting the Formation Rate and the Redshift Distribution of LGRBs
• Can the Cosmological Dilation Explain the Skewness in the Gamma-Ray Burst Duration Distribution?
• Distribution of gamma-ray bursts on the t90-hardness ratio plane and their classification revisited
• Studying the variability of the X-ray spectral parameters of high-redshift GRBs' afterglows
• How does the shape of gamma-ray bursts' pulses affect the duration distribution?
• Some statistical remarks on GRBs jointly detected by Fermi and Swift satellites
• Generalized Linear Models of T${}_{90}$-T${}_{50}$ relation to classify GRBs
• Search for Cosmological time dilation from Gamma-Ray Bursts -- A 2021 status update