A Remarkable Angular Distribution of the Intermediate Subclass of Gamma-Ray Bursts

Abstract

In the article a test is developed, which allows to test the null-hypothesis of the intrinsic randomness in the angular distribution of gamma-ray bursts collected at the Current BATSE Catalog. The method is a modified version of the well-known counts-in-cells test, and fully eliminates the non-uniform sky-exposure function of BATSE instrument. Applying this method to the case of all gamma-ray bursts no intrinsic non-randomness is found. The test also did not find intrinsic non-randomnesses for the short and long gamma-ray bursts, respectively. On the other hand, using the method to the new intermediate subclass of gamma-ray bursts, the null-hypothesis of the intrinsic randomness for 181 intermediate gamma-ray bursts is rejected on the 96.4% confidence level. Taking 92 dimmer bursts from this subclass itself, we obtain the surprising result: This "dim" subclass of the intermediate subclass has an intrinsic non-randomness on the 99.3% confidence level. On the other hand, the 89 "bright" bursts show no intrinsic non-randomness.

14 pages, 2 figures, Accepted for publication in Astrophysical Journal, typo changes

References in corpus (10)

• Three types of gamma-ray bursts
• A 3rd Class of Gamma Ray Bursts?
• BATSE Observations of the Large-Scale Isotropy of Gamma-Ray Bursts
• The Angular Power Spectrum of BATSE 3B Gamma-Ray Burst
• An intrinsic anisotropy in the angular distribution of gamma-ray bursts
• Improved limits on gamma ray burst repetition
• Do Gamma-Ray Burst Sources Repeat?
• Are The Four Gamma-Ray Bursts of 1996 October 27-29 Due to Repetition of a Single Source?
• A Constraint on the Distance Scale to Cosmological Gamma--Ray Bursts
• GRB Repetition Limits from Current BATSE Observations

Cited by in corpus (30)

• The Physics of Gamma-Ray Bursts
• Gamma-Ray Bursts
• Gamma-Ray Bursts: Progress, Problems & Prospects
• A new definition of the intermediate group of gamma-ray bursts
• Detailed Classification of Swift's Gamma-Ray Bursts
• Further Study of the Gamma-Ray Bursts Duration Distribution
• Possible structure in the GRB sky distribution at redshift two
• Classification of Swift's gamma-ray bursts
• A giant ring-like structure at 0.78<z<0.86 displayed by GRBs
• New data support the existence of the Hercules-Corona Borealis Great Wall
• 'On the difference between the short and long gamma-ray bursts'
• Gamma Ray Burst Prompt correlations
• Statistical Study of Observed and Intrinsic Durations among BATSE and Swift/BAT GRBs
• Testing the Randomness in the Sky-Distribution of Gamma-Ray Bursts
• Searching for differences in Swift's intermediate GRBs
• Testing Isotropic Universe Using the Gamma-Ray Burst Data of Fermi / GBM
• The clustering of gamma-ray bursts in the Hercules-Corona Borealis Great Wall: the largest structure in the Universe?
• Investigation of Redshift- and Duration-Dependent Clustering of Gamma-ray Bursts
• Revisiting the statistical isotropy of GRB sky distribution
• Some statistical remarks on the Giant GRB Ring
• Testing the anisotropy in the angular distribution of $Fermi$/GBM gamma-ray bursts
• Gamma photometric redshifts for long gamma-ray bursts
• Update on Testing the Isotropy of the Properties of Gamma-Ray Bursts
• An Oppositeness in the Cosmology: Distribution of the Gamma-Ray Bursts and the Cosmological Principle
• Anisotropy in the angular distribution of the long gamma-ray bursts?
• Distinguishing short and long $Fermi$ gamma-ray bursts
• Does the GRB Duration Depend on Redshift?
• The Two-Point Correlation Function of Gamma-ray Bursts
• Studying the variability of the X-ray spectral parameters of high-redshift GRBs' afterglows
• Scanning the Universe for Large-Scale Structures using Gamma-Ray Bursts