The Two-point Correlation Function of Gamma-Ray Bursts
Abstract
In this paper, we examine the spatial distribution of gamma-ray bursts (GRBs) using a sample of 373 objects. We subdivide the GRB data into two redshift intervals over the redshift range 0 < z < 6.7. We measure the two-point correlation function, ξ(r), of the GRBs. In determining the separation distance of the GRB pairs, we consider two representative cosmological models: a cold dark matter universe plus a cosmological constant Λ, with (Ωm, ΩΛ) = (0.28, 0.72), and an Einstein-de Sitter universe, with (Ωm, ΩΛ) = (1, 0). We find a z-decreasing correlation of the GRB distribution, which is in agreement with the predictions of the current structure formation theory. We fit a power-law model ξ (r)={(r/{r}0)}-γ to the measured ξ(r) and obtain an amplitude and slope of {r}0=1235.2+/- 342.6{h}-1 Mpc and γ = 0.80 ± 0.19, respectively (1σ confidence level), over the scales r = 200-104 h-1 Mpc. Our results provide a supplement to the measurement of matter correlation on large scales, while the matter distribution below 200 h-1 Mpc is usually described by the correlation function of galaxies.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 2015
- DOI:
- 10.1088/0004-637X/807/1/76
- arXiv:
- arXiv:1507.01319
- Bibcode:
- 2015ApJ...807...76L
- Keywords:
-
- cosmology: observations;
- gamma-ray burst: general;
- large-scale structure of universe;
- methods: statistical;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 25 pages, 7 figures, 3 tables