2014/06/27 by Lixiong Gan, Yuan-Chuan Zou, Gan, Lixiong +3
Physics and Astronomy · #FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #astro-ph.HE
paper · pdf · doi:10.48550/arxiv.1406.7085
9 pages, 2 figures
arxiv created 2014/06/27 · arxiv updated 2014/06/30
Anomalies of the cosmic microwave background (CMB) maps have been widely acquainted nowadays from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite to the Planck satellite. One of the anomalies is a multipole alignment from l=2 to l=5. In our work, we investigate the angular distribution of gamma-ray bursts (GRBs) to find whether there is the same anomaly of GRB as CMB. We perform spherical harmonics expansion on GRB samples to derive coefficients of a few first terms of the expansion terms and find that there is rough multipole alignment from l=2 to l=4 while the dipole and l=5 multipole is in a distant direction, and that the quadrupole is obviously planar and the other ones are normal.