The Astrophysical Journal
The American Astronomical Society
We compute the angular power spectrum C1 from the BATSE 3B catalog of 1122 gamma-ray burts and find no evidence of clustering on any scale. These constraints bridge the entire range from samall scales (which probe source clustering and burst repetition) to the largest scales (which constrain possible anisotropies from the Galactic hal or from nearby cosmological large-scale structures). We develop an analysis tecnique that takes the angular position errors into account. For specific clustering or repetition models, strong upper limits can be obtained down to scales l ~ 30, corresponding to abou couple of degrees on the sky. The minimum-variance burst weighting that we employ to visulaized graphically as an all-sky map in which each burts is smeared out by an amount correponding to its position uncertainity. We also present separate bandpas-filtered sky maps for the quadrupole term and for the multipole ranges l = 3-10 and l - 11-30, so that the fluctuations on different angular scales can be inspected separately for visual features such as localized "hot spots" or structures aligned wit the Galactic plane. These filtered maps reveal no apparent deviations from isotropy.
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