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Limits on the cosmological abundance of supermassive compact objects from a millilensing search in gamma-ray burst data

Robert J. Nemiroff·Gabriela F. Marani·Jay P. Norris·Jerry T. Bonnell
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Abstract

A new search for the gravitational lens effects of a significant cosmological density of supermassive compact objects (SCOs) on gamma-ray bursts has yielded a null result. We inspected the timing data of 774 BATSE-triggered GRBs for evidence of millilensing: repeated peaks similar in light-curve shape and spectra. Our null detection leads us to conclude that, in all candidate universes simulated, $Ω_{SCO} < 0.1$ is favored for $10^5 < M_{SCO}/M_{\odot} < 10^9$, while in some universes and mass ranges the density limits are as much as 10 times lower. Therefore, a cosmologically significant population of SCOs near globular cluster mass neither came out of the primordial universe, nor condensed at recombination.

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Robert J. Nemiroff, Gabriela F. Marani, Jay P. Norris, Jerry T. Bonnell. 2001-01-26. Limits on the cosmological abundance of supermassive compact objects from a millilensing search in gamma-ray burst data. https://doi.org/10.1103/physrevlett.86.580

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