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تسجيل مستخدم جديدLensing by primordial black holes: constraints from gravitational wave observations
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Primordial black holes (PBHs) have been proposed to explain at least a portion of dark matter. Observations have put strong constraints on PBHs in terms of the fraction of dark matter which they can represent, $f_{rm PBH}$, across a wide mass range -- apart from the stellar-mass range of $20M_odotlesssim M_{rm PBH}lesssim 100M_odot$. In this paper, we explore the possibility that such PBHs could serve as point-mass lenses capable of altering the gravitational-wave (GW) signals observed from binary black hole (BBH) mergers along their line-of-sight. We find that careful GW data analysis could verify the existence of such PBHs based on the $fitting~factor$ and odds ratio analyses. When such a lensed GW signal is detected, we expect to be able to measure the redshifted mass of the lens with a relative error $Delta M_{rm PBH}/M_{rm PBH}lesssim0.3$. If no such lensed GW events were detected despite the operation of sensitive GW detectors accumulating large numbers of BBH mergers, it would translate into a stringent constraint of $f_{rm PBH}lesssim 10^{-2}-10^{-5}$ for PBHs with a mass larger than $sim10M_odot$ by the Einstein Telescope after one year of running, and $f_{rm PBH}lesssim 0.2$ for PBHs with mass greater than $sim 50M_odot$ for advanced LIGO after ten years of running.
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