Kavli Affiliate: Vahe Petrosian
| First 5 Authors: Sujay Champati, Sujay Champati, , ,
| Summary:
We investigate the cosmological evolution of the luminosity and redshift of
FRBs. As is the case for all extragalactic sources, we are dealing with data
that are truncated by observational selection effects, the most important being
the flux limit, which introduces the so-called Eddington-Malmquist bias. In
addition, for FRBs, there is a significant uncertainty in the redshifts
obtained from the observed dispersion measures (DMs). To correct for the
truncation we use the non-parametric, non-binning Efron-Petrosian and
Lynden-Bell methods, which give unbiased distributions of luminosities and
redshifts and their cosmological evolution. To quantify the redshift
uncertainty, we use a data set which accounts for uncertainties of contribution
to the DM of the host galaxy, and DM uncertainties due to fluctuation in the
intergalactic medium. This data, in addition to a mean redshift, gives the
one-sigma errors. We construct three samples with lower, mean, and upper
redshifts and apply the above methods to each. For the three samples, we find
similar (1) $sim 3sigma$ evidence for luminosity evolution, (2) a luminosity
function that can be fit by a simple broken power law, and (3) a comoving
density formation rate that decreases rapidly with redshift unlike the cosmic
star formation rate (SFR). This rate is similar to that of short gamma-ray
bursts, which are believed to result from compact star mergers with a formation
rate delayed relative to the SFR. This may further support the hypothesis that
magnetars are the progenitors of FRBs.
| Search Query: ArXiv Query: search_query=au:”Vahe Petrosian”&id_list=&start=0&max_results=3