Gravitational Lensing Limits On The Average Redshift Of Gamma Ray Bursts From Evolving Galaxies
نویسنده
چکیده
The nondetection of multiple images in the BATSE 4B catalog implies an upper limit to average redshift < z > of gamma ray bursts (GRBs). Here we calculate an upper limit to < z >, independent of the physical model for GRBs, using a filled approximation to compute the lensing rate for GRBs at high z for a variety of cosmologies. The upper limit on < z > depends directly on the cosmological parameters Ω and Λ. The other factor which can change the average redshift of GRBs is the evolution of the lensing galaxies. We find that merging of lensing galaxies puts the GRBs at higher redshifts as compare to nonevolving model of galaxies. The uncertainty in the average redshift of E–mail : [email protected] E–mail : [email protected] E–mail : [email protected] E–mail : [email protected]
منابع مشابه
Gravitational Lensing Bound On The Average Redshift Of Gamma Ray Bursts In Models With Evolving Lenses
The non detection of multiple images due to gravitational lensing in the BATSE 4B catalog implies an upper limit to the average redshift < z > of Gamma Ray Bursts (GRBs). Here we calculate an upper limit to < z >, independent of the physical model for GRBs, using a filled approximation to compute the lensing rate for GRBs at high z for a variety of cosmologies. The upper limit on < z > depends ...
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