re gamma ray bursters how energetic could they be in article rgvjsinnbhq senator bedfellow mit edu jfc athena mit edu john f carr writes if gamma ray bursters are extragalactic would absorption from the galaxy be expected how transparent is the galactic core to gamma rays how much energy does a burster put out i know energy depends on distance which is unknown an answer of the form x ergs per megaparsec is ok john carr jfc athena mit edu i had to turn to one of my problem sets that i did in class for this little problem i don t have a calculator but i do have the problem set that we did not too long ago so i ll use that and hope it s what you wanted this is a highly simplified problem with a very simple burst bursts are usually more complex than this example i will use here our burst has a peak flux of e ergs cm sec and a duration of seconds during the frst second of the burst and the last seconds its flux is half of the peak flux it s flux is the peak flux the rest of the time assume that the background flux is e erg cm sec then we had to find the integrated luminosity of the burst for several different spheres r pc oort cloud radius r pc at the edge of the galaxy r pc or the edge of the galactic corona and lastly at a r mpc we integrated the flux over all time to find the fluence then used the old standby formula luminosity pi r fpeak for a radius of pc we found an l around erg sec pretty energetic for close by for the coronal model we found around erg sec and lastly for the cosmological model an l that s what you d call moderately energetic i d say any suggestions about what could put out that much energy in one second jeremy
