Does a gamma ray ray carry enough information to prove its source?
depends, it cant bend in magnetic nor electric fields, so the you can extrapolate its direction. i.e you can know from what postition in space it come from.
Before Chandra most X ray telescopes had pretty poor angular resolution so you had to do something like "there's an X ray source in the same bit of the sky as the Crab Nebula, X ray sources have to be pretty energetic so therefore the Crab must be the source of the X rays"
chandra has about the same resolution as the best optical ground based telescopes.
If one is referring to cosmological origins, for a single gamma photon, not necessarily. One usually relies upon the direction from which the gamma ray is received in order to determine is source, as indicated by mgb_phys.
Apart from the direction i guess its energy is clue as to its origins, if so do we have an idea of what phenomenon produces an gamma ray of X energy?
you mean X-rays ?
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