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View Full Version : Red Shifted Gammer Ray Bursts?



Peter Fagan
2008-Jul-29, 07:34 PM
Why do we detect Gammer Ray Bursts from the most distant galaxys and they still reach us as Gammer rays? Why are they not Red Shifted to X-rays or Ultra Violet? Sorry if I sound dumb im just a window cleaner and not a scientist lol. can anyone help?

peteshimmon
2008-Jul-30, 05:38 PM
No not dumb at all but a very acute question!
The photon energies in bursts tend to range
from X-ray levels to higher. Gamma ray bursts
has become a general term for any burst and is
inaccurate.

I have yet to see in the popular mag I see
any plot of energies in bursts against the
claimed redshifts. They must exist.

Should have posted in questions!

Sovieto
2008-Jul-30, 10:11 PM
Aren't gamma rays, x-rays, and other waves, just names to record their frequency and wavelength? A red shift shouldn't change that.

Slardybardfast
2008-Jul-31, 12:40 AM
Gamma rays are electromagnetic waves just like visible light and they will be red shifted when they originate in objects that are cosmologically distant from us. The observed frequency of a gamma ray will depend on the amount of red shift. See the URL below for methods of calculation of observed red shift.

However, since gamma rays are at the upper end of the frequency spectrum (with no upper limit defined), even red shifted the observed photon may be a gamma ray.


http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/reldop3.html#c3

Slardy

Peter Fagan
2008-Jul-31, 06:33 PM
Thanks Pete and Slardy.