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Energy of the Most Extreme Gamma Rays

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Bibliographic Entry Result
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Standardized
Result
Pasachoff, Jay M. Physics. Illinois: Scott Foresman, 1990: 1168. "12 keV" 12 keV
Lerner, Rita and George L. Trigg. "Gamma Rays." Encyclopedia of Physics. New York: VCH, 1991: 425. "The energy of gamma rays emitted during the course of nuclear reactions, when these are initiated by low energy particles, can extend up to about 20 MeV." 20 MeV
Stecker, Floyd William. Cosmic Gamma Rays. Washington, DC: NASA, 1971: 3. "the nature of these interactions up to ~30 GeV" 30 GeV
Böttcher, Markus & Charles Dermer. High Energy Gamma Rays from Ultrahigh Energy Cosmic Ray Protons in Gamma Ray Bursts. APS/AAPT Joint Meeting. Columbus, OH: April 18-21, 1998. "It has recently been proposed that ultrahigh energy (> 10^19 eV) cosmic rays (UHECR) are accelerated by the blast
waves associated with GRBs.'
> 1019 eV
"Normalizing to the emission characteristics of GRB~970508, we predict \sim 10 MeV - 100 GeV fluxes at a level which may have been observed with EGRET from bright GRBs, and could be detected with the proposed GLAST experiment or with ground-based air Cherenkov telescopes having thresholds < several hundred GeV." 100 GeV
Rigden, John. "Gamma Rays." Macmillan Enyclopedia of Physics. New York: Simon & Schuster, 1996: 651. "which are very high energy photons (energies above 100,000 eV)" > 0.1 MeV

Gamma rays are a type of electromagnetic radiation. They have a shorter wavelength than x rays. Gamma rays are emitted from the nuclei of the atoms. Gamma rays can carry billions of electron volts of energy per photon and can pass through almost all types of matter, but lose energy after colliding with atoms. Sufficiently high-energy gamma ray photons can create matter in the form of matter-antimatter pairs.

The majority of numbers shown above are for the energy of gamma rays that are considered ordinary. The most extreme gamma rays are brought about cosmic ray bursts. Through the course of my research I found five different numbers for the energy. I was able to eliminate 3 numbers and I was left with two reasonable numbers for the energy of the most extreme gamma rays. The first number (12 keV) was way too small. The second number (20 MeV) was the energy of a gamma ray produced during a nuclear reaction. The third number (30 GeV) was one of the possible answers. The fifth entry (energies above 100,000 eV) is way too broad to be a possible answer. I think that the forth number was the best number. The energy of the most extreme gamma rays should range anywhere from 10 to 100 GeV (ten billion to one hundred billion electron-volts).

Jonathan Starr -- 1999