Gamma rays may have a subjective definition.You can say that Gamma Rays are photons emitted by state transitions of the nucleus and X-Rays are photons that comes from electrons. X-Ray machines emits what would be otherwise consider gamma rays, around 140KeV. For example, http://en.wikipedia.org/wiki/Technetium-99m
The gamma ray can have a small wavelength such that it could almost fit in the range of visible light, such as http://en.wikipedia.org/wiki/Isotopes_of_thorium#Thorium-229m If you consider a gamma ray as photons originated by decays of excited decays of the nucleus, you can have wave lengths near the visible spectrum, 2011/10/29 Peter Heckert <peter.heck...@arcor.de> > Am 29.10.2011 16:32, schrieb Jed Rothwell: > > Mattia Rizzi <mattia.ri...@gmail.com> wrote: > > How can rossi had a permit if inside the nuclear site there isn’t even >> a SINGLE “Nuclear Warning” panel? >> > > I don't know. I have not seen his application or permit. You have a good > point. It might be prudent to set up some signs. I am not sure where you > would put them, or how far away people should stay. Bianchini set up > detectors and found nothing, so they did pay some attention to this issue. > > Still, as far as anyone knows, cold fusion never generates dangerous > radiation. > > In contradiction to this, Rossi says the heat is made from soft gamma rays. > Some 100 kW of gamma rays are dangerous. > > > So it is a little silly to apply the safety standards of fission or > plasma fusion to it. This is like saying that hydrogen airships can explode, > so we should take extreme precautions when working with helium balloons. > > No it is like saying a helium Zeppelin is dangerous, because the > inventor says, it is filled with hydrogen ;-) > > - Jed > > >
