What produces Gamma rays?

Answer 1

Gamma rays are typically produced by the decay from high energy states of atomic nuclei, called gamma decay, but they are also created by other processes. For instance, gamma rays are also produced by secondary radiation from atmospheric interactions with cosmic ray particles. Also, rare terrestrial natural sources produce gamma rays that are not of a nuclear origin, like lightning strikes and terrestrial gamma-ray flashes. Plus, they are produced by astronomical processes where very high-energy electrons are produced that cause secondary gamma rays via bremsstrahlung, inverse Compton scattering and synchrotron radiation.

Answer 2

Supernovae and active black holes are by far the most interesting gamma ray emitters. Active black holes can actually focus them into rays of death, and supernovae which form black holes can briefly shine brightly enough that we can see them here even if the entire combined light from every other object in that galaxy is too dim for us to see. They're also emitted by some types of nuclear decay, but you're not likely to come into contact with them. The fact that a single one can cause significant damage to a cell leads us to try to avoid them. Uranium decay is a pretty good source of them.

Answer 3

most radioactive materials

alpha radiation = high-energy alpha particle leaves core

beta radiation = neutron turns into proton, shooting high-energy elektron out of the atom

gamma radiation = energy released from alpha and beta(and K-capture, elektron from K-shell gets caught in core, reacting with a proton to form a neutron) radiation by mass-reduction caused by nuclear decay

Answer 4

Gamma rays are emitted by a couple of means:

1) They are emitted from the atomic nucleus as a means of removing excess energy from an excited nucleus. Often emitted simultaneously (or immediately after) alpha/beta (eg I-131, beta+gamma), but can be several hours later in the case of isomeric transition (eg Tc-99m, IT).

2) Annihilation radiation is (as far as I know) categorised as gamma radiation. This is most commonly observed after positron emission (beta+ decay). A positron is antimatter and will inevitably annihilate with an electron when travelling slowly and in close proximity. This results in two identical gamma rays emitted each has energy equivalent to the rest-mass energy of an electron (or positron; they're the same). A great practical use of this is in PET scanning.

Answer 5

gamma radiation, is caused by particles that can go through aluminium but leed, or a few centimetres of concrete.

Answer 6

Gamma rays originate from the decay of radioactive substances