Talk:Gamma ray

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[edit] A question on gamma decay

When the daughter nucleus is in an excited state we mean that one of its electrons is on a higher floor, right? The nuclues itself (protons, neutrons, quarks) can't be in an excited stage, right? So for example men cobalt 27 60 becomes nickel 28 60 it gets a new set of electron floors (energy levels) and therfore a few electrons may be on a to high floor given the new more strongly positively charged nuclues, so they jump down and throw out a photon?--JR, 11:57, 24 May 2007 (UTC)

Yes, nucleons (protons, neutrons) can be in an excited state. The photons emitted by electron transitions are by definition not gamma rays. All nuclear radiation is by definition due to transitions in the state of the nucleus, not the electrons. Rwflammang 14:43, 29 August 2007 (UTC) gamma rays come from your dick going in and out of a hole in a dog. —Preceding unsigned comment added by 209.189.130.63 (talk) 16:02, 5 May 2008 (UTC)

[edit] I gave these comments a headline

"Gamma rays are almost produced alongside alpha and beta" Do you mean "always produced"?

While X-rays are generated by electronic transitions. Gamma-rays are usually more energetic than X-rays, but this is not always the case. For example the 14.4 keV gamma-ray from Co-57 -> Fe-57, is less energetic than many X-rays.

Also, gamma rays can be formed by matter/antimatter interactions, such as electron-positron annihilation.

"Gamma rays from nuclear fallout would probably cause the largest number of casualties in the event of the use of nuclear weapons in a nuclear war"

Irrespective of the case that the large explosion, fireball and heat wave would cause the largest number of immediate casualties, with climate change causing most post-war problems, this is still incorrect: The penetrating power, and small cross section, that makes gamma radiation difficult to shield also means that they are very unlikely to interact with your body. The real danger is vast amounts of alpha and beta emitting dust getting lodged in and around your body and in the foodchain.

[edit] Gamma Rays

I think this page could be moved to "Gamma Rays", the term most often used to refer to this portion of the EM spectrum. Thoughts? I would go with gamma radiation. It's not about rays, neither ray or rays is really a good name. Current name matches X-ray, though.

[edit] Hulk

I don't think that bombarding oneself with gamma radiation is going to create a Hulk. Stan Lee himself said that he didn't even know what a gamma ray was; he just chose it because "gamma ray" sounded scientific. 4.158.60.136 04:37, 1 December 2005 (UTC)


You do realise that the HULK would have about a billion different types of tumours just because of being bombarded by that amount of gamma radiation.

And that's why I deleted the implication that it could. "Such transformations are extremely rare". Bah! -SuperGerbil

Nonsense! Everybody knows that gamma rays can give you superhuman powers. Javguerre 12:55, 27 June 2007 (UTC)

[edit] How are gamma rays detected/observed?

See title, Pcb21 Pete 08:52, 26 April 2006 (UTC)

[edit] Using Cockroach exoskeleton insted of lead to shield against gamma rays

I've just read that the cockroach exoskeletion helps shield them against alpha, beta, and gamma rays. Could a possible application be - that we can shield people from radiation by using the cockroach exoskeletion instead of lead?

Where did you read that? Cockroach states that their radiation resistance is from the fact that their cells divide less often than humans'. --Ihope127 20:38, 6 June 2006 (UTC)


This is true, I don't know it in greater depth by after nucleur explosions and radiation cockroaches actually still live.

[edit] References

Right now, it is not clear what do references in the end of the article refer to. Why not to migrate to the <ref> system? —Matveims 01:48, 29 May 2006 (UTC)

[edit] industrial uses

Gamma rays also have an industrial application. They are used the same way x-Rays are used to produce images. Weld and other such sensitive items are inspected by bombarding it with gamma rays to create an image of the interior of the item on a piece of film. The most common Isotopes used are: Iridium 192, Cobalt 60, and Cesium 137.

-Devin Snyder

source: http://www.ndt-ed.org/EducationResources/CommunityCollege/Radiography/cc_rad_index.htm —The preceding unsigned comment was added by Myghell (talk • contribs) 07:15, 7 March 2007 (UTC).


Gamma rays are also used to in quarantine treatment as an alternative to heat treatment should it be impracticle ( especially on foodstuffs) .-- Librarianofages 04:29, 27 March 2007 (UTC)

[edit] Health effect

"The gamma rays are the most dangerous form of radiation emitted by a nuclear explosion because of the difficulty in stopping them. Gamma-rays are not stopped by the skin." This is not quite true - the most dangerous type of radioactive exposure occurs when radioactive gas or dust which is undergoing alpha decay enters the body. The fact that "gamma rays are not stopped by the skin" is actually a good thing in some ways, as gamma rays are far more likely to pass straight through the body without being absorbed than alpha or beta radiation is. Gamma rays are also far less ionising than alpha or beta radiation. Possibly this section needs to be rewritten? Sbiki 14:46, 20 April 2007 (UTC)

[edit] Small copyright infringement

If anyone has a vested interest in this article and wants to follow this up. It's only small, but text has been copied from this article, verbatim, with no attempt to attribute it. Full details here: http://en.wikipedia.org/wiki/Wikipedia:Mirrors_and_forks/Def#Fallen_Earth_Forums

  • Done. 87.194.203.205 05:44, 5 October 2007 (UTC)

[edit] Question on Final Sentence

As a recommendation referring to one of the final sentences. In my interpretation more likely than not implies a percentage slightly greater than 50% however in this context a change might be necessary such that the sentence reads: "by an overwhelmingly large margin..." Haven't edited as a consensus on this is necessary.

[edit] Whole missing section!

could someone please add a secton on the eenage mutant nija turtles

Veggieburgerfish 19:42, 17 September 2007 (UTC)

after all they are heroes in a half-shell

Actually, a section dedicated to popular references to Gamma Rays wouldn't be that bad. --Antonio.sierra 22:08, 14 October 2007 (UTC)

[edit] Misinterpretation of study

Prior to my edit, the article provided a statistic for comparison, stating that the risk of cancer (other than leukemia) was elevated by 32% for atom bomb survivors. The link that it quoted, however, stated that it was 0.32 (ie, 32%) per Sievert of exposure. Without knowing the average exposure of the atom bomb survivors, this isn't really very useful for comparison, so I've removed it.

Ideally, it should be reinserted with a corrected statistic, based on the radiation dosage received by atom bomb survivors. Unfortunately, the linked article doesn't provide a reference for the statistic, so I can't find the original study to look it up. —Preceding unsigned comment added by 130.155.198.32 (talk) 04:41, 21 December 2007 (UTC)

[edit] Needs a history section.

I was trying to find out who discovered gamma rays and when...but no history section? SteveBaker (talk) 18:12, 10 February 2008 (UTC)

Discovered and investigated by French physicist, Paul Villard, around 1900. He established some of its properties, correctly noting its similarity to X-rays. Rutherford was probably the first to actually call them gamma rays, and to understand that they were high-energy photons. Read some more here. I will add a paragraph when I get some free time. Cragwolf (talk) 02:15, 11 February 2008 (UTC)

[edit] Wavelength?

So, in what range of wavelengths on the electromagnetic spectrum do gamma rays fall? --66.51.190.36 (talk) 00:31, 20 February 2008 (UTC)

Less than 10 picometres. Thunderbird2 (talk) 19:16, 20 February 2008 (UTC)
Usually, but the distinction from other kinds of EM radiation is often made depending on the source (gamma rays are produced in an atomic nucleus). The 229Th nucleus has an excited state at a few eV, and its "gamma radiation" has a wavelength of more than 100 nanometers. Icek (talk) 04:02, 10 March 2008 (UTC)
So what is the criterion then? Is it that all EM radiation from an atomic nucleus is considered to be "gamma rays"? Or does it depend on the nature of the transition? Thunderbird2 (talk) 07:09, 10 March 2008 (UTC)
Unfortunately there seem to be different conventions. In physics it is generally the source, and there are possibly even "optical gamma rays". In astronomy it's the wavelength, as this is what determines your method of measurement (and you don't prepare the emitter so you don't know as well as in physics where the radiation was produced). Icek (talk) 21:15, 11 March 2008 (UTC)
Thanks, that helps. By an "optical" gamma ray, do you mean one produced by a sub-atomic interaction that happens to have a visible wavelength? Thunderbird2 (talk) 21:35, 11 March 2008 (UTC)
Yes. Icek (talk) 04:06, 12 March 2008 (UTC)
I disagree with Icek. I'm a physicist, and have done work in gamma-ray spectroscopy. Physicists refer to anything with an energy of >~100 keV as a gamma ray. It's a vague, fuzzy boundary, but the fuzziness extends less than a factor of 2 on either side of 100 keV. If a nucleus emits something with an energy of 10 keV, then people in my field definitely refer to that as an x-ray, not a gamma ray, regardless of the source. The seat-of-the-pants distinction is that x-rays are not very penetrating, and interact mostly via the photoelectric effect, whereas gammas are very penetrating, and interact mostly via Compton scattering (or pair production, at high energies).--76.93.42.50 (talk) 01:33, 18 March 2008 (UTC)
Can either of you quote a source? Could it be that different conventions are used in different fields? Thunderbird2 (talk) 07:08, 18 March 2008 (UTC)
I think I erred when I said that the different definitions are used in physics and astronomy respectively, but there are certainly physicists who call low energy nuclear radiation "gamma": Utter et al. (1999), Reexamination of the Optical Gamma Ray Decay in 229Th, Physical Review Letters 82(3).
Icek (talk) 12:39, 18 March 2008 (UTC)

[edit] Coil wavelength

This is a legitimate, if somewhat obscure (to this user) term. It keeps turning up here linked to the article dealing with the physical manifestations of a coil. Can any user either add a paragraph here covering the term, or even start a new article? --Old Moonraker (talk) 06:16, 20 May 2008 (UTC)