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Gamma radiation

  1. Mar 31, 2008 #1
    [SOLVED] Gamma radiation

    gamma radiation does anyone know how it is produced within the nucleus?
    and I know that gamma radiation takes place after a isotope has undergone a decay
    and is in an excited state. I know that what interest me is the very nature of the excited state! and how the gamma radiation is formed within the nucleus. I am mainly interested if anyone has tried to explain this or has prooved a theoretical model for how this takes place any information would be of interest since recently I have been working on my own theoretical model for this( with great pain and want to know what others have written)

    I am looking for books web sites anything that has a large amount of information on the subject of gamma radiation and its creation and very nature within the nucleus theoretical and otherwise. If it is an extremly complicated quantum mechanical explanation that is fine to anything is useful.
    Last edited: Mar 31, 2008
  2. jcsd
  3. Mar 31, 2008 #2
    QM explanation: If you model the nucleus as nucleons in a well, then pretty much any energy transition will emit a gamma ray, as long as it isn't forbidden (e.g., a dipole transition with angular momentum difference of 1).

    QFT explanation: As for how it is produced, the standard model pretty much covers it. Whenever you have an interaction of the form [tex]A_\mu J^\mu[/tex] where [tex]J^\mu[/tex] is some current operator, that will lead to an allowable source of photons. If you have high energies at your disposal (e.g., nuclear energies), those photons will be gamma rays.

    Sorry if this is too vague, but there is almost too much information on the subject. I'm not really sure if it is need of another model, though.
  4. Apr 1, 2008 #3
    Thank you for posting

    I found myself trying to solve a questio the other day and I checked online and apparently this has been mathematical problem for decades at that point I gave up and just accepted the intuitiveness of my answer ( which gauss already had prooved)
    ( the best possible method of packing spheres which represent nucleons within a spherical shape lol) proving that the best acheivable packing factor is .74 is a deuzy

    Ok so back the the guy who posted first thanks for posting thank you now
    I will search the information you have provide but directing to web site or free PFDs that I can downloand would be much appreciated .
  5. Apr 2, 2008 #4


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    See for example Introductory nuclear physics by Krane, and Nuclear many-body problem by ring, for a general introduction to nuclear physics. Also pick up nuclear models by greiner.

    I am always very sceptical to persons who would like to solve problems that have been solved ages ago and that they also lacks basic knowledge of the subject they are examine..

    I mean why is the best packing fraction of spheres relevant? you can't pack nucleon too dense due to fundamental properties of the nucleon-nucleon force.
  6. Apr 2, 2008 #5
    It is not just irrelevant. It is quite easy to find the radii of nucleon and nuclei on internet anywhere, assume they are spherical, calculate the packing ratio. Marcwhydothe, I don't know your theory and have always had great respect for Gauss, so why not doing the elementary calculation of the packing fraction in any nuclei right here ? Pick you prefered nucleus.
  7. Apr 2, 2008 #6
    your all correct

    On the other matter of my concern on the packing for sure your right that the electrical force and the resiual nuclear force will cause the sphere to be only of one size well its better to say will approach eachother with and exact distance.

    But now
    " wouldnt it make sense that nature would pack nucleons as close as possible so that the force of resistence the + charge which prevents the hadrons from absorbing each other ( this crude explanation but theres is no need to talk about gluons and pions or anything about elementry particles because the only thing that matter is the + electrical field within the nuclei that is distrubted and amplified by each proton and the residual nuclear force that binds them together

    Let me give you an example of what I mean

    Neutron--Strong force---Proton straight line

    neutron ---strongforce---Proton -SF untel the -EMF stops it---Pronton

    if the latter where to combine in lets say some how out of magic in a line straight line the volume it takes up would be greater then lets say if the arragenment was

    proton--neutron--proton ( right)
    but what about a triangle ( no that wouldnt really work because the pronton forces will push the nuclei farther appart.)

    get my drift why efficiency in packing is important?
    " idont really know if this makes sense but if you dont think it does Id love to hear you comments about the idea about how awful it is or if its an interesting idea and what discoveries deal with this
    alright thx evryone

    oh and nuclear physics - most books dont explain how gamma emition occurs
    (just cause you know that an electron absorb energy and goes to higher orbital then returns to ground state and emits a photon doest mean you udnerstand why it does this)

    gamma emission occurs when the nuclei is in an excited state usually occurs after an initial decay and is detected using gamma spectroscopy.( i know what happens not why it happens and if you know why then basicaly you have studie QM indepth beyond anything I know or even understand)

    Now Im only think about this stuff im not saying that any of this is true in fact i dont know but its just and idea that i really havent seen explain anywhere

    except for QFT - which I really dont know very well
    I know the basics of nuclear physic which answer what it does how to analyze it and other equations but doesnt seem to answer the why.
    Last edited: Apr 2, 2008
  8. Apr 2, 2008 #7


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    strange, in my books they explain why EM radiation is created..

    so you have studied QM, then have you studied nuclear physics with QM?

    Also follow the rules of this forum and dont discuss your own or crackpot 'theories'.
  9. Apr 2, 2008 #8
    The (EM) radius of nuclei A is approximately [tex]r_{0}A^{1/3}[/tex] with [tex]r_{0}\approx 1.2[/tex] fm. The (EM) radius of the nucleon is approximately 0.87 fm.

    The "packing fraction" is thus approximately independent of A : [tex]
    \left( \frac{r_{N}}{r_{0}} \right)^{3} \approx 0.38
    Last edited: Apr 2, 2008
  10. Apr 3, 2008 #9
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    Last edited: Apr 4, 2008
  11. Apr 3, 2008 #10
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    Last edited: Apr 4, 2008
  12. Apr 4, 2008 #11


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    So you are referring to crack-pottery web sites and mixing with wikipedia text and then says:

    "So initialy i was kinda agreeing with you guys but now theres no chance I my thoery wasnt as crack pot as you thought LOL"

    "I think my idea about packing does have merit and it seems i was right even though the first few sites i found where a little odd wiki showed i was on the right track maybe not perfect but id say pretty darn good
    Also these websites are just words and images, never physical formulas etc. If one just takes some basic quantum mechanics courses then start to examine the nucleus and its nucleons, then you'll see that things like packing nucleons like marbles are just rubbish.

    I mean, you have missinterprented the wikipedia totaly, when a nuclear physisics talks about a "spherical" nuclei, that has nothing to do with a real geometry shape. An analogy: Atoms are quantum systems also, and the electrons constitutes an "electron probability-cloud", the same holds for the nucleons in the nucleus. You cant talk about a real shape since shapes dont exists, just probablity distribution functions.

    That an Atom is said to be spherical has to do with that the probablity distribution function of have spherical symmetry (roughly speaking), I think you really need to study the basics.

    Can a moderator please lock this thread?
  13. Apr 4, 2008 #12
    your right about probability distrubution heisenbergs uncertainty principle one oh one
    i just thought maybe I could look at the nucleus differently this time but according to you my way is way off and thats good enough for me to stop this thread

    thx for your imput sorry if it pissed you off i think exploring new ideas and prooving them wrong is solidifys our understanding of physics oh well sorry
  14. Apr 4, 2008 #13
    Look, if you really were annoying we could just ignore your posts. Exploring new ideas is always interesting. The basic rule is just to stick to scientific method : basically you just need to display a test for your ideas. For instance, bring your ideas to the point where you do actually calculate a packing fraction. If it turns out to be 0.739999 or so, we will conclude that your model does not make a good job, if turns out to be 0.37 +/- 0.01 then we will be very impressed and explore the idea a little more, for instance by trying other predictions. You can also make predictions about gamma transitions, that is very interesting.
  15. Apr 4, 2008 #14


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    I was not anoyed, but I gave you two comments:

    i) Start from basic physics, that is accepted: what can we learn from that? How does the accepted model of atomic nuclei work and how is it related to actual data, and what is to be improved/changed? Those things you can learn from the books that I adressed in one my first posts. Also apply for university, take quantum classes and so forth. I encourage you.

    ii) Physics Forum rules are such that we don't discuss crack-pot theories here.

    Can you tell me what new insight in physics I gained from showing that your way to examine the atomic nuclei is not good?

    I encourage you to study real physics and how it works and remain curious. The more your know, then more you can do, and you wont spend so much time on meaningless crack-pottery.

    I remember there was a guy here a couple of months ago and was talking about his solid lattice atomic nuclei model, and he listed 4 or 5 "facts" that we know of in nuclear structure physics which still are problems, and that his model could solve them.

    The funny thing was that I could within a couple of minuts proove to him that his first "facts" where either totaly wrong and misinterpret. Or that 'modern' (1950's) nuclear structure physics has solved the "facts" that was not wrong. Without any book beside me. Too bad he had spend so much time on it, and even written a book about it.. it is just sad. So again, I encourage you to spend your valueble time on studying real physics.
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