What is Gamma: Definition and 711 Discussions

Gamma (uppercase Γ, lowercase γ; Greek: γάμμα gámma) is the third letter of the Greek alphabet. In the system of Greek numerals it has a value of 3. In Ancient Greek, the letter gamma represented a voiced velar stop /ɡ/. In Modern Greek, this letter represents either a voiced velar fricative or a voiced palatal fricative.
In the International Phonetic Alphabet and other modern Latin-alphabet based phonetic notations, it represents the voiced velar fricative.

View More On Wikipedia.org
Recent contents Top users
  1. P

    I Gamma ray cross sections from classical plane wave

    I am aware that in classical electrodynamics a metal exponentially attenuates TEM waves. I am wondering if this fact is sufficient to obtain estimates of the cross section of low energy gamma rays in metals. Obviously it would fail for higher energy gamma rays where Compton scattering and pair...
  2. R

    Energy of the photon emitted in a gamma ray decay

    Homework Statement An Fe nucleus (A=57) decays from an excited stated to the ground state by emitting a gamma ray. The energy of the photon is 14.4 KeV when the nucleus is held fixed. If the nucleus is free to recoil then the energy of the photon emitted will be? Homework Equations ## E =...
  3. T

    Proof of trace theorems for gamma matrices

    Hi, I'm currently going through Griffith's Particle Physics gamma matrices proofs. There's one that puzzles me, it's very simple but I'm obviously missing something (I'm fairly new to tensor algebra). 1. Homework Statement Prove that ##\text{Tr}(\gamma^\mu \gamma^\nu) = 4g^{\mu\nu}##...
  4. Mr Davis 97

    Integral using the gamma function

    Homework Statement I am trying to evaluate the following integral: ##\displaystyle \int^{\infty}_0 (1 - e^{-x}) x^{-\frac{3}{2}} \, dx## Homework EquationsThe Attempt at a Solution When I split the above integral, I get the following ##\int^{\infty}_0 x^{-\frac{3}{2}} \, dx - \Gamma...
  5. P

    According to Maxwell, a gamma ray can be as energetic as a radio wave (given equal E amplitudes)?

    According to the old thery of light the energy carried by by a wave is proportional to the amplitude of the electric field not to the frequency as Planck proposed, so an eletromagnetic radiation in the gamma spectrum carry the same energy as a radio one if their amplitude is the same? They only...
  6. Daniel Petka

    Exploring Gamma Photon Ionization: Effects on Wavelength and Ion Creation

    Gamma rays scatter and ionize atoms, which stretches out their wavelength, right? How many ions could a single gamma ray photon create before it's absorbed due to the photoelectric effect?
  7. U

    I Is There a Reliable Link Between Gamma Radiation and Childhood Leukemia?

    I'm trying to find out how much gamma-radiation the average human is exposed too from background radiation. But all I can find are numbers describing the total background radiation, not just the gamma radiation alone. Does anyone know where I can find this information?
  8. ShayanJ

    A Integral in terms of Gamma functions

    Does anyone know how I can prove the following equation? ##\displaystyle \frac 1 {d-1}-\int_0^1 \frac{dy}{y^d} \left( \frac 1 {\sqrt{1-y^{2d}} }-1\right)=-\frac{\sqrt \pi \ \Gamma(\frac{1-d}{2d})}{2d \ \Gamma(\frac 1 {2d})} ## Thanks
  9. Frank Li

    I Can anyone explain the Gamma function to me?

    Γ(n) = ∫x→∞ tn-1 e-t dt?
  10. M

    B Is the Gamma Ray Burst Diameter Wide Enough to Engulf Our Solar System?

    Is it true gamma ray burst diameter can be as big as the solar system and the sky would become bright with its light even if it is 4000 light years away? Saw this at History Channel.
  11. B

    A How Do Gamma Matrix Identities Relate to the Charge Conjugation Operator?

    Consider the matrix ##C = \gamma^{0}\gamma^{2}##. It is easy to prove the relations $$C^{2}=1$$ $$C\gamma^{\mu}C = -(\gamma^{\mu})^{T}$$ in the chiral basis of the gamma matrices.1. Do the two identities hold in any arbitrary basis of the gamma matrices? 2. How is ##C## related to the charge...
  12. Old Chinaman

    B Understanding the EPR Paradox - Exploring the Gamma Factor

    I am not a physicist but interested in the decade long debate between Einstein and Niels Bohr, especially in the philosophical implication of the EPR Effect. I've been wondering if anyone could explain why Einstein, Podolsky and Rosen didn't applied the Lorentz Transformation formula - the...
  13. Safinaz

    I ## \mu~\to e~ \gamma ## decay width and neutrino propagator

    Hi all, I'm studying ## \mu \to e~ \gamma ## decay from cheng & Lie' book " gauge theory of elementary particles ". In Equation (13.84), he wrote the neutrino propagator ## \sum_i \Big ( \frac{U^{*}_{ei} U_{\mu i}}{(p+k)^2-m_i^2} \Big), ## (where the sum taken over neutrinos flavors) in the...
  14. G

    I Deriving Magnetic Force w/ Approximated Gamma-Factor at UVA

    Hi. On the webpage of a lecture at the University of Virginia, I found this derivation of the magnetic force using Lorentz contraction and electrostatic force. They approximate the gamma factor to the order of ##v^2## and get the correct result. How is it possible to get to the same result...
  15. binbagsss

    Show two inequalities - (context gamma function converges)

    Homework Statement I'm not after another proof. I've just got a couple of inequalities I don't know how to show when following a given proof in my book. These are: Q1) ## 0\leq x \leq 1 \implies x^{t-1} e^{-x} \leq x^{t-1} ## So this is obvioulsy true, however I think I'm being dumb because...
  16. Clara Chung

    How does a gamma ray get converted to visible light

    In the process of heat transfer from core to photosphere, each gamma ray in the Sun's core is converted during scattering into several million visible light photons before escaping into space.----from Wikipedia How does heat transfer related to scattering? Is it related to Raman scattering as...
  17. S

    A What is the true definition of the covariant gamma matrix ##\gamma_{5}##?

    Covariant gamma matrices are defined by $$\gamma_{\mu}=\eta_{\mu\nu}\gamma^{\nu}=\{\gamma^{0},-\gamma^{1},-\gamma^{2},-\gamma^{3}\}.$$ -----------------------------------------------------------------------------------------------------------------------------------------------------------...
  18. S

    A Hermitian properties of the gamma matrices

    The gamma matrices ##\gamma^{\mu}## are defined by $$\{\gamma^{\mu},\gamma^{\nu}\}=2g^{\mu\nu}.$$ --- There exist representations of the gamma matrices such as the Dirac basis and the Weyl basis. --- Is it possible to prove the relation...
  19. Clara Chung

    B What is the recommended method to reduce gamma ray exposure?

    A gamma ray source emits gamma ray to a photographic plate in a container. The book said the blacked region on the photographic plate wouldn't be affected if the gas pressure of the container was increased. However, I think that the gamma ray will ionise more air molecules and lose more energy...
  20. M

    MCNP Gamma Decay: Neutron & Photon Calculation in Reactor Cores

    Hi , This is my first post in this forum, I am new and happy to be in this forum :) My question is, during the calculation of neutron and photon of a single-point reactor core, does MCNP5 taking into account the gamma decay? because during fission process, fission product can emit gamma. Does...
  21. Sebastiaan

    Using Gamma Ray reflector to reduce mass of Shadow shield

    Let's say we have manned space vessel powered by a highly power but radioactive rocket engine, producing a lot of deadly gamma rays. The classical answer to this problem is to use a shadow shield. However, Nuclear Shadow Shields are very heavy. What about the idea of instead of trying to absort...
  22. C

    Why don't we have gamma ray microscopes?

    Homework Statement Why? We can use shorter wavelengths than that of electrons to view electrons and more? What is stopping us? Can the image not be imprinted on a plate of some sort instead of being viewed by the eye directly? Homework Equations none The Attempt at a Solution I'm guessing no...
  23. CapnGranite

    Effects of a gamma ray burst on earth

    http://phys.org/news/2016-10-deadly-nearby-gamma-ray.html How deadly would a nearby gamma ray burst be? The original paper in Astrobiology is locked, but this summary is pretty complete. "A burst at the South Pole fits in with theories of the Ordovician extinction because the measured...
  24. N

    B Question About Gamma Factor: Exploring Limits

    I don't know why this problem just occurred to me- sorry if it's a silly question: Why is it that there isn't a limit to how high the gamma factor can be? How can you ever have a gamma factor which is more than 2, for example? Although if you plug the numbers into the equation for gamma it makes...
  25. N

    Stargazing H.E.S.S. gamma ray telescope got an image of the moon

    https://en.m.wikipedia.org/wiki/File:Moon_egret.jpg Can we use better telescopes of this type (ground based gamma rays telescopes) to image the surface and subsurface of a planet with a lot of resolution?
  26. J

    I How to derive full solar sprectrum from gamma rays

    I understand that the fusion of hydrogen to helium in our sun's core generates gamma rays. My question is how are these gamma rays transformed to the full spectrum of photons that we that we observe from earth?
  27. DarkBabylon

    B High energy protons and electrons to gamma radiation

    Can high energy incoming protons and electrons be absorbed and their energies remitted by photons? If so what are the typical ranges of energies emitted and are they heading in the same direction as the original emission if we had a sheet of metal being bombarded by those protons and electrons?
  28. Hercuflea

    Fluence rate of gamma source - getting two different answers

    Homework Statement A 1 meter long uniform line source of high energy photons emits 10^7 photons /sec. Calculate the particle fluence rate (flux density) at a point P 1m away from the midpoint of the source. Homework Equations ## dN = number~of~particles ## ## da = differential~area## ##\Phi =...
  29. M

    Products of gamma matrices in n dimensions

    Hello, i have here some identities for gamma matrices in n dimensions to prove and don't know how to do this. My problem is that I am not very familiar with the ⊗ in the equations. I think it should be the Kronecker-product. If someone could give me a explanation of how to work with this stuff...
  30. EBPoncho

    PET/CT Gamma Ray Protection with Lead Apron

    I was informed I might get a better response by posting to this forum, so sorry for the double post. Hello all, I am currently attending a service course for a PET/CT system for my employer. We have been covering the physics behind the function of detectors and my instructor said something...
  31. T

    Standing wave in a column of methane, find gamma of methane

    Homework Statement A standing wave with a frequency of 1100 Hz in a column of methane at produces nodes that are 0.200 m apart. What is the value of γ for methane? (The molar mass of methane is 16.0 g/mol)Homework Equations v = sqrt ( γRT/M) where R is 8.341, T = 20 °C and M = 16.0 g/mol. v=fλ...
  32. A

    Electrons producing gamma photons in accelerators

    When electrons produce photons in accelerators what is the mechanism called? and who was the first to do it?
  33. Dade Murphy

    Gamma spectroscopy over time?

    Hello! These might be silly questions to the experienced, but this will be my first time trying gamma spectroscopy, so I'm a newbie. Firstly, I'm wondering if there's some software that will record changes in the spectrum over time? I know some people have been doing audio recording, but it...
  34. ali khotbesara

    NaI detector in water source -- gamma & beta

    Homework Statement simulation of bersiv function of NaI detector it's in cylinder of water with volumetric source of Potassium40 (90% beta 1.31 mev & 10% gamma 1.504 mev ) how candefin define electron and gamma Volumetric source in mcnpx (6) ...
  35. S

    Determining Gamma Ray energy from spectrum

    Homework Statement (Preface: I am not a physicist) The pulse height spectrum of a radioactive source known to emit high energy photons was measured using a small detector. Three distinct peaks were observed at heights of 7.38, 6.49 and 5.60 V, along with a continuous portion of the spectrum...
  36. A

    Determine half life from gamma radiation

    I'm working on a lab and the task is to determine the half life of an element studying the beta radiation or the gamma radiation (emitted from the daughter). I have all the data and I'm done with the beta part, that was pretty straight forward. I have no clue how to relate the gamma radiation to...
  37. L

    A Exploring Gamma Functions: Analytic Possibilities & Integrals

    I have two questions related Gamma functions 1. Finding ##\Gamma## analytically. Is that possible only for integers and halfintegers? Or is it possible mayble for some other numbers? For example is it possible to find analytically ##\Gamma(\frac{3}{4})##? 2. Integral...
  38. Parsifal1

    Does gamma equal density in Kg/m^3?

    I want to use the equation: Fr='gamma'*distance from centroid*Area but the example is showing density in N/m^3 while I only have the density in kg/m^3 Does this mean I have to multiply it by 9.81 to get the right answer? Thanks.
  39. R

    I Gamma Function Explained for Upperclassmen Math Students

    I took differential equation over the last year and we talked about gamma functions in class but it wasn't in our books and I don't speak broken Russian so it was hard to understand what was going on. I'm wondering if the gamma function is similar to the dirac or heaviside functions and if...
  40. Toreno

    I Is nuclear fusion induced by gamma photons possible?

    Hi folks, IMO, it should be possible to initiate a nuclear fusion of H1-H2 and H2-H2 in crystals of Lithium Hydride induced by gamma photons emitted form decay of Na24. Could anyone please verify if the following is correct? By using nuclear photodisintegration effect, we need a gamma photon...
  41. O

    I How long can you be exposed to gamma radiation for

    So my question is, how long can you be exposed to a gamma radiation for? Specifically, I've been working with a sealed cobalt-60 source for a final presentation. Now my professor noted to me that these sources we're using aren't radioactive enough to cause us any harm. However, I've been...
  42. Developer_CM

    Gamma Ray Spectroscopy - 97 keV Peak for U238 Metal

    I recently acquired a 39 gram sample of U-238 metal. I ran a gamma spectrum on the sample and found a major peak around 97 keV. I couldn't find any documents that mentioned this peak for U-238, but it is very prominent. I ran a gamma ray spectrum on a 5 gram Uranium Oxide sample and it also...
  43. M

    Dirac Trace Algebra: Which Gamma Matrices Matter?

    Homework Statement This isn't a homework problem; it's just something I'm working on and I'm a little confused as to how to go about dealing with what I have. I have several traces of Dirac's gamma matrices, and I know that the trace of an odd number of gamma matrices is zero. So my first...
  44. ChrisVer

    Python Problem with a gamma function/error message

    I wrote the following python script in order to try and look how $$\sum_{i=1}^\infty f(n) = \sum_{i=1}^\infty \frac{\Gamma(n+1/2)}{n^2 \Gamma(n)}$$ behaves. However it appears to have some problem with my function f(n) for n=172 and above throwing this error: I thought that there was a problem...
  45. Cyril St-Amand

    Dismantlement of Nuclear Power Plant (Canada)

    Hi everyone this is my first time posting here, First of all, excuse my english because here in Mtl we speak French mostly. My team and I are working on an university project in Montreal (Qc) Canada (Polytechnique) regarding the recycling of radioactive material waste. We are working on the...
  46. Jonathan Scott

    A Could gamma rays imply GW sources not black holes?

    When I saw the report of a gamma ray burst associated with the LIGO GW event, my immediate thought was that the obvious explanation is that the compact massive objects were not in fact black holes, and the gamma ray burst was from the energy of the final collision and merger. This would...
  47. UseAsDirected

    Nitrogen transmutation to carbon-14 (radiocarbon) via gamma

    Hello, I am trying to fully grasp the transmutation of nitrogen into radiocarbon (radiocarbon or carbon-14) via gamma collision high in the atmosphere But, I don't because I cannot whether something also happens to the electron. The canonical description is thus. High energy gamma particles...
  48. Jonathan Scott

    A Gamma ray burst associated with LIGO GW event

    Quite unexpectedly, it seems that the Fermi Gamma-ray Burst Monitor spotted what appears to be a hard gamma-ray burst about 0.4s after the LIGO GW event, lasting about 1s: http://arxiv.org/abs/1602.03920 This is not expected from a black hole merger (and as a black hole sceptic, I find it very...
  49. N

    Can multicellular life be sustained with gamma rays?

    If there are bacteria that can get their energy from gamma rays (thus thriving on nuclear reactors), can multicellular life do it too? If so, wouldn't that broaden the parts of the universe where life could arise?
  50. FallenApple

    Bounding a truncated normal with a gamma

    So say I have a truncated normal. That is, N(mu,sigma) that is from 0 to infinity only. I need to find a Gamma such that a constant C*Gamma(A,B) is always above N(mu, sigma). How would I go about finding such a A, B that would work given fixed mu and sigma?
Back
Top