Gamma Definition and 714 Threads

Hey everyone, I need to be able to be able to explain how a gamma spectrometer (NaI scintillator) can determine the energy of a given gamma ray (or more particularly, determines the effective dose rate, but that shouldn't be to hard once I figure out how to get the energy). The problem, as far...

From what i have read the gamma ray frequency cap ranges from 3×10^19 to 3×10^24. I want to know what you guys have heard it is. Are the highest measured gamma ray from a supernova calculated with any time dialated effects? Also what is the thoertical cap of something higher than a gamma ray...

Hi there! The experiment: I'm counting Gamma and beta rays emitted from gamma and beta cylindrical sources, for counting I'm using a simple GM counter, which has nearly the same cylindrical shape (i mean diameter). As we all know this are electromagnetic emissions, so they distance must...

hi my friends I want some informations to study about gamma wave and interactions of it on humans cells.thancks alot.

On the included link, it is calculated that 5% of payouts are around $627 and 95% of payouts are at $1444. I would appreciate if someone can direct me as to how the came up with this answer. http://www.brighton-webs.co.uk/distributions/gamma.asp"

Homework Statement Hi Guys, I have been given the following The random variable X has a gamma (\alpha,\beta) distribution; ie X has pdf f_{X}(x)=\frac{x^{\alpha-1}e^{\frac{-x }{\beta}}} {\Gamma (\alpha)\beta^{\alpha}}\text{for }x \geq 0 (a) Determine the pdf of...

\Gamma(n) = (n-1)! Corrrect?

I need to know the practical applications of the absorption of gamma rays in materials.

I'm very confused By performing a lorentz transformation on a spinor \psi\rightarrow S(\Lambda)\psi(\Lambda x) and imposing covariance on the Dirac equation i\gamma^{\mu}\partial_{\mu}\psi=0 we deduce that the gamma matrices transform as S(\Lambda)\gamma^{\mu}...

Hello, When writting a gamma distributed RV we need to know the shape and scale parameters. How to find the value of these parameters? Thanks in advance

Is there any on-line reference which describes the interaction of high energy (> 100 Mev) gamma rays with matter. These are gamma rays from gamma ray bursts, etc. in contrast to low energy from nuclear radiation.

Homework Statement I read in a paper that: \Gamma\left(c,\,d\frac{x+e}{x-y}\right) = (c-1)!\,exp\left[-d\frac{y+e}{x-y}\right]\,exp[-d]\,\sum_{k=0}^{c-1}\,\sum_{l=0}^k \frac{d^k}{k!}{k\choose l}\left(\frac{y+e}{x-y}\right)^l Homework Equations But the incomplete gamma function...

Could you consider the gamma function to be a closed form representation? If I could express a numerical series in terms of the gamma function, would it be considered a closed form representation?

Hello, I'm attempting to analyse the data recovered from an experiment that I performed in lab, but I'm having some problems understanding how to properly apply the statistical methods learned to this specific problem. Essentially, the experiment consisted of placing a source of gamma rays...

http://news.yahoo.com/s/afp/20090219/sc_afp/sciencespaceastronomy This was one was supposed to be 12 billion LY away. How do we tell? If it is using red shift, how do we know what it looks like unshifted?

gamma matrix trace Paradox?? Hello, i tried to evaluate this particular little guy: \text{Tr} (\gamma ^0 p_\mu \gamma ^\mu \gamma ^0 q_\nu \gamma ^\nu ) using these identities: \gamma^0 \gamma^0 = I \text{Tr} (\gamma^\mu \gamma^\nu \gamma^\rho \gamma^\sigma) = 4 (g^{\rho \sigma} g^{\mu \nu}...

I remember reading before that hydrogen gas is "transparent" to gamma rays. What does this mean? I know it has something to do with the gamma rays not heating the hydrogen. Also, would Xenon gas be transparent to gamma rays?

Homework Statement For the case of a strong shock propagating into a gas with \gamma=7/5 What is the ratio \rho2/\rho1 Homework Equations \rho\ u=constant P+ \rho\ u^2=constant \frac{1}{2} u+ \frac{\gamma }{\gamma -1}\frac{\ P}{\rho} = constant The Attempt at a Solution I can use the 3...

How to prove that this formula is correct: \lim_{x\to\infty} \frac{\Gamma(x+1)}{\sqrt{2\pi x}\big(\frac{x}{e}\big)^x} = 1 I have seen a proof for this: \lim_{n\to\infty} \frac{n!}{\sqrt{2\pi n}\big(\frac{n}{e}\big)^n} = 1 but it cannot be generalized easily for gamma function. The proof...

\Gamma(z) = \int\limits_0^{\infty} t^{z-1} e^{-t} dt I can see that if \textrm{Re}(z)>0, then the integral converges, and that if \textrm{Re}(z)\leq 0 and \textrm{Im}(z)=0, then it diverges. However, I found the case \textrm{Re}(z)\leq 0 and \textrm{Im}(z)\neq 0 more difficult. t^{z-1} =...

can anybody help me to proove gamma(n+1/2)=(2n)!*sqrt(pi)/((4^n)*n!) thank you

I know that theorically the numbers of counts between compton edge and the photopeak must be zero. In practice it doens't occur. Why? Thanks in advance!

1. Numerically approximate \Gamma(\frac{3}{2}). Is it reasonable to define these as (\frac{1}{2})!? 2. Show in the sense of question 1. that (\frac{1}{2})! = \frac{1}{2}\sqrt{\pi} at least numerically. How am i supposed to attempt this numerically? given that i do not know additional...

Why does Mathematica sometimes give Gamma, the funtion and sometimes !, the factorial? What is the differences?

Okay, I'm writing a short response of about one page right now. Here's the question: Regarding soft gamma ray repeaters, 1. Is there any connection between the electromagnetic radiation and gravitational radiation? (specify: luminosity of the source? Thresholds?) and 2. How much...

Homework Statement For what value of v does Gamma (G) =1.0100? Observe that for speeds lower than this value, time dilationand length contraction are effects amounting to less that 1% Homework Equations L=Lp/G=Lp(1-(v^2/c^2))^2 The Attempt at a Solution I do not know where to...

I was reading this: https://www.physicsforums.com/showthread.php?t=181830 I was wondering if there is any up to day info about the speed of gamma ray burst that could confirm or debunk these claims. Or are LQG and String Theory in troubles?

Homework Statement \int e^{-\frac{2Zr}{a}}*r^{-1}dr Boundaries:[0,R] Homework Equations --- The Attempt at a Solution I tried to solve this with lower incomplete gamma function and got \gamma(0,\frac{2ZR}{a}) which is infinite i think. Z=81,a:Bohr radius,R=r0*A^(1/3)...

http://arxiv.org/abs/0810.2481 Gamma-Ray Burst at the extreme: "the naked-eye burst" GRB 080319B P.R. Wozniak, W.T. Vestrand, A.D. Panaitescu, J.A. Wren, H.R. Davis, R.R. White (Los Alamos National Laboratory) accepted for publication in Astrophysical Journal (Submitted on 14 Oct 2008) "On 19...

what's the difference between gamma rays and x rays?

http://www.sciencedaily.com/releases/2008/09/080919185809.htm * "This is the most amazing burst Swift has seen," said the mission's lead scientist Neil Gehrels at NASA's Goddard Space Flight Center in Greenbelt, Md. "It's coming to us from near the edge of the visible universe."...

Homework Statement Show that the integrand of \Gamma(s+1)=\int_{0}^{\infty} t^se^{-t}dt may be written as e^{f(t)} where f(t)=s\ln{t}-t. Show that f(t) is maximum at t=t_0 and find t_0. If the integrand is sharply peaked, expand the integrand about this point (ie Taylor expansion) and...

guys can u please help me out in calculating the posterior distib of the gamma function of form : p(lambda/alpha,beta) = (beta^alpha)*lambda^(alpha-1)*(e^(-beta*lamda)))/gamma(a) lambda>0 mean=alpha/beta mode = (alpha-1)/beta ;alpha>0 the integration seems really tuff which makes...

Very cool image. Does anyone know, is anything in the information we got from this so far at all surprising? Is it likely we will learn anything about gamma ray bursts from this or is more information

I Heard That the gamma function explains the strong nuclear force . \Gamma \left( z \right) = \int\limits_0^\infty {t^{z - 1} } e^{ - t} dt How does it explain the Force? Thanks

In gamma-ray spectrometry with germanium detector, the summing effects have to be taken into account at low source detector distance. The peaks due to coincidence summing of X+X, X+gamma, gamma+gamma rays can complicate the spectrum obtained by this type of detector and significantly change the...

\gamma = csc(cos^{-1}(v/c)) \gamma^{-1} = sin(cos^{-1}(v/c)) Is there something wrong with this derivation? If not, why isn't this the more formal way of writing it, it seems a lot more simple?

Hello everybody, actually yesterday i read about an experiment "ATTENUATION OF GAMMA RAYS". can anybody tell me what is meanning of word ATTENUATION.And why we are measuring it? i.e. what is the sigificance of measuring it?

It is well known that at times we do need explicit representations for the Dirac gamma matrices while doing calculations with fermions. Recently I found two different expressions for Majorana representation for the gamma matrices. In one paper, the form used is: \gamma_{0} = \left(...

Hi, Atmospheric gamma-ray extensive air showers are induced by pair-production interactions. The equation that governs pair production is: \gamma + \gamma = e^- + e^+ My understanding of the interaction is that a gamma passes "close" to the electric field of a nucleus. The nucleus acts...

what is the simplification of the following expression (in terms of gamma and\or other functions) ? \Gamma(xy) i tried the following : \Gamma(xy)=\int^{\infty}_{0} t^{xy-1} e^{-t} dt now let t^x = s => ( after some manipulation ) \Gamma(xy)=\frac{1}{x}\int^{\infty}_{0} s^{y-1}...

I'am not sure how to solve this gamma function \Gamma(5/4). any help ? sorry if this is in the wrong section.

Homework Statement A Gamma photon is used in order to dissociate deuterium into a proton and neutron. the binding energy is 2.22Mev anf the rest energies for the proton and neutron are 938Mev and 939Mev respectively. determine the minmum photon energy to achieve this. consider two cases: 1-...

questions about life of gamma ray particle question-are gamma ray particles unchanged after gamma ray burst 13 billion years ago? question-are changes detected not due to travel through normal space, scattering? changes due to dark matter/energy? question-positronium decay at end universe...

What is the physical process common to both the emissions of atomic x rays and nuclear gamma rays? is it photoelectric.. or the inverse.

Does anyone know of any properties in relation to adding two upper incomplete regularized gamma functions? i.e. can you write Q(a,z1) - Q(a,z2) = Q(a,X) ? where X(z1,z2) Extra information: a is a positive half-integer. Natski

I hav a random variable X which is gamma-distributed with scale θ and shape k, i-e X ~ gamma(k,θ); Now I have another variable, Y= 1+X, is Y gamma-ditributed? if yes what will be the scale and shape parametrs for Y, and what will be the expression for the probability density function of Y...

A random variable X is gamma distributed with a=3, b=2 (alpha/beta). Determine the probability that 1\leqX\leq2 The first thing I did was plug a & b into the gamma distribution formula 1/(b^a \Gammaa * x^(a-1) * e^(-x/b) Which I ended up with 1/16(x^2 * e^(-x/2) Which I then though...

Hi guys, Could someone show me how can I evaluate/measure the cross section of gamma+gamma --> electron + positron I'll be thankful for your help

Homework Statement a) A back-of-the-envelope calculation shows that in about 120 seconds the gamma ray burst released a total energy of about 10^48 Joule. How does this compare to the total energy that would be released by instantly vaporizing our sun into pure energy? (The sun's mass is...