Questions tagged [scattering-cross-section]
A cross-section is the name given to a hypothetical unit of area (often in units of Barns) for measuring the probability of scattering events in particles collisions. DO NOT USE THIS TAG for a physical non-probabilistic cross-section of a macroscopic object.
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Definition of scattered particle?
Compare the number of scattered particles:
$N_s=Fa\int\sigma(\theta)d\Omega$
With the total number of incident particles:
$N_{in}=Fa$
Here, F is the flux of incoming beam, a the area. sigma the ...
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What is the spectrum of the Earth's albedo?
I was recently discussing climate change with a friend and was surprised (and embarrassed) to learn that the heat capacity of CO${}_2$ is not higher than that of nitrogen contrary to my assertions. ...
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How do particle scattering cross sections scale with energy in colliders?
How do particle scattering cross sections scale with energy in colliders?
Particularly photons, electrons, protons, and gold or lead nucleii?
(If necessary, break this into four separate questions.)
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What statistical test should I use?
I have two differential cross sections $d\sigma_{1,2}/dM$ ($M$ is some invariant mass) corresponding to different hypothesis. What I want is to calculate how well the appropriate experiment would do ...
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Where to find cross section data for $e^{-}$ + $p$ $\longrightarrow$ $p$ + $e^{-}$?
Where to find cross section data for $e^{-}$ + $p$ $\longrightarrow$ $p$ + $e^{-}$ ?
PDG's cross-section data listing does not include it.
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Physical interpretation of infinite total cross section
What does it tell us about a process, say A+B->C+D, if the calculated total cross section is infinite?
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Inelastic nucleon-nucleon cross section at LHC energies
I am trying to reproduce the number of participants $N_{part}$ in Pb-Pb Collisions at LHC using a Glauber Monte Carlo simulation, specifically aiming to reproduce the values given in Phys. Rev. Lett. ...
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Cross-section in relativistic limit: Fermi's golden rule still valid?
In order to calculate the cross-section of an interaction process the following formula is often used for first approximations:
$$
\sigma = \frac {2\pi} {\hbar\,v_i} \left| M_{fi}\right|^2\varrho\...
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Cross section fon non-collinear beams
If I have two collinear beams with opposite velocities the cross section is defined by the formula:
$\frac{dN}{dtdV}=\sigma \rho_1 \rho_2 |\underline{v}_1-\underline{v}_2|$
where $\sigma$ is the ...
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estimating ion collisions from Vlasov equations
Suppose you have a distribution function $ f_{\alpha}( \vec{r} , \vec{p} , t)$ obtained from Vlasov equations for a certain $\alpha$ species, say some ions.
Is there a rigorous way (in the domain of ...
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Quantum Field Theory cross sections integrals
Where can I find some examples of cross sections calculations in QFT done step-by-step? Those integrals are a little horror. For example - a simple scalar+scalar -> scalar+scalar at the tree level in ...