The cross-section tag has no wiki summary.
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List of cross sections?
Sometimes I need to look up a certain cross section, say the inclusive Z production cross section at $\sqrt{s}$ = 7 TeV. Is there a place where 'all the' cross sections are tabulated ...
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Parton Distribution Functions, average cross section of the nucleon
Say we are given the scattering cross section for neutrinos from $d$ and $\bar{u}$ quarks as $\frac{d\sigma^{d}}{dQ^2}=\frac{G_F^2}{\pi}$, $\frac{d\sigma^{\bar{u}}}{dQ^2}=\frac{G_F^2}{\pi} (1-y)^2$, ...
2
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1answer
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Why is the total interaction cross section larger for incident particles with lower energy?
The cross section of a nuclear interaction is a measurement of the probability of that interaction occuring. These probabilities are typically presented in terms of barns ($10^{-28}$ m$^2$) as a ...
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QFT: differential cross section from center of mass to lab frame
I have the following process: two ingoing particles, a photon hitting a nucleus, and two outgoing particles, the nucleus and a pion. I have computed $|M|^2$ and the differential cross section in the ...
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Literature value of forward-backward asymmetry on the Z resonance?
I did a Standard Model calculation and I want to compare my answer to a measured value.
Does anyone know the literature value for the forward-backward asymmetry $\frac{\sigma_F - \sigma_B}{\sigma_F + ...
1
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1answer
151 views
Integral in Peskin and Schroeder
I'm having a bit of a slow day, and can't see how to do the following integral in Peskin and Schroeder (page 107 for anyone with the book). We've derived in the centre of mass frame the integral over ...
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1answer
161 views
SUSY, ways to boost Chargino/Neutralino production?
Does anybody know a good reference that works out the equations for the Chargino/Neutralino production cross section in SUSY? I'm trying to understand if there are any tricks for boosting the ...
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1answer
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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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1answer
79 views
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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Matrix element squared for up + antidown -> photon + W boson? [closed]
I am in trouble… I am a master student (first year) in theoretical particle physics and I have been working for several months on the calculation of the total cross-section at leading order for the ...
1
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1answer
135 views
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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0answers
149 views
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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2answers
181 views
Where to find cross section data for e- + p -> p + e-?
Where to find cross section data for e- + p -> p + e-?
PDG's cross section data listing does not include it.
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2answers
293 views
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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0answers
42 views
What sources can you recommend to understand the basics of the Coulomb interaction of particles [closed]
Maybe it's not the best place for this issue yet.
I am in graduate school. Field of knowledge of my supervisor - quantum physics - or rather, he examines the interaction of particles. Sources which ...
5
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1answer
173 views
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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1answer
540 views
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| ...
5
votes
1answer
165 views
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 ...
3
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1answer
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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 ...
4
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2answers
464 views
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 ...
