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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$hh \to hh$ scattering
I'm trying to compute the double Higgs scatter in QFT framework. Is it correct if I use the scalar propagator for this process?
Also I've found that I've four possible diagrams: the three $s,t,u$ ...
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Neutron double differential capture cross section
Can one define what is the double differential capture cross section for a neutron, and how one would construct an experiment to calculate the double differential cross section as a function of energy ...
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Calculating Scattering matrix of a nuclear fusion reaction using Fortran
I am trying to find out the $S$-matrix elements for the reaction:
$${}^{19}\textrm{F} + {}^{208}\textrm{Pb}. $$
The model followed is Direct reaction model where the optical potential is:
$$ V_{op}(r) ...
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What is the difference between the center of mass energy of partons, and the invariant mass of the particles after a collision?
In a paper about the Atlas experiment (https://arxiv.org/abs/2103.01918) differential cross sections of $pp→ZZ→4\ell$
are being presented. However these cross-sections are functions of the invariant ...
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feynman scalar integral with on-shell condition
There are many integration written down in the standard QFT textbooks for scalar integrals in the computation of matrix elements. For example, in Peskin and Schroeder, we see
$$\int \frac{d^d \ell_E}{(...
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Differential Cross Section and Factor of $\pi$
I hope this is not a double-post, but the other threads couldn't help me:
In my calculations of the differential cross section $\frac{d\sigma}{d\Omega}$, I am always a factor $\pi$ lower than the ...
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Why does the stimulated emission cross section decrease with the refractive index?
The stimulated emission cross section decreases with the refractive index. Cannot understand why ? Can anyone give a physical explanation ?
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What is a cross section, really? [closed]
Upon looking at different resources, there is a common definition of a cross section (in the context of QFT) to be the probability that some scattering process occurs. For example, here is a ...
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Physical mechanism of $s$-wave neutron resonances in nuclear physics
In this answer by Arturo don Juan, and also, in section $7.8$ of Sakurai's Modern Quantum Mechanics, it is argued that resonances in the scattering cross-section at certain energies are due to the ...
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Inverse muon decay on Mandl shaw- Help on $W$ boson propagator
Hello, I cannot understand why here the other term of the propagator of $W$ boson $k^{\alpha} k^{\beta}/m_{W}^{2}$ is not present, and how/if this absence is linked to the fact that we neglect terms ...
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Reducing Inelastic Electron-Proton's Scattering Cross Section to Rosenbluth's Formula
I'm currently studying electron-proton scattering from Halzen & Martin's book (Quarks & Leptons : An Introductory Course in Modern Particle Physics). I found that the cross section for the ...
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Scattering cross section for distinguishable particles
I am reading Quantum Mechanics book by N. Zettili (2nd ed.) and encountered something confusing in the chapter of scattering theory, section 11.5: scattering of identical particles.
This is the ...
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Can the Moller cross-section be calculated using a two-particle potential?
Can the Moller scattering cross section be calculated with a two-particle potential?
The Feynman prescription for scattering two electrons, using perturbation theory (Weinberg QTF Vol1) involves ...
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Another "real vs virtual particle" one: calculate the full diagram or $\sigma \times \mathrm{BR}$?
I have recently been forced to think about something I always thought that I understood but that, in reality, I could not be more confused about.
Suppose I want to study the LHC prospects for ...
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Why is there a *minimum* energy for a particle to be captured in a $r^{-3}$ potential?
I was stuck in a central force problem from David Morin's Book "Introduction to Classical Mechanics".
The problem states that suppose there is a particle of mass $m$ moving under the ...
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