Questions tagged [scattering]
Scattering is a general term for several physical processes in which radiation of some sort changes direction due to an interaction with a particle. Scattering can be classified by the type of radiation (ie, electromagnetic, x-ray, neutron), or by the relative sizes of the wave and the particle (ie, Rayleigh, Mie, geometric).
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Cross section normalization in $2 \to 2$ scattering
Consider Compton scattering $$p_1 + p_2 \to p_3 + p_4$$ in the laboratory frame. According to Quantum Field Theory and the Standard Model by Schwartz, the relation between the differential cross ...
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Scattering probability distribution for $2 \rightarrow 2$ scattering
Consider a 2-to-2 particles scattering process (treated in second quantization) of particles with the following $4$-momenta:
$$p_1 + p_2 \rightarrow p_3 + p_4.$$
The probability measure associated ...
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Positive values of Mandelstam variable $t$
Is it possible for the Mandelstam variable $t$ to reach positive values in the quasielastic charged current neutrino-neutron scattering?:
$$\nu_{\mu} + n \rightarrow \mu^- + p$$
(don't assume that ...
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Computation of scattering cross section using Dirac equation
The differential cross section formula of the scattering of an electron on a nucleus are known to coincide when computed using either classical mechanics approach (Rutherford) or the Schroedinger ...
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Understanding derivation of quantum differential scattering cross-section [duplicate]
I've been trying to understand quantum scattering, but I think I am not very clear about the full picture in the derivation of differential cross-section below. In Modern Quantum Mechanics by Sakurai, ...
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When is the 3D Dirac delta function a good approximation for scattering?
When discussing X-ray or neutron scattering, it is usually assumed that the scattering potential is of the form
$$V_{\mathrm{eff}}(\mathbf{r}) = \sum_i b_i \delta^3(\mathbf{r}-\mathbf{r}_i)$$
with $...
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Confused about derivation - electron gas with binary collisions and impurities scattering
I am confused about a derivation for the behaviour of electrons in a conductor with binary collisions, and scattering due to static impurities. The derivation begins as follows:
The distribution ...
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Formula for a moving Schrodinger gaussian wave packet in three space dimensions [closed]
I am trying to time evolve quantum systems in the presence of a gravitational potential. To do this I need a free localised 3+1 dimensional wave packet with velocity so that I can perturb with a weak ...
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Why rainbow appears only after rainfall? [duplicate]
This is a silly question I know but I need a good logical scientific answer for this to quench my thirst of this doubt
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Why do discussions of classical EM scattering use scattering cross-sections instead of scattering amplitudes?
In every discussion of classical electromagnetic scattering that I've read - e.g. Jackson and Wikipedia (1 and 2) - the primary quantity that is used to quantify EM scattering is the differential ...
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General formula of glancing collision to classical scattering theory?
I encountered this . It takes some time for me to find that it is called glancing collision, well my language doesn’t has. What i interest isn’t the solution of the picture, but generalized ...
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Conventions in spinor-helicity formalism: are Elvang & Huang using angle brackets for left or right-handed Weyl spinors?
So, I'm reading about the spinor helicity formalism. In some references, I see angle brackets referring to left-handed (dotless) spinors. For example, Cheung writes (equation numbers in this post ...
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QFT Scattering: Perturbation Theory v.s. LSZ Reduction Formula
Context
It is well known that $S$-matrix could be computed in the following two ways:
Calculate in interaction picture Perturbatively.
Use the LSZ reduction.
To be specific, we have the math ...
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Fermi's Golden Rule in Two-Body Decay (Thompson)
I don't have enough reputation to add a comment to the original thread Interpretation of the lorentz-invarient transition rates (LI Fermi's Golden Rule), so I hope it's okay to ask a related ...
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Why does the straight-line approximation work for X-rays but not for waves with larger wavelengths?
In many imaging methods, such as X-ray CT, wave propagation is often modeled using the straight-line (ray) approximation. This works well for X-rays, partly because their refractive index is extremely ...
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