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).

Basically scattering phenomena, an essential tool in our understanding of microscopic physics - the physics of molecules, atoms, nuclei and elementary particles, refer to interactions between two classes of objects, such as molecules, atoms, electrons, photons and other particles.

  • For example: cosmic ray scattering in the Earth's upper atmosphere; particle collisions inside particle accelerators; electron scattering by gas atoms in fluorescent lamps; and neutron scattering inside nuclear reactors.
  • If the interaction potential between two types of objects is not precisely known, a scattering experiment gives us the opportunity to extract information about the interaction potential.
  • Depending on the state of the final-state particles scattering phenomena can be conveniently classified into the following processes.
    $(a)~$ Elastic scattering $~~~(b)~$ Inelastic scattering $~~~(c)~$ Rearrangement or breakup or reaction
  • Scattering theory is a framework for studying and understanding the scattering of waves and particles.
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Optical theorem and conservation of particle current

The optical theorem $$ \sigma_{tot} = \frac{4\pi}{k} \text{Im}(f(0)) $$ links the total cross section with the imaginary part of the scattering amplitude. My lecture notes say that this is a consequence of the conservation of the particle current.…
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Mie scattering intensity and spherical particles on

I am running an experiment where I shine infrared light on (almost) spherical particles on the micron scale (PM2.5 - PM10). I then look at the (90 deg) scattering properties to try and size the particles. I am looking for the theory of Mie…
l3win
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regarding the infinite cross section in Rutherford scattering

The differential cross section of Rutherford scattering blows as $\theta\rightarrow 0$. People express this fact as "The Coulombic potential is of long range". But I am seeing the opposite: $\theta \rightarrow 0$ is when the incident particle is not…
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What would Rutherford scattering be like off a "plum pudding model" atom?

Qualitatively, for a plum pudding model atom (where the positive charge of each atom is even diffused throughout the volume of the atom) I think that the deflection of incident alpha particles would be caused by the electrons and not the positive…
NeutronStar
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Is it possible to have colorful foams?

As we know foam is white regardless of the color of the soap or shampoo. ... the foam in its entirety looks white because when light enters the soap solution, it must pass through a number of tiny soap bubbles, i.e., a number of surfaces. These…
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Compton Scattering in Substances Other Than Graphite

When reading about Compton scattering I see the following figure: It shows that as a function of scattering angle the scattered photons lose energy and therefore have a longer wavelength (lambda prime). There are some number of scattered photons…
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What type of matrices do we mean by $I_{D2}$ and what is Chandrasekhar decomposition?

Suppose that $A_{2\times 2}$ is a hermitian matrix, so it has real eigenvalues $\lambda_1$ and $\lambda_2$ and corresponding orthonormal eigenvectors $\underline u_1$ and $\underline u_2$ and we know it can be written as the sum of two $rank-1$…
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Concerning Mie scattering and phase function dependance

In general, scattering intensity is written as $I = I_{0} \frac{\pi a^2 Q_{sca} P(\theta)}{r^2 4 \pi}$ It is also written as $I = I_{0} \frac{i_1 + i_2}{2 k^2 r^2}$ I am sort of confused, given the expressions of $i_1$ and $i_2$, is the phase…
l3win
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Impact parameter in scattering process

Let's consider classical two body scattering process. Is the impact parameter the same in the laboratory and inertial frame of references?
zoroastra
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Why are there oscillations in small angle scattering log-log plot?

In a log-log graph of diffused intensity I function of q (diffusion vector) you're supposed to get a linear function which slope equals the fractal dimension of the system you're studying. I get a linear slope but there are many big oscillations…
sokse
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Is there an upper limit to wavelength and particle size in the Mie Scattering solution?

I figure that Mie scattering is best for finding the scattering when the wavelengths are between 1/10th to 10x the particle diameter. However, is there an upper limit to this? If I send 2.8cm microwaves into a 10cm sphere, will it scatter according…
DarkLightA
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A question regarding a minus sign in the derivation of Rutherford's scattering formula

In the derivation of Rutherford's scattering formula, for example, this one here or this one here, we conclude that: $$\frac{db}{d\theta} < 0,$$ i.e., as the collision parameter increases, the scattering angle decreases. The thing that bothers me is…
user20250
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What are the criteria to have rutherford backscattering?

Assuming there is an incident beam(i.e. $p$ or $\alpha$) and a target. How can I be sure if a rutherford backscattering will take place? I know that for high $Z$ it more likely to happen as well as for higher beam energies. Is there a…
Thanos
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In Rayleigh scattering do the frequencies scattered correspond to the discrete energy level transitions available to atmospheric particles?

I have read that for Rayleigh scattering the photons are absorbed by the atmospheric particles then re-emitted (albeit very quickly) and the shorter wavelengths scatter better which is why the sky is blue. Am I right in saying that the sky is blue…
tomd7824
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Integral convergence in scattering problem

Consider the scattering of a particle by a central time-independent potential $V$, that is limited to a finite region in the space. the hamiltonian is $H = H_{0} + V$. Using the Moller operators, we can express the state of the particle at time $t =…
AlfredV
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