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, ...

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Thomson scattering at high frequencies

When studying the scattering of a monochromatic plane E&M wave by a point charge and after finding the differential cross section of the process I read a sentence saying "This result is valid only ...
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What happens to scattered light when intensity of light increases?

Does increasing the intensity of the incident light increase the proportion of the light that is scattered?
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67 views

Relativistic Scattering

When we work out the relativistic general two-body scattering in the CM frame (like two elementary particles producing two other P1 +P2 -P3 -P4) , the cross section is proportional to absolute final ...
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Electromagnetic scattering $T$-matrix in MATLAB

My problem with the inverse of the matrix T (in the photo) , the matrix consists of Bessel and Henkel functions in high order (the orders from 1 to 21), then the elements of this matrix arrived to ...
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126 views

Is the Air Blue? [duplicate]

Randall Monroe, a credible source in my opinion, says that the sky is blue because the air is: Normal light interacts with the atmosphere through Rayleigh scattering. You may have heard of ...
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36 views

What are ways to measure light scattering for a science fair project? And how exactly does scattering work?

How does scattering work? And why? I am still in middle school. I am doing my science fair project on scattering and so far the resources I found have either oversimplified it or made it in a way ...
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Baryon - Anti Baryon scattering

Is it possible, for a strong interaction of the above described type (baryon - anti baryon), to exist? $$B + \bar B \to \ldots $$ (Where $B$ is a generic baryon and $\bar B$ the anti-) Namely like ...
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39 views

Plane-wave wave function in 3D with vector potential

I was looking into a monopole scattering problem in 3D with magnetic potential. What would be the most general incident plane wave solution ? The way I see this is that I need to ensure that current ...
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15 views

Book Recommendation for relativistic scattering theory [duplicate]

I am looking for books on relativistic scattering theory with particular emphasis on application to experimental high energy physics. Does anyone have excellent recommendation?
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17 views

Why the total nuclear spin is only 0 or 2 for singlet s-wave scatting with $M_F=0$?

when I read the lecture of Feshbach resonance, the lecture on page 15 said that it want to find all s-wave molecules for $M_F=0$. It said when the two atoms are singlet, the total nuclear spin is only ...
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38 views

Why do higher frequency electromagnetic waves bounce of of smaller particles in the atmosphere but the lower ones dont?

I assume they have more energy but what is it more deeper and clearer than that that explains it?
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32 views

Why does vertical polarizer absorb the vertically polarized waves?

They explain that vertical wires serve as the secondary transmitter: the waves induce since oscillations of electrons in the wire effectively absorbing the wave. Ok, let's believe that wave is ...
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48 views

What does it mean that the Rutherford's cross section is infinite?

I'm studying elastic scattering and I read that the Rutherford's differential cross section is defined as: $$\left( \frac{d \sigma}{d \Omega} \right)_R = \frac{Z^2}{4} r_o^2 z^2 \frac{(m_ec / \beta p)...
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How does different particle size account for different colors?

I understand how objects have color in terms of absorption and reflection; however, in stained glass, various nano-particles can have different colors depending on the particle size. As described in ...
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70 views

How does one get the first few terms of the S-matrix expansion?

According to a set of notes I'm reading $$\langle p_f | S | p_i \rangle = \delta(p_f-p_i) + 2 \pi \delta(E_f-E_i) \bigg[\langle p_f | V | p_i \rangle + \cdots\bigg] \tag{1.29}$$ I don't understand ...
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64 views

Transmission and reflection amplitudes for delta potential Schrodinger equation

I hope this question is not too straightforward for this Q&A site. I have been reading a set of notes in which the transmission and reflection amplitudes for the delta potential Schrodinger ...
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47 views

Scaling dimension in Kerr/CFT

Let's consider the scattering of a scalar field around a Kerr-AdS Black Hole. In terms of the Kerr/CFT correspondence how can I get the relation between the scaling dimension and the mass of the field ...
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313 views

What is the difference between scattering and backscattering?

I sometimes hear people talking about scattering and backscattering, but I really cannot distinguish between the two? Can some one please explain what is meant by these two concepts from a physical ...
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50 views

Solution of Schrodinger equation for scattering

The following extract is taken from Appendix A of the following paper: http://arxiv.org/abs/0810.0713. Any solution of the Schrodinger equation with rotational invariance around the $z$ axis can ...
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1answer
55 views

General scattering theory

I have studied a bit of scattering/diffusion theory in an introductory course in quantum mechanics (the kind where the scattering potential is delta, box, and similar easy functions). But when the ...
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72 views

Massless scalar $\phi^3$ tree-level scattering amplitudes?

The CHY formula for massless scattering at tree-level can compute i.e. scalar, gluon and graviton amplitudes. For gluon scattering there are many other resources available to compute all kinds of tree-...
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Relationships between optical depth, $\tau$, and probability of being scattered

The optical depth is given by many as: $$ \tau=n_e\sigma_{cs}L $$ Where $n_e$ is the number density of the medium, $\sigma_{cs}$ is the scattering cross section and L is the linear extent of the ...
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Why can't I see the blue color scattered by the lower atmosphere of the earth?

I understand that the blue colour of the sky is because of the scattering of blue light by molecules in earth's atmosphere. The scattering appears to be happening from molecules that are far above in ...
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56 views

What is the formula for light emission from a point source in scattering media?

I'm trying to model the light output emitting from a point source somewhere in R3, and impinging on a fiber optic at distance r, that may be angled relative to the point source at some angle $\theta$. ...
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29 views

IBP Identities to solve differential equation

I am wondering if anyone has experience in using IBP( Integration by parts) identities in the evaluation of Feynman diagrams via differential equations? My question is that I can't seem to understand ...
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39 views

The $i\epsilon$ in non-relativistic scattering theory

When doing quantum mechanical scattering theory, we obtain the Lippman-Schwinger equation $$|\psi\rangle=|\psi_0\rangle+(E-H_0)^{-1}V|\psi\rangle$$ Here $\psi_0$ is the unperturbed wavefunction, $\...
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95 views

Photon-Photon-scattering (Feynman diagram)

The feynman diagram for the Delbrück-scattering (photon-photon-scattering) in the lowest order looks like as in the picture: But why is the following diagram equal to one of the upper three? There ...
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48 views

Quantum entanglement and Compton Effect

Suppose we generate 2 entangled photons (via a beam-splitter or similar apparatus). They have an arbitrary indeterminate initial frequency $\nu_i$. One of these photons is allowed to propagate through ...
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1answer
53 views

Scattering off of a bi-local potential

I am trying to figure out the scattering wave function for the following potential: $$V(x,x')=-A \phi(x)\phi^*(x')$$ Such that the SE can be written as $$[\frac{\hbar^2\partial^2_x}{2m}-E]\psi = A\...
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187 views

Rutherford scattering: Alpha particle scattering angle probability

An alpha particle (charge $q$) of energy $E$ is normally-incident upon a flat surface made of material with atomic number Z, number density n, and thickness d. What is the probability that it will ...
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99 views

Particle in a double delta potential, scatter states

I was studying the scatter states of a particle in a double delta potential given in this link: Double delta function well – scattering states But I dont understand how equations (20) and (21) were ...
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3answers
94 views

Finite square wall with $E > V_0$

I'm working through a problem for homework and feel as if there is a typo or I am confused. The problem is with a one sided finite square wall such as this: So the energy is more than $V_0$. I'm ...
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66 views

Proof of reflected and refracted waves being in the same plane as that of the incident wave and its projection on a planar interface

Please give a proof of reflected and refracted waves being in the same plane as that of the incident wave and its projection on an ideal planar interface between two linear, homogeneous, isotropic, ...
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133 views

What is the rigorous description of scattering in relativistic QFT?

The first conundrum is what picture of QM to choose, in order to describe such a scattering. Unlike in non-relativistic QM, in RQFT the three all-known pictures are not at all equivalent. The ...
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80 views

The second order scalar quartic field theory Feynman diagrams

I'm trying to find the second order Feynman diagrams for the scattering of a scalar phion, described by the Lagrangian $$ L = L_0 + L_I \\ L_0 = \frac{1}{2}[\partial_{\mu} \phi(x)]^2 - \frac{1}{2}m^2 ...
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1answer
64 views

Evidence for standard model description of neutrons

as I don't know too much about experiments I have the following question concerning the evidence about the quark constituents in neutrons. After a quick google investigation I found some sentences ...
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25 views

What's the electromagnetic boundary condition on axis for a 2D axisymmetric problem?

I have a basic but also kinda confusing question here. We know for electromagnetic scattering from a body of rotation symmetry it's possible to reduce the 3D problem to 2D axisymmetric ones, which ...
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Canonical treatment of thermalization of two gases at different temperatures

I'd like to understand the thermalization process when two gases of different species and different temperatures are allowed to mix in an insulated container, interacting only through an elastic ...
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1answer
53 views

minimum hyperbolic distance for Rutherford Scattering

I saw in a textbook that gave the minimum distance for a hyperbolic trajectory in Rutherford scattering is given by $$r_{min}= \frac{1}{4\pi\epsilon_0}\frac{Z_1Z_2e^2}{2E}\left(1+\frac{1}{sin\frac{\...
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1answer
165 views

Normalization of potential barrier solution

I don't understand a point in the solution attached to this barrier potential problem. Below equation 4.209, they say Assume first that the wave function on the right side of the barrier in the ...
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1answer
157 views

S-matrix in Weinberg QFT

I'm a bit confused by Weinberg's discussion of scattering. He defined the in and out states $|\Psi^{\pm}_\alpha\rangle$ with particle content $\alpha$ as states that transform under the Poincare group ...
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131 views

Pole in reflection/transmission coefficient and bound states

I was working on a scattering problem in a quantum mechanical system with Hamiltonian $$H_1=A^{\dagger}A=(-\partial_x+W(x))((\partial_x+W(x))).$$ One can show that a 'supersymmetric' partner to this ...
6
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4answers
824 views

Why is the sky blue: For a 3-year old [duplicate]

My nephew asked me yesterday why the sky was blue. I tried to explain it to him as best and as dumbly I could, but I failed. I tried to explain the concept of scattering of light using an analogy of ...
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50 views

Derivation of the dynamical master equation for collisional decoherence of a massive particle

I'm working on the problem of collisional decoherence of a massive particle interacting with an environment of light particles. The problem. I have some confusion regarding the derivation of the ...
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106 views

Rutherford scattering in Quantum Mechanics terms?

Rutherford scattering stands as the first evidence of atoms having the positive charge concentrated in a small nucleus. While the classical description of the phenomenon is satisfactory, it puzzles ...
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246 views

Converting between $\frac{d \sigma}{d t}$ and $\frac{d \sigma}{d \Omega}$

I'm performing some simulation where I require the integration of a cross section of the form $$\sigma = \int_{-s}^{0}dt \frac{1}{(t-\mu^2)^2} f(\theta,\phi)$$ where $s$ and $t$ are the usual ...
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2answers
188 views

Rectangular potential barrier

Take the usual rectangular potential barrier, that is: $$V(x)=0 \: \text{if} \: x<0 \: \text{or}\: \: x>a$$ $$V(x)=V_0 \: \text{if} \: 0\leq x \leq a.$$ I've looked at several notes and books ...
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87 views

Compton's formula for change in wavelength [closed]

I want to measure the shift in wavelength predicted by Compton's formula. I find that I cant measure a shift of less than 5% and that I also cannot measure at angles greater than 150 degrees. What is ...
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1answer
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Bragg Scattering of Thermal Neutrons [closed]

I'm currently reviewing Bragg scattering. The particular problem below has me slightly confused on whether I'm thinking about it correctly. Questions Is the problem below referring to the kinetic ...
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1answer
92 views

Lippmann-Schwinger equation and $T$ expansion

Lippmann-Schwinger equation, in operator form, is: $$ T=V+V\frac{1} {E-H_0+i \hbar \varepsilon} T=:V+V\Theta_0T, $$ where $H_{tot}=H_0+{V}$ is the hamiltonian ($H_0$ is the free particle hamiltonian ...