Scattering Definition and 821 Threads

Hi, so I am trying to build a cell counting apparatus using light scattering. The setup is a (green) laser shining through a clear bottle full of (Dicty) cells suspended in a stirred solution. The idea is to put a photodetector at some angle by the bottle; a greater cell density should result in...

Hi, I was wondering if someone could explain, in their own (simple) words, what the scattering spectrum of a nanomaterial is. For example, suppose we have a chain of several spherical nanoparticle. How would you interpret this graph...

from what I know: cross section in particles physics can be seen as throwing random darts on ballons on a wall, ie the wall is stationary. but if I want to work out the cross section of two laser beams at certain angles, the analogy above wouldn't hold would it? Since photons can never to...

Hi, before I start this is not coursework or any work attached to my degree but part of an internship at a neutron research facility at a level appropriate for Masters students and higer, so I felt it necessary to post it here rather than the homework section (sorry if I'm mistaken). I've been...

Take the scattering of photon and electron as example, we first figure out the amptitude for transition definte polarization, say f(ϵα(k),ϵα′(k′)) If the initial photon is unpolarized and the final polarization is not observed, we need to average the initial polarization and sum over the...

This is an assignment I'm doing that is due next month but I would like to make an early start because I find most of the materials in this assignment unfamiliar. The whole questions is composed of 5 parts, most of them I have a rough idea of but there are some bits and pieces I don't really...

Hi all. I am looking for an excellent textbook to be familiar with Quantum Physics and especially quantom scattering theory. Honestly my background is on the engineering part of Electromagnetic waves and I am seeking some explanations about Quantum theory. I appreciate ur attention in advance.

Some one please tell me how to calculate fractional shift of scattered wavelength of photon in terms of campton wavelength

I observed a strange phenomenon the other day which led me to ask this question. I was in Bahamas on a cruise, where it is very bright. This might have enhanced an otherwise more subtle effect. (OK, get the drinking jokes out of your system now... :-p) I was outside, right next to the...

Hello I actually wanted to posted this in the "Homework" section but it is currently working for me.. The problem is: Calculate the cross-section for the scattering of a 10 MeV alpha particle by a gold nucleus _{79}^{197}Au through an angle greater than (a) 10 degrees (b) 20 degrees c...

Is double parton scattering merely something of curiosity, or is it useful in the production of interesting particles (Higgs, top, B meson etc.)?

Homework Statement Gamma rays of energy 1.02MeV are scattered from electrons which are initially at rest. Find the angle for symmetric scattering at this energy. What is the energy of the scattered photon from this case? Homework Equations \Delta \lambda = 0.0243A (1 - cos \theta )...

Hey...i'm studying the reaction neutrino+antineutrino -> W(+) + W(-) but i don't understand which are the relevant f. diagrams at first order (semiclassic approximation). Does anyone know which are? thank you

Is there a difference between light scattering and radio wave scattering or do they operate on the same basic principles?

Homework Statement I'm working through the derivation of the Compton scattering crossection and I'm getting stuck partway through. More details below: Homework Equations The Attempt at a Solution So, I'm following along with Zee section II.8. We have two diagrams that contribute to order...

Hey, I am looking at the coupling hamiltonian for electrons in an EM field. In particular I'm interested in the inelastic scattering (this isn't the dominant part for inelastic scattering but it's confusing me). The part of the hamiltonian in the time/space domain that I'm interested in is...

Hi guys, i know that there are Feynman diagrams in condensed matter around. As far as i understood it they are used to calculate Green's functions but as we all know from qft Feynman diagrams can also be used to calculated scattering amplitudes...so, i wonder if there is a book around with...

Hi ! Sorry for a naive question from a biologist. I am making proteoliposomes within which a fluorescent probe, pyranine (lex = 455 nm, lem = 509 nm), has been trapped. I try to quality control my preparations using DLS (Dynapro, Proteinsolutions) and my concern is that whatever the...

Does the absorption cross section to scattering cross section ratio of an isotope vary with neutron energy or stay constant? I have heard that cross sections in general are inversely proportional to velocity (eg the fission cross section of U235 is about 1000 times higher for thermal neutrons...

Dose anybody know that is there any book whose content of scattering theory resembles that of Sakurai's and which is easy to follow. Thanks in advance.

I learned something about mie scattering in another thread. But I'm still perplexed, as what makes it different from scattering by air molecules (called Rayleigh scattering). But why doesn't the pattern cause polarization of light?

I heard from a lecture by Walter Lewin that the sky is blue because the chance of a photon of λ wavelength scattering is 1 / λ4 and blue's higher wavelength gives it a higher chance of scattering than red, making there more blue in the sky than red. This explanation might be incomplete, but this...

A single particle can behave like its interfering with itself by means of the following explanation (is it true or can you refute it?): Ballentine wrote in his 1970 paper "Statistical Interpretations of Quantum Mechanics": "As in any scattering experiment, quantum theory predicts the...

I initially would say Mie like "my/pie", but my advisor corrected me and said it was "Me". Yet, someone told me that is wrong and it is "my/pie". Is there any authority or unanimous agreement on its pronunciation somewhere?

Hi! I'm trying to derive the cross section of the bhabha scattering: \frac{d\sigma}{d\Omega}=\frac{e^4}{32\pi ^2 E^2_{cm}}\left[ \frac{1+cos^4\frac{\theta}{2}}{sin^4\frac{\theta}{2}}-\frac{2cos^4\frac{\theta}{2}}{sin^2\frac{\theta}{2}}+\frac{1+cos^2 \theta}{2}\right] I'm using the "toy...

Homework Statement What is the Bragg Scattering angle (i.e. the angle, in degrees, between the incoming incident beam and the reflected beam) for electrons scattered from a nickel crystal if their energy is 63 eV? The spacing between Ni Bragg planes is 0.215 nm. Give your result to 3...

Hey guys, I have some questions about deep inelastic scattering. I have read a bit about it, but don't really understand the theroy behind it. I know that it is a method to be able to study quarks inside, example with an electron hitting a proton target one can be able to study the quarks of...

What are the types of scattering techniques? And what have applied?like smal angle scattering...

I don't understand why in Bhabha scattering (e+ e- -> e+ e-) why there are only two leading order Feynman diagrams. It seems to me like there should be s, t, and u-channel diagrams. Could someone explain why I am wrong?

Hey all, This might seem like a strange/silly question but just humour me if you could... Is there any a-priori reason why a scattering phase shift should be linear in energy (energy of the incoming particle at infinity)? Are there examples of such shifts that have a different energy...

what is happening when you look at an object up close in sunlight and see a spectrum of different colors that appear as "dots"? I noticed this happens with most objects and the "dots" seem to change colors with different angles of incidence. can someone please explain what is going on?

Hi, In electron, neutron or photon diffraction from an atom,what does it mean when we say the waves scatter elastically from the atoms? What is an elastic scattering? Thanks,

Homework Statement I'm having difficulty with part C of this question: Homework Equations The Attempt at a Solution Using the above equations I correctly calculated the new wavelength of the photon after the collision and using the equations for the photon energies I...

"Scattering" by a potential When we have an unbound particle traveling past a potential well, what does it mean when it is said that the potential well will "scatter" the particle?

Homework Statement Complete this sentence. When doing Bragg scattering of x-rays off of NaCl, the first order K-Alpha peak has an energy that is ___________ the energy of the second order K-Alpha peak. Known Information It is known that the Intensity of the K-Alpha is greater than the K-Beta...

Homework Statement An electron initially at rest is scattered by a photon. a) Which scattering angle corresponds to the largest Compton shift and why? b) At what minimum photon energy can half of the photon energy be transferred onto the electron?Homework Equations \Delta \lambda = \lambda_2 -...

according to wiki's rutherford scattering experiment, "The fraction of particles that is scattered into a particular solid angle at a given direction relative to the incoming beam is called the differential cross section and is given by...

Howdy, I'm a computer programmer by trade, but I've got a project I'm working on for fun and could use some help with some of the physics details. I'm trying to get an algorithm that models the intensity 'I' of a monochromatic light at some distance 'd' from the source where there is a...

Hi I am trying to find information about the polarization state of a photon after it has been compton scattered. The photon is initially linearly polarized, has a known incoming energy, scattering angle and released energy. Say we ave incoming propagation along the z axis and E field...

A very simple question, but needs to know proper explanation. Why the neutron scattering from hydrogen is negative while deuterium and almost all other atom has positive scattering?

Homework Statement I have a (numerically calculated) cross section for a neutron scattering from a nucleus which looks like: 1) Am I correct in saying that there are three resonant peaks and these correspond to three different resonant particles? 2) If so, are the lifetimes of the...

Homework Statement I'm asked to draw a Feynman diagram for two neutrinos scattering from each other. Homework Equations None The Attempt at a Solution I don't really get the question so I don't know what I'm actually supposed to put in the diagram. Am I supposed to draw a diagram...

I've been reading a bit recently on Second Harmonic Generation and came across a supposedly separate technique called Hyper-Rayleigh Scattering (HRS). Can anyone explain the difference? I came across this paper, but didn't understand the difference...

Suppose I have a 2x2 Hamiltonian describing a conducting channel, as a black box. H_{Rashba}=\sigma_y k_x - \sigma_x k_y and also suppose I have an incident 2x1 wavefunction with up and down spin components, to this black box. What I am trying to do is to write a 2x2 reflection (or...

Assuming that the whole universe is electric charge neutral, there are neutral atoms, unbound electrons (which play the role in the last scattering), photons and decoupled neutrinos. So it seems to me there is no particle to "balance" the negative charge carried by the electrons. Did I miss...

Hi, I have a problem involving helicity. Homework Statement In a scattering e^{+}+e^{-} \rightarrow \nu_{\mu}+\overline{\nu}_{\mu} I have to determine for which values of the helicity of initial particles the cross section is not 0. Homework Equations The Attempt at a Solution On a...

Homework Statement In a relativistic collision between a photon and an electron, the recoiling electron has an energy of 40keV and the scattered photon an energy of 120keV. Find the energy of the photon before the collision, find the angles at which the photon and the electrons are scattered...

Hello everyone I've a question about the "time of the last scattering". My understanding is that this took place about 380,000 years after the big bang, and occurred when the universe cooled sufficiently to allow protons and electrons to form neutral hydrogens atoms. As a result, light was...

Homework Statement Hey. I've just conducted Rutherford's gold foil scattering experiment and am a little stuck on a part of the analysis. One of the objectives of the lab script is; 'To correct the counting rates measured in one plane for the fact that the foil scatters in a 3D cone'...

Homework Statement Suppose that an X ray has initial energy Eγ=100keV, and the incident (relativistic) electron has energy Ee=100GeV. Compute the final energy of the photon E'γ assuming the final direction of the photon makes an angle θ=Π with the initial direction. For solving this problem...