Scattering is a term used in physics to describe a wide range of physical processes where moving particles or radiation of some form, such as light or sound, is forced to deviate from a straight trajectory by localized non-uniformities (including particles and radiation) in the medium through which they pass. In conventional use, this also includes deviation of reflected radiation from the angle predicted by the law of reflection. Reflections of radiation that undergo scattering are often called diffuse reflections and unscattered reflections are called specular (mirror-like) reflections. Originally, the term was confined to light scattering (going back at least as far as Isaac Newton in the 17th century). As more "ray"-like phenomena were discovered, the idea of scattering was extended to them, so that William Herschel could refer to the scattering of "heat rays" (not then recognized as electromagnetic in nature) in 1800. John Tyndall, a pioneer in light scattering research, noted the connection between light scattering and acoustic scattering in the 1870s. Near the end of the 19th century, the scattering of cathode rays (electron beams) and X-rays was observed and discussed. With the discovery of subatomic particles (e.g. Ernest Rutherford in 1911) and the development of quantum theory in the 20th century, the sense of the term became broader as it was recognized that the same mathematical frameworks used in light scattering could be applied to many other phenomena.
Scattering thus refers to particle-particle collisions between molecules, atoms, electrons, photons and other particles. Examples include: 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.The types of non-uniformities which can cause scattering, sometimes known as scatterers or scattering centers, are too numerous to list, but a small sample includes particles, bubbles, droplets, density fluctuations in fluids, crystallites in polycrystalline solids, defects in monocrystalline solids, surface roughness, cells in organisms, and textile fibers in clothing. The effects of such features on the path of almost any type of propagating wave or moving particle can be described in the framework of scattering theory.
Some areas where scattering and scattering theory are significant include radar sensing, medical ultrasound, semiconductor wafer inspection, polymerization process monitoring, acoustic tiling, free-space communications and computer-generated imagery. Particle-particle scattering theory is important in areas such as particle physics, atomic, molecular, and optical physics, nuclear physics and astrophysics. In Particle Physics the quantum interaction and scattering of fundamental particles is described by the Scattering Matrix or S-Matrix, introduced and developed by John Archibald Wheeler and Werner Heisenberg.Scattering is quantified using many different concepts, including scattering cross section (σ), attenuation coefficients, the bidirectional scattering distribution function (BSDF), S-matrices, and mean free path.
Homework Statement
A photon scatters in the backward direction (\theta= 180) from a free proton that is initially at rest.
What must the wavelength of the incident photon be if it is to undergo a 10.0% change in wavelength as a result of the scattering?
Homework Equations...
... if you consider something simple momentum conservation, like in the case of a bullet, if you consider the system of the gun and the bullet, the momentum is zero before and after the shot is fired.
same for collisions etc...
however when you consider something like a deflection in...
Hiya. I'm revising for a classical mechanics first year exam, and the lecture notes on central forces are less then ideal. I'm looking for a fairly simple treatment of the subject with especial regard to circular motion, bound and unbound orbits, binary systems, kepler's laws, distance of...
Homework Statement
Hi
1) I read the following article: http://pdg.lbl.gov/2005/reviews/passagerpp.pdf
On page 12 of the .pdf there is a figure, figure 27.8, which shows how a charged particle deviates from it's path when scattered by the Coulomb force that comes from the nuclei of the matter...
Homework Statement
How to square this : (Pi+m.c-Pf)^2 ?
Homework Equations
The Attempt at a Solution
I did : Pi^2 + m^2*c^2 + Pf^2...
but then I don't know the rest of the completion..
please help me..
Thank you in advance..
Okay, so I have two questions, both pertaining to the Compton Effect.
Homework Statement
Evaluate the maximum kinetic energy for a recoiling electron that is struck by a photon with momentum 0.04MeV/c
Homework Equations
Maximum Kinetic energy: E_{k} = \frac{hf}{1 + (mc^{2}/2hf}...
1. Are there possible (4th order)process of "decay of photon" \gamma\rightarrow 3 \gamma with one-photon initial state and 3-photon final state? Intuition tells me there are no such processes. But because of crossing symmetry of scattering amplitude one can argue that such processes should be...
Homework Statement
Not homework, just for fun. I want to derive Compton Scattering equations using Mandel-Stam variables as opposed to the way that I have done it in class using the usual energy and momentum conservation
Homework Equations
(p_\mu+p_{ei}_\mu)^2=(p'_\mu+p_e_\mu)^{2}=s
p is the...
hi, i want to know why scattering can occur when the light beam meet the particle, dust in atmosphere or molecules in water ..., but why not when they meet the glass surface and let the electrons in the glass surface be scattered? can anyone kindly help me, and tell me more about this ? thanks...
Problem
Determine the differential and total cross sections for scattering from a "hard
sphere" of radius R ("hard" means impenetrable).
Relevant Formulae
\sigma (\Omega) d \Omega = \frac{number \ of \ particles \ scattered \ into \ solid \ angle \ per \ unit \ time}{incident \ intensity}...
Hello, can anyone tell me the equation to the Mie scattering.
I have salt particles of a specific size, and I want to work out the Mie scattering of it.
Thanks a lot
From steve.
I am constructing a 'white line detector' to use on the underside of a robot. The crucial components are an ultrabright red LED and a light-to-voltage converter. My initial idea is to leave the LED as it is, i.e. unshielded. I have to light-to-voltage converter, which is a phototransistor...
Hello everyone,
First and foremost I would like to see if everyone's having a good day? (assuming you respond yes) Awsome! Secondly I was hoping someone would be able to help me understand how dielectrics work.
I don't need to know everything about dielectrics. I only need to know how...
Homework Statement
A beam of low energy protons is observed to scatter elastically from a target of neutrons. Sketch the variation of the differential cross section with the resulting scattering angle and comment on a characteristic feature of the strong force than can be deduced...
Homework Statement
A particle with mass m scatters off of the potential
V=A\delta(z) for -a \leq x \leq a and -a \leq y \leq a
V= 0 otherwise
Find the differential scattering cross-section using the Born approximation and show that in the limit where a goes to infinity the resulting...
Homework Statement
Particles are scattered (classically) from a paraboloid shape. The surface is given by the relation:
z = a \left(\frac{y^2+x^2}{R^2}-1 \right)
for x^2 +y^2 leq R^2 where a and R are constants. The particle is incident from z = -infinity with impact parameter s.
Show that...
Homework Statement
Particles of scattered off the surface of an ellipsoid given by x^+y^2+z^2/f^2 = R^2, where f and R are constants. Find the differential cross-section.Homework Equations
The Attempt at a Solution
Let s be the impact parameter. I can find s as a function of the scattering...
I have one doubt about Bhabha scattering which is scattering between one electron and one positron, two oppositely charged particles. Why should they scatter each other away rather than attract and eventually annihilate themselves, giving rise to the pair annihilation process? (This process is...
Hello experts,
I've had some fun reading the posts in the various forums, and now it's time for me to ask a question.
Is it possible to scatter light off of a BCS semiconductor such that the light can be considered to scatter from the coherent state of many Cooper pairs, rather than just...
Homework Statement
Updating the carrier momentum after scattering is most easily accomplished in the rotated coordinate system. The rotated x-axis is related to the original x-axis by x_{r} = Y_{\theta}Z_{\varphi}x where Y_{\theta} describes a rotation of {\theta} about the y-axis, and...
Hi , I got stuck on a point of griffiths' scattering problem on "the introduction to elementary particles"
Homework Statement
Consider the case of elastic scattering , A+B-->A+B , in the lab frame (B initially at rest) assuming the target is so heavy (mbc2 >> Ea) that its recoil is negligible...
Homework Statement
I have to simulate a two-level electron scattering process. 1000 electrons start in state i and over time, end up in state f. I need to plot the number of electrons in each state as a function of time.
Homework Equations
None.
The Attempt at a Solution
The probability...
Can anybody provide me with information on thomson scattering for someone who hasn't done electrodynamics? I find ones like http://farside.ph.utexas.edu/teaching/jk1/lectures/node85.html but I don't know anything about solid angles and the scattering cross section is confusing me. I'm...
I originally posted this in the homework section until I realized the homework section only covers through undergraduate courses. The course I am currently in is a graduate level Medical Physics course. So if you don't mind, here is the thread I posted in the homework section.
I am...
I am preparing for a Nuclear Physics test. One of the homework problems asks the following: Choose the proper neutron interaction type for each of the following scenarios and explain why. Interaction types: elastic, inelastic, (n, \gamma),(n,2n),(n, \alpha).
A. 10-MeV neutrons...
Homework Statement
A photon of wavelength \lambda enters an electron gas.What is the minimum number of collisions that could result in the photon being completely absorbed in the gas?
(a) \approx\lambda\frac{mc}{2h}
(b) \approx\lambda\frac{mc}{h}
(c) \approx\lambda\frac{2mc}{h}...
Homework Statement
A beam of \alpha-particles, of kinetic energy 5.3 MeV and intensity 10^{4} particle/sec, is incident normally on gold foil with thinckness 1 x 10^{-5} cm. (The density, atomic weight and atomic number of gold are 19.3 g/cm, 197 and 79 respectively.) A particle counter of...
Homework Statement
The fraction of 6.0 MeV protons scattered by thin gold foil, of density \rho=19.3 g/cm^{3}, from the incident beam into a region where scattering angles exceed 60 degrees is equal to 2.0 x 10^{-5} . Calculate the thickness of the gold foil using the result of the previous...
Homework Statement
50uA beam of 1MeV proton
Target = Iron of 0.05um thick
Calculate scattered current density at distance 5 cm at 20 degrees angle
Homework Equations
\sigma(E,\theta) = \pi*Z_{1}Z_{2}e^{4}(M_{1}/M_{2})/ET^{2}The Attempt at a Solution
I figured the probability of scattering to...
Hello,
I do a research concerning Mie scattering. The Mie formulae are angle dependent, but I need a function from which I'll get the scatterd angle (as a function of some dependent parameter), can someone please direct me in the right way ?
Homework Statement
If the maximum energy transferred to an electron during Compton Scattering is 50KeV, what is the wavelength of the incident photon?
Homework Equations
\lambda' - \lambda_{o} = h/(Me*c)(1-cos\theta)
The Attempt at a Solution
We know that the maximum energy...
I was reading section 24 of Peebles "Principles of Physical Cosmology" where he analizes the impact of scattering by dust at redshifts z < 100 on the cosmic background radiation for an Einstein-deSitter universe. I was disappointed to find out that at the end of the subsection he concludes that...
hi,
i am a new student here in this forums from uae and i am studing in uaeu my majore is general physics >>>
in this corse i have problem in nuclier physics in rutherford scattering >>>
can you help ma pleaseeeee the problem are :
firest one is :
Show that the distance of...
Hello,
The problem I have is trying to derive a formula for the compton equation, but instead of having the electron at rest, it is moving in the same direction as the incident photon. I've tried deriving it in the same manner as deriving it for an electron at rest (ie. I've simply made the...
\alpha particle of mass m is scattered by a nucleus of mass M. \Theta is the scattering angle of the \alpha particle in the LAB reference frame, and \theta is the scattering angle in the CM frame.
What is the relation between \Theta and \theta using conservation of energy and momentum?
I am...
[b]1. Homework Statement [/b
Robinett question
One of my homework questions in the Compton scattering section asks:
"Evaluate the fractional change in wavelength delta lambda/lamdba, for incident blue light and X-rays? It also gives the wavelength of blue light and X-rays.
I do not know what...
I got the answer of the hw, but still have question about it.
I need to calculate the scattering time μ = eτ / m. τ is the mean time.
the unit needs to be in cm^2 / V.S
I put the unit like this :
e = coulumb
τ = s
m = kg
then it's impossible to get the unit like that.
Then I'm...
Hello,
In Compton scattering, does the electron absorbs a photon and then emit another photon with another energy??
I couldn't understand how would the electron absorb a FRACTION of the photon's energy which is forbidden in QM.
Regards
Does anyone know a rough ballpark figure for the opacity of the Earth's atmosphere in the visible? Assuming an observer is at sea level looking to the horizon, I calculated the opacity due to Rayleigh scattering in the visible band, as shown in the attachment.
I don't really require a high...
Homework Statement
We are interested in the solution of the Schrodinger equation with positive energy E = h_^2k^2/2m for the potential V(x) = -v_0*delta(x). We take the scattering state under the form Ae^ikx+Be^-ikx for x<0, and Ce^ikx+De^-ikx for x>0
Find the scattering matrix S(k)Homework...
For processes of particle decay and inelastic scattering, quantum field theory (QFT) predicts well the probabilities of various final states for given initial states. Technically, this is described by the S-matrix, which is the unitary-evolution matrix describing the transitions from t=-infinity...
Homework Statement
A parallel beam of alpha particles with fixed kinetic energy is normally incident on a piece of gold foil.
a) if 100 alpha particles per minute are detected at 20 degrees, how many will be counted at 40, 60, 80 and 100 degrees?
b) If the kinetic energy of the incident...
Hi all.
Any someone recommend an introductory text on Inverse Scattering Transform and about solitons?
I am currently using "Solitons and Inverse Scattering Transform" by Segur nd Albowtiz, which I think is too advanced for me, an engineering student.
I have done a little research on the internet and I would like to ask my concept is correct or not.
1) Sky is blue
As the effect of rayleigh scattering is more effective for shorter wavelength, blue light scatter more than others (e.g. red). Furthermore, our eyes are more sensitive to blue...
1. Question
A cubic crystal of interatomic spacing of 0.24 nm is used to select
gamma–rays of energy 100 keV from a radioactive source containing a continuum of energies. If the incident beam is normal to the crystal, at
what angle with respect to the incident beam do the 100 keV...
Homework Statement
I need to derive the Compton scattering formula using Newtonian mechanics, I have it done in relativistic mechanics but can't get the Newtonian version.
Homework Equations
the solution to the relativistic equation is
1=mc^2(1/E2-1/E1)+cos(theta)
for Newtonian...
Homework Statement
n a Rutherford scattering experiment a target nucleus has a diameter of 3.5 10-14 m. The incoming has a mass of 6.64 10-27 kg. What is the kinetic energy of an particle that has a de Broglie wavelength equal to the diameter of the target nucleus? Ignore relativistic...