These are the photoelectric effect, compton scattering, and pair production. Compton scatering problem how to solve this large problem faster using the momentum system. In a compton collision with an electron, a photon of violet light. The debroglie hypothesis relates an objects wavelength to its momentum. Which one of the following occurs as a result of the collision. Problems are solved under lorentztransformationsoflength,time,velocity,momentumandenergy,theinvari ance of fourmomentum vector, transformation of angles and doppler effect and threshold of particle production. The photoelectric effect is a low energy phenomenon, and the interacted photons disappear just after they deliver their energy to electrons.
Physics sample questions royal college of radiologists. Photons, the photoelectric effect, compton scattering the purpose of the lecture. Compton effect the photoelectric effect and einsteins theories about light having a particle nature caused a lot of scientists to start to reexamine some basic ideas, as well as come up with some new ones. The first of these is the compton effect, named after arthur holly compton who received the nobel prize for physics in 1927 for its discovery. Compton scattering is one example of a type of inelastic scattering of light by a charged particle. Compton scattering diagram showing the relationship of the incident photon and electron initially at rest to the scattered photon and electron given kinetic energy. This identity equals 1, so it can be solved for hv. The xrays scatter from the electrons within the sample, imparting momentum to the electrons, which are initially at rest in the lab frame. The compton effect problem closed ask question asked 4 years, 3 months ago. Photons are far more penetrating than charged particles of similar energy. Chapter 6 deals with the special theory of relativity. Xrays with an energy of 300 kev undergo compton scattering with a target. The measurements were easy to explain for einstein if light is made up of particles with the energies. The compton effect compton scattering and gamma ray.
Solving one of them for the work function and substituting into the other one, we get 1 2max 1max. Probably the most important implication of the effect is that it showed light could not be fully explained according to wave phenomena. A, the wavelength of the scattered radiation is always of the order of 0. The corresponding momenta are p 1 e 1 c hf 1 h 1 and p 2 e 2 c hf 2 h 2 using f c. Solved problems in quantum mechanics mauro moretti. Theory of the compton effect michigan state university.
Compton effect page 2 results were controversial, but his work quickly triumphed and had a powerful effect on the future development of quantum theory. If the same surface is illuminated by the radiation of double the wavelength, the stopping potential is found to be 1. The compton scattering is inelastic and inchorent scattering of xrays and its value depends on the mole fraction of atomic species present in the sample and the compton intensity of. You will not need to work with x and ycomponents of the momentum separately in this problem.
Compton effect, increase in wavelength of xrays and other energetic electromagnetic radiations that have been elastically scattered by electrons. The other effect deals with the radiation emitted when a tightly bound electron from a heavy element is kicked out by a photon. This is the main difference between photoelectric effect and compton effect. From this point on, we can approach the problem in two ways, using either expression for the electronsenergy. On a circular conduit there are different diameters. Last time we talked about scattering in the limit where the photon energy is much smaller than the massenergy of. Jif103 physics 1 worksheet 2 solve compton effect problems w a v e p a r t i c l e d u a l i t y p r o b l e m s o l v i n g s e r i e s incident photon target electron at rest recoil electron scattered photon. Thus, the value of the energymomentum invariant is zero. The effect has proved to be one of the cornerstones of quantum mechanics, which. Solutions to problem set 9 december 12, 2006 1 problem 10. For the compton effect, conservation of momentum and conservation of energy have been combined into a partially solved equation based on the scattering angle of the photon. Find the frequency by putting in the appropriate constants. Photoelectric effect problems the physics hypertextbook.
In material physics, compton scattering can be used to probe the wave function of the electrons in matter in the momentum representation. It is a fundamental branch of physics that provides the underlying. Lecture 1 photons, the photoelectric effect, compton. The problems are from chapter 2 the quantum theory of light of the course text modern physics by raymond a. Energy loss mechanisms photoelectric effect compton scattering pair production interaction probability. Due to this effect, the incident gammaray photon is deflected with respect to its original direction. Photoelectric effect photoelectric effect is the process of emission of electron from the surface of metal when a photon of certain frequency is incident to a metal. This gives rise to characteristic xrays that can be used to identify. Plugging all the numbers in and solving numerically mathematica gives a. Physics stack exchange is a question and answer site for active researchers, academics and students of physics. When light was used to knock electrons out of solids, the results were completely different than expected from maxwells equations.
The problem was solved by klein and nishina in 1928 giving the correct quantummechanical calculation for compton scattering, the so called kleinnishina formula. Solved problems in the quantum theory of light ubc physics. Physics modern physics 7 of 26 compton scattering youtube. Inverse compton scattering similarly, the angle of incidence. Sketch the following graphs for the quantities involved in the photoelectric effect.
In principle, the problem is now solved by suitable rearrangement of these. Difference between photoelectric effect and compton effect. The compton effect or compton scattering in physics. The scattered radiation experiences a wavelength shift that cannot be explained in terms of classical wave theory, thus lending support to einsteins photon theory. Problems are solved under lorentztransformationsoflength,time,velocity,momentumandenergy,theinvariance of fourmomentum vector, transformation of angles and doppler effect and threshold of particle production. In order to establish the particle nature of radiation, it is necessary that photons. The scattered radiation experiences a wavelength shift that cannot be explained in terms of classical wave theory, thus lending support to.
The compton effect also called compton scattering is the result of a highenergy photon colliding with a target, which releases loosely bound electrons from the outer shell of the atom or molecule. Based on a lot of einsteins work including his special theory of relativity, physicists. Each detected gamma ray produces a pulse of electrons to the anode that in. In physics, compton scattering or the compton effect is the decrease in energy increase in wavelength of an xray or gamma ray photon, when it interacts with matter. Charles asman, adam monahan and malcolm mcmillan department of physics and astronomy university of british columbia, vancouver, british columbia, canada fall 1999. Compton scattering is an important effect in gamma spectroscopy which gives rise to the compton edge, as it is possible for the gamma rays to scatter out of the detectors used. What are the practical applications of the compton effect. Nuclear scattering also occurs, although the compton effect typically refers to the interaction with electrons. What information could we get out of such detections. After undergoing compton scattering, the gamma photon may undergo further scattering or absorption interactions with the shielding material andor emerge from the shielding material with diminished energy.
Experimental goals in this experiment you will measure. Chapters 7 and 8 are concerned with problems in low energy nuclear physics. The amount the wavelength changes by is called the compton shift. Here we are going to solve a simple problems basing on photo electric effect. A, the compton shift is very small, whereas for high energy photons with. Describe comptons experiment explain the compton wavelength shift describe how experiments. Photo electric effect problems and solutions iit jee and. These electrons will ultimately deposit their energy in the medium. Given here are solutions to 7 problems in the quantum theory of light. In order to solve this problem we are going to consider a series of approximations. Photoelectric effect provides evidence that energy is quantized. Plank solved the problem by postulating that em energy was emitted in quanta with.
In principle, the problem is now solved by suitable rearrangement of these three equations. Compton effect page 4 the positive xdirection with momentum 22 0 1 peeee c and energy 2 ee mc where m is the relativistic mass of the electron after the interaction. Problem 2 compton scattering a beam of xrays with wavelength 0. Thus, in contrast to ct, based on manipulation of projection information, compton scatter imaging csi, which records the scatter signal from a certain volume element, can be done. Describe the physical phenomena that led to quantum concepts.
Compton scattering is the main focus of this experiment, but it is necessary to understand the interactions of high energy, electromagnetic photon radiation with materials in general. Calculate the discharge and mean velocity at the outlet profile see fig. Solve for beta in terms of the ground state using momentum conservation. Inverse compton scattering also exists, where the photon gains energy decreasing in wavelength upon interaction with matter. Solve for the excited state using energy conservation. The compton effect, on the other hand, is a midenergy phenomenon, and the interacted photons are scattered by the electrons. In this compton effect interaction, the resulting kinetic energy of the electron is a e 0, b e, c e 0. These exercises have been given to the students during the past examinations. Description of photoelectric effect followed by worked example of determining the kinetic energy of ejected electron. When a radiation of certain wavelength is incident on a metallic surface, the stopping potentially is found to be 4. Compton scattering is an example of inelastic scattering of light by a free charged particle, where the wavelength of the scattered light is different from that of the incident radiation.
How can we detect galaxy clusters at high redshift. Quantum mechanics quantum mechanics is a quantum theory that supersedes classical mechanics at the atomic and subatomic levels. Compton effect is important because it cannot be explained by classical mechanics and shows that it is a particle effect. When solving numerical problems in the quantum theory of light it is useful to note that the product of. In this video i will show you how to find the wavelength of the scattered photon using the compton scattering equation.