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Gamma particles are electromagnetic radiation of high frequency and high energy per photon. Gamma rays are a form of ionizing radiation which are very hazardous to biological systems. They are produced by decay of high energy states of atomic nucleus. However, they can be created by other processes. Gamma radiation can ionizes and pass through matter by three different processes, the Photoelectric effect, Compton scattering and Pair production.

The photoelectric effect occurs when a gamma photon comes in contact with an electron which causes  transfer of energy.This transfer of energy causes the electron to be removed from the atom. The photoelectric effect is the mechanism for X-ray and gamma ray photons.

Compton scattering happens when an incident gamma photon loses enough energy to an atomic electron to cause its ejection with the remainder of the original photon’s energy emitted as a new lower energy gamma photon. This new gamma photons emission is in a different direction from that of the incident gamma photon; hence the term scattering. The probability of Compton scattering occurring will decreases with increasing photon energy.

Pair production happens when gamma energies exceeding 1.02MeV. The energy of the photon will be converted into the mass of an electron-positron pair through interactions with the electric field of the nucleus.  The mass of these two entirely will then be converted into two gamma photons.

Gamma radiation can have the most damaging effects. It causes damage at a cellular level due to its penetrating abilities. If exposed to gamma radiation, the gamma rays can cause radiation sickness, damage cell’s DNA and increase the incidence of cancer.

Kaon Oscillations

A pi- is sent onto a target producing neutral K mesons and ^ hyperons. Consider the component of the resulting K beam with momentum of p = 10GeV. What is the ratio between K1o and K2o at the production point and at l=10m from the production point? Assume no CP violation.

Alpha, Beta, and Gamma Decay

A certain hypothetical atom contains 68 protons and 87 neutrons in its nucleus and has an atomic mass of 154.2 atomic mass units, or amu (an amu is approximately 1.66 * 10^-27 kg). How many protons and how many neutrons will it end up with if it undergoes an alpha decay? How many if it undergoes a beta decay? How many if it unde

Physics: Gamma decay

Question: A hypothetical atom with negligible kinetic energy has a mass of 166 amu. It undergoes a gamma decay. The remaining atom has atomic mass which is less than that of the original by .0000135 amu. What is the kinetic energy and/or wavelength (whichever is more appropriate) of the emitted particle, assuming that the kineti

Nuclear Change and Nuclear Power

See the attached file. 1. Which of the following three types of radiation is the most penetrating? (a) Alpha particles (b) Beta particles (c) Gamma rays 2. Give the type and approximate amount of material required to stop each of the following: (a) Alpha particles (b) Beta particles (c) Gamma rays 3. Which rad

Decay of an unstable particle: Compute the speeds

An unstable particle at rest breaks up into two fragments of unequal mass. The mass of the lighter fragment is 2.81E-28 kg, and that of the heavier fragment is 1.31E-27 kg. If the lighter fragment has a speed of 0.803c after the breakup, what is the speed of the heavier fragment? Give answer as a fraction of the speed of light.

Positron and an electron collide producing 2-gamma rays

If a positron and an electron are both travelling at 0.450c in opposite directions as measured in a laboratory. They collide (and anihillate) producing 2-gamma rays, what is the energy of each of these rays? Express in MeV. (electron mc^2 = 0.511 MeV) Also, how fast is the positron travelling as viewed from the electrons refe

Nuclear Decay

1. Which radioactive emanations have a charge of -1? A) neutrons B) gamma rays C) alpha particles D) beta particles E) none of the above 2. Complete the nuclear equation by 86Rn220 à 2He4 + ______ writing the symbol of the missing particle: A) 84Po216 B) 84Po214 C) 82Pb218 D) 82Pb222

An object moving to the right at 0.8c is struck head-on by a photon of wavelength lambda, moving to the left. The object absorbs the photon (i.e. the photon disappears) and is afterward moving to the right at 0.6c. (a) Determine the ratio of the object's mass after the collision to its mass before the collision. (b) Does kinetic energy increase or decrease?

An object moving to the right at 0.8c is struck head-on by a photon of wavelength lambda, moving to the left. The object absorbs the photon (i.e. the photon disappears) and is afterward moving to the right at 0.6c. (a) Determine the ratio of the object's mass after the collision to its mass before the collision. (b) Does k

Energy Problems in Special Relativity

Part 1 The speed of light is 2.998 * 10 ^8 m/s. Find the ratio of the total energy to the rest energy of a particle of rest mass m0 moving with speed 0.26 c. Part 2 The K^0 particle has a mass of 497.7 MeV/c^2 . It decays into aPi- and Pi+, each with mass 139.6 MeV/c2 . Following the decay of a K^ 0, one of the pions is

Kinetic energy, rest energy and inelastic collisions of particles.

Can you show that the momentum P and the kinetic energy T of a particle of rest mass M can be related by: P^2=2TM+T^2. ____________________________________________ A particle of rest mass M moving with speed 'Beta-not' collides inelastically with (i.e. 'sticks to') a stationary particle of rest mass m. Find the speed of the

Gradient of potential energy w.r.t. coordinate equals minus the force.

1) Both the Coulomb law and gravitational forces lead to potential energies of the form [see the attached file for full equations and symbols] where [...] denotes [...] in the case of the Coulomb force and [...] for gravity, and r1 and r2 are the positions of the two particles. Show in detail that [...] is the force on particle

Mixed Graph and Trigonometry Problems

(See attached files for full problem descriptions) --- Problem Set 3: 1) Where does the graph of the equation y=mx+b cross the x-axis? A) b B) m/b C b/m D) - (b/m) E) -(m/b) 2)What angle does the line y=mx+b make with the x-axis? A) tan^-1(m/b) B) tan^-1(b/m) C) tan^-1(m) D) tan^-1(b) E) x/y 3) T

Intro Elementary Particles

See attached file for full problem description. 3.13 A pion traveling at speed v decays into a muon and a neutrino, pi^- --> mu^- + v_mu. If the neutrino emerges at 90 degrees to the original pion direction, at what angle does the mu come off? 3.14 Particle A (energy E) hits particle B (at rest), producing particles C_1, C

Quantum Mechanics Explained

This question is from the text book 'Quantum Mechanics' second edition by David J. Griffiths. There is one question and below the question there are equations which is needed to solve this problem. (See attached file for full problem description)

Gamma Wave Pattern

A pipe that is closed at one end is 0.5 meters long at 25o C. Sketch the standing wave pattern (loops with nodes and antinodes) for these three cases: (attached picture file) What is the wavelength of the 2nd overtone? If the air in the pipe is also at 25o C, what is the frequency of the 2nd overtone?

Threshold Kinetic Energy

What is meant by the threshold energy in a particle reaction? If the threshold energy in a particle reaction holds, what can you say about the motion of the particles in the centre of momentum frame? What does this imply about the motion of the particles in the original laboratory frame? Two photons of energies E1 and E2 coll

Nuclear Physics-Multiple choice questions

1. A hospital patient receives an x-ray dose of 0.5 m rad. What is the dose equivalent in sieverts? a. 0.5 m Sv b. .005 m Sv c. .05 m Sv d. 5 m Sv 2. Determine the identity of the nucleus X in the reaction 13C6 + n -----> X + gamma a. 13C6 b. 14C6 c. 14N7 d. 14N6 3. Identify the pa

Bernoulli's Equation Principles

An airplane flying at high altitude contains 100m^3 of air at STP(273 degrees and 1 atm). If a 1-cm^2 hole suddenly develops in the cabin wall, how long will it take for cabin pressure to drop by half?