Explore BrainMass


Beta particles are highly energetic and fast electrons or positrons that are emitted by certain types of radioactive nuclei. Beta particles that are emitted are a form of ionizing radiation known as beta rays. There are two forms of beta particles, ß+ or ß-, depending on if it is a positron or electron respectively.

ß- Decay or electron emission, is an unstable atomic nucleus with an excess of neutrons where the neutrons are converted into a proton, an electron and an electron-type antineutrino. Below is the process by the weak interaction.

n → p + e− + νe

Beta decay mostly occurs with neutron-rich fission by products produced in nuclear reactors. Free neutrons will also decay by this process.
ß+ Decay or positron emission is an unstable atomic nucleus with an excess of protons where protons are converted into neutrons, a positron and an electron-type neutrino. Below is the process.

p → n + e+ + νe

Beta plus decay will only happen inside a nucleus when the absolute value of the binding energy of the daughter nucleus is greater than that of the mother’s nucleus. Therefore the daughter nucleus is a lower energy state.

Beta particles are used to treat many health conditions such as eye and bone cancers. Beta particles are also used in quality control testing of thickness of materials. They are also used in positron emission tomography, PET scans.

Hamiltonian Spin

Please assist me in solving the following problems: Let's consider an ion (in an effective spin state corresponding to s = 1) at a crystal lattice site. As for the effective potential seen by the ion, assume spin Hamiltonian of the form: H = alpha*S^2_z + beta*(S^2_z - S^2_y) where alpha and beta are some real con

Problems in Statistical Mechanics

Please see the attachment for the formatted problem. 3. Consider again the lattice of N spin-1/2 particles in an external homogeneous magnetic field, where each particle has two possible states: spin "down" with energy e = 0 and spin "up" with energy e = 1/2". The microstate of the system is specified by the energy states of

Atomic Nuclear Decay & Radioactivity in Healthcare.

1. Discuss in detail, one way in which atomic nuclear decay takes place. What is the significance of atomic nuclear decay? Analyze the societal implications of using this process. 2.What are the various uses of radioactivity in healthcare? What are the future trends in healthcare with respect to the use of radioactivity?

Nuclear Reactions and Equations

Please see the attached file for the entire questions. Alpha, Beta, and Gamma Emitters When unstable nuclei decay, they generally decay into a more stable form. In the process, they emit radiation in the form of particles, particles, or rays. ? An Alpha particle is a helium nucleus, the symbol for which is . ? A

Electromagnetism: Force on moving charges in magnetic field.

A beta particle (high-speed electron) is traveling at right angles to a 0.43 T magnetic field. It has a speed of 2.5 107 m/s. What size force acts on the particle? ------ A magnetic field of 27 T acts in a direction due west. An electron is traveling due south at 7.0 105 m/s. What are the magnitude and direction of the for

Internal Energy for Nonrelativistic and Relativistic Gasses

(i) Show that the equation of state of an ideal gas is still PV = RT even when the gas is heated to such a high temperature that the particles are moving at relativistic speeds. (Hint: What feature of the partition function of the ideal gas determines the gas law?). (ii) Although the equation of state does not alter when the

Parallel Transport of a Vector.

Solve the parallel transport equations for a vector v = (v^r, v^theta) being transported around a circle of radius a about r = 0 in the 2D space with the metric ds^2 = dr^2 + (1 - beta)r^2 dtheta^2 where beta is a constant. Use the parametrization of the circle with theta, 0 <= theta <= 2pi.


Oscillations. See attached file for full problem description. 1) An undamped oscillator has period tau_0 = 1.000s, but I now add a little damping so that its period changes to tau1 = 1.001s. What is the damping factor Beta? By what factor will the amplitude of oscillation decrease after 10 cycles? Which effect of damping woul

Partition functions and probability.

Imagine a particle that can be in only 3 states with energies 1 eV, 2 eV, and 3 eV. The particle is in equilibrium with a reservoir at 300 K. a) Calculate the partition function for this particle. b) Calculate the probability of the particle being in the 2 eV state. c) How does the probability in part (b) change if t

Expansion coefficient and the Lennard-Jones potential.

Consider a classical particle moving in a one-dimensional potential well u(x). The particle is in thermal equilibrium with a reservoir at temperature T, so the probabilities of its various states are determined by Boltzmann statistics. (a) Show that the average position of the particle is given by x =&#8747;xe-&#946;u(x)


A radioactive source in the form of a metallic sphere of radius 10^-2 m emits beta particles at the rate of 10^10 particles per second. The source is electrically insulated. What is the time required for its potential to be raised by 4 V assuming 50% of the emitted beta particles escape the source ?

Distance Costs Decibels

(See attached file for full problem description) --- Distance Costs Decibels The general formula for the number of decibels corresponding to a change in sound intensity to relative to the former intensity is Part A Suppose that a sound has initial intensity measured in decibels. This sound now increases in intensi


Assume you are looking at a top view of an object of mass m connected between 2 stretched rubber bands of length L. The objects rests on a frictionless surface. At equilibrium, the tension in each rubber band is T. Find an expression for the frequency of oscillations perpendicular to the rubber bands. Assume the amplitude is suf

Calculating Nuclear Decay

I'm completely stuck on this problem: i) Determine the energy required to remove a proton from a 12C nucleus (in MeV) - For this one, I know that this is not alpha, beta, or gamma decay, so I don't know how I'm supposed to do it. And this one, ii) 2H and 3H nuclei undergo the following fission reaction: 2H + 3H --> 4He

Beta Identification

You are a health physicist and you find an unknown contaminant that proves to be a pure beta emitter. To try to identify the contaminant, you attempt to determine the maximum energy of the beta rays. You use a GM tube with a thin (0.1 mm, ?=2.7 g/cm^3) end window. You find that 1.74 mm stops all of the beta particles. The distan

Nuclear Chemistry

The reaction represented by the description "An atom of lead-210 decays by emission of an alpha particle" is: Question 3 The reaction represented by the description "An atom of copper-66 decays by beta emission" is Question 4 The reaction represented by the description "An atom of titanium-45 decays by positron emi

Radioactivity - Rate of beta decay

A radioactive source in the form of a metal sphere of diameter 10^&#8722;3m emits beta particles at a constant rate of 6.25 x 10^10 particles per second. If the source is electrically insulated, how long will it take for its potential to rise by 1 volt, assuming that 80% of emitted beta particles escape from the surface.