--%>

Nuclear Physics Homework Help

NUCLEAR PHYSICS (PHY555) HOMEWORK #1

1. Calculate the luminosity for a beam of protons of 1 µA colliding with a stationary liquid hydrogen target 30 cm long. Compare this to a typical colliding beam luminosity of ∼1034 cm-2s-1.

2. An imaginary accelerator consists of colliding beams of electrons and protons, each of 2 TeV total energy. What laboratory energy would be required to achieve the same center-of-mass energy if electrons collide with stationary protons? Repeat the calculation for beams of 2 GeV instead of 2 TeV.

3. Beams of electrons and protons, both traveling at almost the speed of light, collide. The electrons and protons are in bunches 2 cm in length in two rings of 300 m circumference, each of which contains one bunch. Each bunch contains 3x1011 particles, and the circulating frequency is 106=sec for each beam, so that 106 bunches collide with each other per second. Assume that the particle is distributed uniformly over cross-sectional areas of 0.2 mm2, and that this is also the area of the intersecting collision region.

a) Determine the luminosity

b) If the cross section for collisions is 10 µb, determine the number of scattering events per second that would be observed in a counter totally surrounding the intersection region.

c) Find the average x of electrons.

d) If the beam of electrons scatters from a stationary target of liquid hydrogen (density ≈ 0.1 g/cm3) 2 cm long, rather than with the circulating proton beam, find the number of scattering events and compare to part b).

4. The Rutherford scattering amplitude can be written as:

622_pic1.png

where V(x) is the scattering potential and q = p ?? p0 is the momentum transfer of the alpha particle (Z1e) to the target (Ze). Assume V(x) is the Coulomb potential of a nucleus shielded by an electron cloud. Use the form:

1793_pic2.png

where a is a length of characteristic of atomic dimension. Using this amplitude, and the fact that the target charge distribution is spherically symmetric to derive the Rutherford scattering amplitude in the form:

f(q2) = -2mZ1Ze2/q2 +?/a)2

Finally, rewrite this equation in terms of the kinetic energy of the incident alpha particle and the scattering angle.

5. Assume a probability distribution given by (x=j x j)

(4) x <= R : ρ(x) = ρ0

(5) x > R : ρ(x) = 0

a) Compute the form factor for this uniform charge distribution.

b) Calculate < x2 >1/2

6. Download and read the paper, "New measurements of the protons's size and structure using polarized photons", by John Arrington. Answer the following questions with no more than a paragraph of written response for each question.

a) What are the two methods being used to extract the electric and magnetic form factors, GE and GM?

b) Qualitatively, how does the extracted ratio GE/GM differ for these two methods?

c) What is the current explanation for the difference in the ratios between these two types of measurements?

 

 

 

 

   Related Questions in Physics

  • Q : Explain Ideal gas equation Ideal gas

    Ideal gas equation: The equation that sums up the ideal gas laws in one simple equation, P V = n R T, Here V is the volume, P is the pressure, n is the

  • Q : What is balmer series Balmer series (J.

    Balmer series (J. Balmer; 1885): An equation that explains the emission spectrum of hydrogen whenever an electron is jumping to the next orbital; four of the lines are in visible spectrum, and the remainder (residue) are in the ultraviolet.

  • Q : What is Ultraviolet catastrophe

    Ultraviolet catastrophe: It is the shortcoming of Rayleigh-Jeans formula that attempted to explain the radiance of a blackbody at different frequencies of the electromagnetic spectrum. This was clearly wrong since as the frequency rose, the radiance r

  • Q : What is neutral buoyancy What do you

    What do you mean by the term neutral buoyancy? Briefly illustrate it.

  • Q : Define Trojan points Trojan points : L4

    Trojan points: L4 and L5 are the two dynamically stable Lagrange points (that is, beneath certain conditions).

  • Q : Define Ohm or SI unit of electric

    Ohm: Omega: O (after G. Ohm, 1787-1854) The derived SI unit of electric resistance, stated as the resistance among two points on a conductor whenever a constant potential difference of 1 V generates a current of 1 A in the conductor;

  • Q : Atomic model which the Erwin

    Briefly state the atomic model which the Erwin Schrodinger creates?

  • Q : Define Landauers principle Landauer's

    Landauer's principle: The principle which defines that it doesn't explicitly take energy to calculate data, however instead it takes energy to remove any data, as erasure is a vital step in computation.

  • Q : What is Laplace equation Laplace

    Laplace equation (P. Laplace): For the steady-state heat conduction in 1-dimension, the temperature distribution is the explanation to Laplace's equation, which defines that the second derivative of temperature with respect to displac

  • Q : Define Zeeman Effect or Zeeman line

    Zeeman Effect: Zeeman line splitting (P. Zeeman; 1896): Zeeman Effect is the splitting of lines in a spectrum whenever the source is exposed to the magnetic field.