Scattering: Cross-Sections and the Born Approximation · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

What scattered particles say about the target

Science · Quantum & Modern Physics · ages 23-24
Name ______________________   Date ____________

  1. In the Born approximation, the amplitude is what of the potential?

    • Its exact copy
    • Its unrelated neighbor
    • Its Fourier transform

  2. What does a scattering experiment measure?

    • The color of the target
    • Counts of particles deflected into each direction
    • The age of the beam

  3. The scattering pattern maps the shape of the target potential.

    Circle one:   True   False

  4. A sharp feature appears at one angle. How do you read it?

    • As dirt on the detector, always
    • As structure in the potential showing through the transform
    • As proof of no potential

  5. How do you build the differential cross-section from lab quantities?

    • Counts divided by beam flux and solid angle
    • Flux times angle, ignoring counts
    • Counts plus flux plus angle

  6. The potential is strong. Which treatment do you reach for?

    • The Born approximation anyway
    • No treatment at all
    • A partial-wave treatment

  7. A report quotes a Born amplitude for a strong potential with no checks. What is missing?

    • More decimal places
    • A reason Born applies, or a partial-wave treatment instead
    • A longer title

  8. Two targets give different patterns under Born. What do you conclude?

    • Their potentials differ in shape
    • The beam changed color
    • Patterns never reflect targets
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Answer key

For grown-ups. Fold this page away before handing over the rest.

What scattered particles say about the target W1-mt_xmN9KDfSp7-s1

  1. Its Fourier transform · Born turns the potential into its transform.
  2. Counts of particles deflected into each direction · Fire a beam, count what bounces where.
  3. True · Pattern in, shape out, through the transform.
  4. As structure in the potential showing through the transform · Features in the pattern mirror features in the shape.
  5. Counts divided by beam flux and solid angle · Counts per flux per angle.
  6. A partial-wave treatment · Strong scattering needs partial waves.
  7. A reason Born applies, or a partial-wave treatment instead · Strong needs justification or a better method.
  8. Their potentials differ in shape · Different patterns mean different shapes.
Worksheet · LightMySky