7D30.30 - Magnetic Deflection of Beta Particles

See procedure.
See procedure.
See procedure.
See procedure.
Code Number:
7D30.30
Demo Title:
Magnetic Deflection of Beta Particles
Condition:
Excellent
Principle:
Particle Interactions with Magnetic Fields
Area of Study:
Modern Physics
Equipment:
Survey Meter, Lead brick with hole, Large Neodymium Magnet, Strontium 90 Source, Amplifier & Speaker, Lab Jack.
Procedure:

Take the Strontium 90 source to one side of the lead brick with the hole in it.  This should collimate the particle stream to a single beam by having the particles travel through the hole in the brick.  Place the survey meter directly in front of the hole with the detector about 4'' away.  A very active count rate should be heard.  Move the pole of the Neodymium magnet in place directly above the particle stream.  The count rate should fall almost to background.  The particle beam can be reacquired by moving the survey meter in an arc to the right or the left depending upon which pole of the magnet is above the particle stream.  Typical bend of the particle beam is about 30 degrees. 

References:
  • Forrest I. Glick, "Convenient Absorbers for Beta Shielding Experiments", TPT, Vol. 10, #1, Jan. 1972, p. 39.
  • James F. Moore, "Beta Energy Using Modified Millikan Apparatus", TPT, Vol. 10, #1, Jan. 1972, p. 47.
  • W. Bolton, "The Effect of Magnetic Fields on Beta and Gamma Radiation", Book 3 - Atomic Physics, Physics Experiments and Projects, 1968, p. 63-64.

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