Measurements of the alpha particle induced current in metal foils

We have investigated the use of a 1.3 mCi 244Cm source as a reproduction of a lost α particle flux from high temperature fusion plasma. The purpose of the experiment was to allow the testing of thin-foil Faraday collectors as a lost α particle diagnostic. Many sets of measurements were made: the first with a single thick Al sheet and subsequently with a thin (2.5 µm) Ni foil backed by a thick Al sheet under varying conditions. The measurements were made with a commercial Keithley picoammeter and with a custom built high precision current integrator. Measurements were made at pressures between 1 mTorr and atmosphere. At higher pressures, above 1 Torr, the measured current was greatly exceeded by the predicted current. At lower pressures, less than 0.1 Torr, the measured current was observed to be in rough agreement with the expected current. A new technique to measure pressure in the regime of 1 to 50 Torr with an accuracy of about 1% at the lower pressures is explored.

Name thesis:degree_name

Master of Science (M.S.)

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Physics

Grantor dc:publisher

Colorado School of Mines. Arthur Lakes Library

Year dc:date.issued

2017

Author dc:creator

• Steward, Brian

Advisor dc:contributor.advisor

• Leach, Kyle

Committee members dc:contributor.committeemember

• Ohno, Timothy R.
• Cecil, F. Edward

Statement dc:rights

• Copyright of the original work is retained by the author.

Language dc:language.iso

eng, English

Identifier

T 8221

OAI identifier oai:identifier

oai:repository.mines.edu:11124/170678