LOW-LEVEL BETA ACTIVITY MEASUREMENT OF SOLID SAMPLES USING PLASTIC SCINTILLATOR ANTICOINCIDENCE

Journal Article · Fri Nov 01 04:00:00 EST 1963 · Nucl. Instr. Methods

DOI:https://doi.org/10.1016/0029-554X(63)90369-0· OSTI ID:4096861

Mishra, U C; Varma, R K

An instrument consisting of a G-M counter shielded by a plastic- scintillator-cone and 15 cm of lead was designed giving a background of 12 counts per hour. The sample spread in an area of nearly 3 square centimeters can be counted in a nearly 2 pi geometry, with an overall counting efficiency, of about 15 percent for potassium-40 betas. Thus, thin solid samples of activity less than 10/sup -13/ curies per square centimeter can be measured in 4 hours sample counting time with about plus or minus 201% accuracy. The factor limiting the background is probably only the internal contamination of the counting system. A further reduction in background can be attained by using special low-level G-M counters. The instrument is ideally suited for pure beta emitters like strontium- 90 for which it was primarily developed, but it can also be used for beta-gamma emitters as described. The limitations in this case are discussed and preliminary results with different beta-gamma emitters are given. (auth)

• Research Organization: Atomic Energy Establishment, Trombay, India
• NSA Number: NSA-18-008662
• OSTI ID: 4096861
• Journal Information: Nucl. Instr. Methods, Journal Name: Nucl. Instr. Methods Vol. Vol: 24
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BACKGROUND
BETA PARTICLES
CONTAMINATION
GAMMA RADIATION
GEIGER-MUELLER COUNTERS
INSTRUMENTATION
LEAD
PLANNING
POLYMERS
POTASSIUM 40
PULSES
RADIOACTIVITY
RADIOISOTOPES
SAMPLING
SHIELDING
SOLIDS
SURFACES