## Access

You are not currently logged in.

Access JSTOR through your library or other institution:

## If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Journal Article

# Energy Deposition Spectra of 14 C Beta Radiation in a Uniform Medium

L. A. Braby, W. C. Roesch and W. A. Glass
Vol. 43, No. 3 (Sep., 1970), pp. 499-503
DOI: 10.2307/3573224
Stable URL: http://www.jstor.org/stable/3573224
Page Count: 5
Were these topics helpful?

#### Select the topics that are inaccurate.

Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available

## Abstract

The effect of the gas-solid interface at the boundary of a proportional counter on the observed energy-deposition spectrum is not at present calculable. Therefore, the effect was measured in one case where it was practical to remove the solid wall from the detector by more than the range of the most energetic particle. A grid-walled proportional counter, 1 cm in diameter, with a removable ${}^{14}{\rm C}\text{-loaded}$ lucite wall was suspended at the center of a spherical vacuum chamber 1.2 m in diameter. The chamber was filled with a ${}^{14}{\rm C}\text{-loaded}$ counting gas, equivalent to lucite in mass stopping power, at a pressure which resulted in an "infinite" homogeneous medium for the 14 C beta particles around the counter. The energy deposition spectrum was recorded with and without the solid wall. For equal activity per unit mass in the solid and the gas, the dose must be the same with or without the solid wall. However, we found significant differences in the energy-deposition distributions. The presence of the solid wall caused more of the absorbed dose to be in the high-energy part of the spectrum with a compensating decrease at low energies. This result indicates that measurements of energy-deposition spectra should be made with gas-walled or other homogeneous detectors.

• 499
• 500
• 501
• 502
• 503