Ultra-sensitive carbon fiber dosimeter

Abstract

A 20 mR (5.16 * 10 -3 C/Kg) full-scale carbon fiber dosimeter that provides a direct reading of low-level Gamma and neutron exposure in real-time. To attain this, the dosimeter utilizes an enlarged ionization chamber that has a cylindrical shape with an inside diameter at least 1 inch (2.54 cm), an outside diameter at least 1.1 inches (2.794 cm), an inside height at least 0.725 inch (1.8415 cm), and an outside at least 1 inch (2.54 cm). Moreover, the inner wall of the dosimeter's ionization chamber is lined with either a predetermined hydrogenous or non-hydrogenous material having different sensitivity to gamma ray and neutron exposure.

What is claimed is: 
     
       1. A highly sensitive carbon fiber dosimeter that provides real-time measurements of radiation exposure including gamma rays and neutrons, comprising: a tubular plastic barrel having an ionization chamber that provides the dosimeter with 20 mR full scale sensitivity to the radiation exposure, said ionization chamber having a cylindrical shape with an inside diameter of at least 1 inch (2.54 cm), an outside diameter of at least 1.1 inches (2.794 cm), an inside height of at least 0.725 inch (1.8415 cm);   said ionization chamber having an inner wall composed of a predetermined material having a predetermined sensitivity to the gamma rays and the neutrons.   
     
     
       2. The dosimeter of claim 1 wherein said predetermined material composing said inner wall of said ionization chamber is an hydrogenous material having a predetermined sensitivity to both the gamma ray and neutron components of the radiation exposure. 
     
     
       3. The dosimeter of claim 1 wherein said predetermined material composing said inner wall of said ionization chamber is a non-hydrogenous material having a predetermined sensitivity only to the gamma ray component of the radiation exposure.