| 摘要 |
A detecting head assembly which is capable of simultaneously detecting radio-active emissions (such as beta particles) from a multiplicity of samples. The assembly includes a sample holder (1) defining a multiplicity of sample receiving zones (2) and structure defining a multiplicity of drift chambers (12). A beta particle emitted from a sample ionizes gas within the drift chamber (12) and negative ions are funnelled, by the application of an electric field, through holes (7) in a mask (6) part of the structure for collection by anode wires (4). The anode wires are isolated from one another by walls (11), the latter walls and structure being grounded and the sample holder being connected to a high negative potential. Cathode strips (3) cross-over the anode wires (4) to form crossing points (5) which detect negative ions passing through the respective holes (7). The effect of the electric field is to increase the gain of the detecting head assembly. The assembly is useful in the field of medical diagnostics and biomedical research for providing information relating to radio-active samples. |
