2012 Volume 61 Issue 7 Pages 365-371
Multi-wire chambers are used in the field of elementary particle and nuclear physics. A new multi-wire chamber with the narrow anode wire pitch pa of 1mm has been constructed. The chamber has an anode wire plane and a grid wire plane in parallel. Also wire directions of both planes are mutually perpendicular in order to obtain 2-dimensional information.
Main items on the design such as charge and electric field were calculated by analytical equations, not depending upon simulations by computers and some experiences. A new method called “modified charge division” for read out of signals has been developed. The signals were handled with only 4 pre-amplifiers. To confirm the properties of the chamber, we took a 2-dimensional image of a maple leaf as a sample by exposing to α particles out of an emitter 241Am.
The chamber can be operated, even if the pitch pa is so narrow. A vivid picture was obtained on the screen by using the chamber which was designed due to a few analytical formulae.