Gas microstrip chambers (MSGC's), invented in 1987 by A. Oed, represent a new type of gas avalanche chamber wherein the anodes, instead of being freely suspended as in a wire chamber, are thin strips firmly attached to a solid support, or substrate. The narrow (~10 micron) anode strips lie in a plane, alternating with the wider cathode strips. The anodes are very closely spaced, typically about 200 microns (the "pitch"), a spacing that normally would be impossible in wire chambers, because of electrostatic instabilities.
A very good space resolution is the consequence of such small spacing, with a resolution less than 30 microns having been achieved. Other consequences are very high rate capability, and time resolution, relative to conventional wire chambers.
Although improvements in the design and performance of these devices are constantly occurring, they are already very much part of designs for present and future experiments (e. g. the LHC experiments at CERN).
An even newer type of chamber, the microgap chamber (MGC), is related to the MSGC, but the anode and cathode are no longer coplanar: the anode sits on a thin, insulating pedestal only a few microns above the cathode. In this device, the anode-cathode spacing is even smaller than in the MSGC, resulting in much faster time response and rate capability (~10x ).
The MSGC and the MGC have certain potential advantages over silicon strip detectors: less material in particle path, larger size per device, lower cost, and, in principle, much longer lifetime. Both of these devices are being built and tested by the LBL gas microstrip detector group. Goals of the group are to compare the two types of devices, and improve their designs so as to maximize their performance with respect to gain, lifetime, size, resolution, and cost.
It is expected that one outcome of this development will be applications in new experiments.
Potential application of the same principles toward new types of detectors is also currently under investigation.