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Next: DESCRIPTION OF MGWC's
Up: FIRST RESULTS ALREADY PUBLISHED
Previous: FIRST RESULTS ALREADY PUBLISHED
Multiwire proportional chambers (MWPC) [1] have extensively been used in high energy experiments during the last 27 years. These chambers are mainly involved in charged track reconstruction but also, due to their high gain, to detect single electrons in RICH detectors [2, 3]. Many studies have been performed using different geometrical configurations, electrostatic conditions and gasses. Limitations and ageing problems have thus well been studied and understood [4].
The microstrip gas chambers
(MSGC) [5] have been proposed
for high rate experiments to provide higher spatial
resolution and speed.
These detectors, having anode and cathode strips printed alternatively
on a flat substrate using semiconductor technics, are easily
constructed.
Nevertheless, they have two main disadvantages: their gain does not exceed
104 and the charge accumulation on the substrate (due to the positive
ions created during the multiplication process)
induces operation instabilities.
The micro-gap chambers (MGC) [6] have been
proposed to solve these problems.
The cathode and anode planes are separated by thin dielectric strips.
The substrate being completely covered by the cathode is not any more
charged by the positive ions as in MSGC's.
Furthermore, due to the presence of the electric insulator between the anodes and
cathodes, the gains obtained ( 
10
4
) exceed those of the MSGC's.
The fact that the printed anodes are flat in MGC's produces a big variation on the electric field between their two edges and the middle, thus inducing big gain variations depending on the avalanche position.
In the present paper we describe a detector having a geometry similar to the MGC's where the printed anodes are replaced by wires. These chambers, called Micro-Gap Wire Chambers (MGWC), combine the high gain and stability of the MWPC's with the high resolution of the MGC's.
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Marcos Dracos Sat Apr 4 18:31:19 METDST 1998 | 
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