Energy loss measurement in a MWPC

Abstract

Experimental results on the influence of angle and cell geometry on pulse height measurements in a multiwire proportional chamber (MWPC) are presented. Two track orientations are mainly considered: (a) tracks parallel to the wire plane and (b) tracks traversing the gap with one wire touched. In case (a), the positive induced pulse effect is analyzed: pulse heights have to be corrected by factors of 1.3-1.7 and wire inefficiency can be found up to 20%, depending on the cell geometry. The saturation effect starts earlier in case (a), but the influence of the angle between track and wire when approaching 90 ° is moderate. On the contrary, this influence is very effective in case (b). A detailed study of this phenomenon is then presented with a description of possible mechanisms involved.

Relativistic Charged Particle Identification by Energy Loss

“…This depends on the bandwidth of the electronics, the electronic noise, the number of ionization electrons, and the gas amplification factor (Pleming 1977). The gas amplification cannot be increased beyond about 104 without the risk of angle-dependent saturation effects (Frehse et al 1978, Allison et al 1978c. More significantly, for long drift-path geometries the production of positive ions in the gas amplification produces a volume space charge that distorts the drift field (Allison et al 1974, Friedrich et al 1979.…”

Control of laser machining of polycrystalline diamond plates by the method of low-coherence optical interferometry

“…If the second cluster arrives somewhat shifted sideways along the wire, which occurs for inclined tracks (0 f 0), the reduction in gas gain will be less severe. Figure 16 shows a set of measurements for variable 8 and different gas amplification factors [25]. The diffusion makes this effect also sensitive to the drift distance x since the spread of the ionization along the wire reduces the local space charge at the wire.…”

Techniques and Concepts of High-Energy Physics II

“…The effect is particularly relevant when particles traverse the detector at different angles: Figure 32 (Frehse, Lapique, Panter and Piuz, 1978) shows the variation in normalized detected charge as a function of gain for various angles of incidence (0 0 means a track perpendicular to the anode wire). At gains around 10 4 the variation is already 30% Figure 32 between tracks at 0° and 45°.…”