Position resolution of a high efficiency transition radiation detector for high counting rate environments

A comprehensive study of rate capability in Multi-Wire Proportional Chambers

“…Being the gap dependence so critical for MWPCs in terms of photo-absorption probability, it is worth discussing the possibility of using a drift region (of length D). For typical pad sizes of 1 cm 2 [7], the maximum CBM fluxes would imply a particle load of 1/10 µs per channel causing a 10% pile-up probability within 1 µs. Taking the measured drift times in [4], even in a small drift region corresponding to D = 2h, the electron drift would extend up to a typical time of that order [4], making accurate charge measurements very difficult.…”

“…On the basis of the above arguments, staying at a MWPC configuration seems to be the most convenient solution for the CBM TR-detector. The possibility of using a mirrored configuration [7] with 3 cathode planes deserve further consideration, since it increases the X-ray detection probability while keeping the rate capability. If this improvement is worth the extra mechanical complexity or not will be clarified when the first real size prototypes are built.…”

“…In particular, a new generation of fast MWPC counters aimed at TR detection has been envisaged for the CBM experiment at FAIR [5]. The system's conceptual design (presented in [6]) is based on a configuration aiming at a pion suppression better than 100 for momenta higher than p=1.5 GeV/c with position resolution of the order of 200-300 µm [7] at incident fluxes up to φ = 100 kHz/cm 2 . These requirements are driven by the identification of J/Ψ and Ψ ′ in the di-electron decay channel.…”