Left-right resolution in high magnetic fields for the CHAOS inner drift chamber

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 325; no. 3; pp. 384 - 392
• Main Authors: Hofman, G.J., Brack, J.T., Amaudruz, P.A., Smith, G.R.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.02.1993
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/0168-9002(93)90384-T

Design considerations for a pion spectrometer being built at TRIUMF led to the development of a thin, low mass, single plane cylindrical drift chamber with a simple cell structure consisting of alternating anode and cathode wires. To date no solution to the left-right ambiguity in chambers of this type has been found which works in high magnetic field environments and for arbitrary incident track angles. We hypothesized that the left-right ambiguity could be resolved in a chamber of this type by comparing the induced charge on cathode strips which are parallel to the sense wire and located in diagonally opposed corners of the cell. Measurements with prototype chambers in magnetic fields up to 1.6 T show that the left-right ambiguity is indeed resolved well for tracks with incident angles between −45° to +45°. The measured intrinsic chamber resolution for tracks at normal incidence at B = 1 T is 150 μm ( σ).