Small FDIRC designs

Abstract

In this article11The paper was presented at the RICH 2016 conference, Bled, Slovenia, September 2016. we explore the angular resolution limits attainable in small FDIRC designs taking advantage of the new highly pixelated detectors that are now available. Since the basic FDIRC design concept attains its particle separation performance mostly in the angular domain as measured by two-dimensional pixels, this paper relies primarily on a pixel-based analysis, with additional chromatic corrections using the time domain, requiring single photon timing resolution at a level of 100–200ps only. This approach differs from other modern DIRC design concepts such as TOP or TORCH detectors,22See presentation at this conference. whose separation performances rely more strongly on time-dependent analyses. We find excellent single photon resolution with a geometry where individual bars are coupled to a single plate, which is coupled in turn to a cylindrical lens focusing camera.