1. Instrumentation Division Seminar

    Presented by Harry van der Graaf, National Instutute for Subatomic Physics, Netherlands

    Monday, April 14, 2014, 2:30 pm
    Large Conference Room, Bldg. 535

    We propose to place a stack of ultra thin transmission dynodes on top of a pixel chip, in vacuum. A single electron arriving at the first dynode will cause an electron avalanche on the pixel input pad. Due to the small source capacitance, a gain of 30 k of the dynode stack is sufficient to create a digital signal. The rise time of this signal could be ~ 2 ps. This single-electron sensitive device has therefore an excellent time resolution, and, due to the granularity of the pixel chip, a good 2D position resolution. When capped with a classical window + photocathode, a new photomultiplier is created. This Timed Photon Counter 'Tipsy' is single soft photon sensitive, has 2D position resolution defined by the granularity of the pixel chip, and a potential time resolution of ~ 2 ps per photon. Thanks to the granularity of the pixel chip, a high rate of multiple photon events results in an acceptable pixel occupancy. When capped with an electron emission membrane 'e-brane', the electron detector turns into Trixy: a tracker for charged particles (MIPs). The essential property of this membrane is the emission, with a high probability, of at least one electron after the passage of a MIP, at the crossing point of the MIPs' track and the membrane. We report on the progress in the development of the transmission dynode, and on theoretical aspects and simulations associated with the emission of (secondary) electrons.