PHENIX EMCal meetings -- recent transparencies

EMCal Group meeting, October 2, 1997

How timing is simulated in PISA ( Gabor David )
Description of the algorithm
Measured PMT pulseshape reconstructed from an oscilloscope photograph (electrons). 0-100 risetime is about 4.5 ns, FWHM is about 9 ns.
PMT pulseshape in PISA simulated for 0.30 and 0.35 GeV electrons (shifted horizontally). 0-100 risetime is about 5 ns, FWHM is about 8 ns.
Light and PMT pulse (1) The blue histogram represents the light as presented to the PMT (horizontal scale in ns, vertical is equivalent GeV). The red histogram is the fully reconstructed PMT pulseshape. (Input: 1 GeV electrons)
Light and PMT pulse (2) The blue histogram represents the light as presented to the PMT (horizontal scale in ns, vertical is equivalent GeV). The red histogram is the partially reconstructed PMT pulseshape. (Input: 5 GeV pions.) To speed up the code, reconstruction of each partial pulse is stopped once the sum of this as and previous partial pulses crosses the leading edge threshold. Note that the pulseheight is normalized to the corresponding energy (see the late, small pulse on the top panel).
Slewing curve (1) derived from 10 GeV photon showers (0.1 GeV lower cut on tower energy). The penetration is deep, the apparent absolute time is slightly earlier than for the 1 GeV showers below.
Slewing curve (2) derived from 1 GeV photon showers (0.1 GeV lower cut on tower energy). The average penetration is less than before, the apparent absolute times are later, than before.