Hit Density Rates for MVD
Wieman 5/08/04
revised 5/13/04
revised 5/15/04
To estimate the number of pileup tracks
Note: dN/dz is written
as dNdz this is true for all derivatives in this analysis.
This simplifies to: (see space charge analysis code)
pseudo rapidity particle density for central
Measured min bias cross section at RHIC, F. Retiere
Minbias event rate, ZDC count rate
9.1 kHz at the start of a good run, see Run Log entry for run 5081011
03:21 21-March-2004, this must be at the time that the run has been started. This run peaks at 12 kHz according to the RICH scalers. There is another run that peaks higher at 15 kHz (phone call to Marco Van Leeuwen who checked RICH scalers. We will use 10 kHz as the nominal maximum rate because there will always be a start up delay. Improvements in luminosity are expected largely to be improvements in average, but RHIC II will have peak luminosity increases of 2-3 times the 15 kHz reported above.
Min bias cross section for ZDC coinc. (Jamie Dunlop)
The canonical design luminosity is 2X1026/cm2/sec for Au+Au, so this is 5 times design.
Does the integral look right? We expect 2 for the integral over ~-1<h<1
Find z at h = 1
guess value
found value
OK checks out
Convolute the dh/dz distribution over the diamond
OK looks all right
central
min bias
One event hit density for silicon with central event
Hit density for a central event on the outer surface of the MVD
Hit density for a central event on the inner surface of the MVD
Hit density rate for Au Au interactions at the maximum luminosity at a given radius.
Hit density rate on the outer MVD outer barrel
Hit density rate on the inner MVD outer barrel
Hit density with 4 ms frame read time MVD outer barrel
Hit density with 4 ms frame read time, MVD inner barrel
Probability of a cell of area DA having signal from more than one hit
Assume that 9 pixels get a signal from each hit
Pixel area
Pixel pileup probability for central collision
MVD outer barrel
MVD inner barrel
Pixel pileup probability for 4 ms integration, L = 10^27 Hz/cm^2
MVD outer barrel
MVD inner barrel
Probability of more than one hit in the tracking search window projected from SVT to MVD outer barrel.
Projection uncertainly from the SVT to the MVD outer barrel for 1.2 GeV/c pion, determined with GEANT tracking simulation, F. Retiere
To get 98% hit acceptance the search window should have a radius of 2.8 s, see
AcceptanceWindow.mcd
Area of the tracking window using 2.8 s radius
search window pileup probability for central collision
at MVD outer barrel
Search window pileup probability for 4 ms integration, L = 10^27 Hz/cm^2
at MVD outer barrel
Probability of more than one hit in the tracking search window projected from MVD outer layer to MVD inner layer.
Projection uncertainly from MVD outer layer to inner layer 1.2 GeV/c pion, determined with GEANT tracking simulation, F. Retiere
To get 98% hit acceptance the search window should have a radius of 2.8 s, see
AcceptanceWindow.mcd
Area of the tracking window using 2.8 s radius
search window pileup probability for central collision
at MVD inner barrel
Search window pileup probability for 4 ms integration, L = 10^27 Hz/cm^2
at MVD inner barrel
Proabability for in correctly associating a bacground hit with the track
projection numbers for 1 GeV/c pions from Fabrice Excell spread sheet, May 21,04
mis hit probability formula, see
GhostTracks.mcd
Probability for background hit assignment error
MVD outer, integrated background
MVD inner, integrated background
MVD outer, central collision Au+Au
MVD inner, central collision Au+Au