Ignore the "KEK November 2007" title - that's a legacy and is already changed :-)
As of now, there is no distinction in 16 separate zones. However, the gaps between the the zones are clearly visible in the Hit Profile, as the edge strips on both sides have a larger sensitive area and thus collect more hits than other strips; hence the spikes in the (otherwise pretty gaussian) beam profile. There is a single strip with no entries in the center - that's the one that suffered from the bias bond repair action.
SNR=21 (peak mode) is pretty healthy and fits to similar detectors operated with APV25.
All data was taken in multi-peak mode with subsequent hit fitting to obtain amplitude and timing (see separate posting for timing precision).
The verbose output of the analysis is pasted below.
Analysis of vie_run001
Peak Mode, 3 x 200 initevents (first 10 skipped) + 99400 events
Number hybrids: 1 number zones: 2 number sensors: 1
Using calibration file vie_cal001
No pedestal correction file
Seed/Neighbor/Cluster/Noisy Strips Cuts [RMS noise]: 5.0/3.0/5.0
Min. hitlength: 3
Comments:
SILC module 01
HV=100V, 40MHz, Tp=50ns, 30ns
Sr90 1mCi , black cloth cover
Analysis date: 23.04.2008 13:25:09
Analysis settings:
runname: vie_run001_cluster
clock: 40.00 MHz
datafilepath: data/
outputpath: output/
subevents: 6
fitmode: 2 (cal. fit)
options: h
Results:
ModuleName ZoneType Ch OKCh OK% Entries MClW MPSignal Noise MPSNR HpSE Occup
p_side JP single sensor 256 256 100.0 90385 2.53 21546.1 729.4 20.68 0.53 1.81 |
soeben haben wir den micron-DSSD (double metal layer) in den 2-teiligen rahmen geklebt und auf beiden seiten
temporäre kapton-stückerln aufgeklebt, über die bias appliziert werden kann. nach trocknung und bonden der
bias-verbindungen (montag, 5.5.2008) wird dieser für sensor-tests zur verfügung stehen. |
*** NOTE: AFTER THIS MEASUREMENT WE REALIZED THAT BIASING WAS NOT DONE PROPERLY
HENCE THE RESULTS BELOW ARE NOT RELIABLE
(in fact it is surprising that they are not worse) ***
Please find the results of the lab source test on the new Micron module here.
It is read out with 3 + 3 APV chips on either side.
Results table of the source measurement:
p-side n-side
Cluster signal [e] 18361 19434
Strip noise [e] 1142 1193
Avg cluster width 1.91 1.30
Single strip SNR 16.1 16.3
Cluster SNR 11.6 14.3
Strip pitch [um] 50.0 153.5
Apparently, the double metal capacitance is not so bad as expected, even though the Micron sensor does not use
the hourglass crossing scheme. Presumably the dielectric between metal 1 and 2 is rather thick (several um).
Strip noise is roughly the same on both p and n side, so the difference in Cluster SNR (*) only stems from the
unequal cluster width (which is a result of the different pitches).
Peak time precision vs SNR (last plot below) is worse compared to the values obtained with various HPK sensors
in the November 2007 beam test at KEK. However, this is a comparison of source and beam and thus might not be
significant. Let's see what we will get in the SPS beam test next week.
(*) Cluster SNR := sum(signal) / (strip_noise * sqrt(cluster_width) ) |