Transcript gastof8 - Indico

Gas sTOF, or gastof
Luc Bonnet, Tomek Pierzchała, Krzysztof Piotrzkowski, Pierre Rodeghiero
Université Catholique de Louvain
• Status:
– prototypes
– tests
• Next steps and plans
New developments
• Plan to use fastest PMTs on the market:
They are very expensive, ~ 20k euro apiece… but
within a small collaboration with HPK we received
two such MCP-PMTs (with HPK amplifiers) for tests.
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
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Irradiation tests
• Hamamatsu is interested in testing
radiation hardness, so we will characterize
PMTs before and after neutron irradiation at
Louvain – first irradiations planned for
mid-November, next around January
• For PMTs we will start with low doses at
1010-11 n/cm2 level, and gradually increase it
– URGENTLY needs input from simulations on
doses around pockets; for detectors (mirrors)
assume Hector estimates (1014-15 n/cm2)
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
3
Irradiation tests cont’d
• Will keep PMTs at HV during irradiation
(~24h), and will couple to Sci bars so pulse
shape (rate?) will be monitored on-line (and
registered)
• For precise characterization before/after
irradiation need a dedicated setup 
• We should use this opportunity to tests
other components – we will irradiate UV
mirrors, and measure their reflectivity
before/after; what about Burle and quartz
bars??
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
4
Laser stand
• Borrowed picosecond laser driver (PiLas)
and bought UV laser head PIL040 - 408 nm,
32 ps pulse FWHM and < 3 ps jitter!
EIG1000D with PIL063SM (fiber coupler and fiber)
• PiLas Digital Control Unit
(EIG1000D)
• Optical Heads (PILxxx) for
375 nm – 1550 nm)
Crucial also for design and development of
electronics as amplifiers, CFDs and DAQ! Good
for simulating LHC high event rates – runs up to
1 MHz repetition rate.
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
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gastof
prototyping
The prototype
of GASTOF
High Voltage < 2600V
output of Burle
64 or 16 combined anodes
combined
mirror and Bur
efficiencies
C4F10
1.2 bar, n~1.0018
7 TeV
protons
45deg
Cone of Cerenkov photons
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
6
Laser pulse is large (~108 photons)- needs
strong attenuation and monitoring/calibration:
• PIN photodiode
monitoring is
running:
• In assembling - optical box allowing for
setting intensity of photon pulse in large
range, for example N = 0.1-1000 photons
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
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Variable and fixed
filters
PiLas UV head
PMT or
photodiode
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
8
We work on new Gastof prototypes with Hamamatsu
PMTs – we need for that different optics - in
contact with producer of spherical mirror to
focus Cerenkov light on 11 mm  photocathodes
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
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10 cm spherical mirror
Best optical configuration still under study;
For mechanical design – decision on insulation
vacuum is crucial ( thin window design)
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
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Electronics:
• Continue building fast amplifiers, but
main challenge now is design of CFDs – first
prototype in production; started to design a
NIM multi-channel board with possibility of
remote control (directly from LabView using
RS232)
• Managed to run a CERN HPTDC VME module in
the standard mode, will try squeezing out
ultimate performance (with PiLas?)
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
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Next Fermilab tests:
• Revamp two old Gastofs with 10 mm Burle
tubes and new mirrors; will use also single
anode readout
• Produce new two prototypes with Hamamatsu
PMTs and spherical mirrors (+ reflective
detector walls)
• New electronics
• …
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
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Further Plans:
• Continue prototyping (also with Burle
10mm) and studies of Gastof designs to cope
with multi-proton events:
- very fast Gastof with 1 or 2 single
anode Hamamatsu MCP-PMT
- fast Gastof with Burle multi-anode tubes
but single anode readout
- possible FP420 configuration – one of
each?
• High resolution DAQ – will contact SPC-134
system producers (< 5 ps resolution) to
evaluate possible use for FP420
• Study ways beyond 10 ps regime…
K. Piotrzkowski, UCLouvain
FP420@CERN, November'06
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