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Jens Frangenheim [email protected] III. Physikalisches Institut A RWTH Aachen University. CMS Upgrade Workshop at FNAL, 2008/11/19 to 2008/11/21 Muon Detector Working Group, Thursday, 2008/11/20 09:40. Specific interests of German groups. Hardware development - PowerPoint PPT Presentation
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Specific interests of German groups
General detector development plans
Aachen IIIA / IIIB and DESY collaboration
Associated work
First steps
Jens [email protected]. Physikalisches Institut ARWTH Aachen University
CMS Upgrade Workshop at FNAL, 2008/11/19 to 2008/11/21Muon Detector Working Group, Thursday, 2008/11/20 09:40
Hardware development for a scintillator based MTT
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Muon fast Track Tag
muon tag
muon system+ absorption by calorimeter and coil - tracks affected by multiple scattering + redundancy given by RPCs
tracker- huge number of tracks+ precise p
t measurement
(high resolution, less material, strong B-field)
calorimeter
tracker
idea: Bologna
one option: use scintillator based MTT
by A. M
ontanari
also Aachen III, DESY
use a new part of muon system (MTT) to select an interesting region in the
tracker in L1-trigger
general detector development plans
in addition to Bologna
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MTT design – German focus
based on the MTT idea including dimensions developscintillator detector
German groups focusing on detector development and building(long tradition in Aachen)
general detector development plans
(slide 18 from Pierluigi`s talk)
CM
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09
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MTT hardware – dedicated technologyIdea: Scintillator based MTT readout by SiliconPhotoMultipliers
maintenance free no gas needed very fast any requested resolution
possible
no HV needed (Usupply
< 100 V) less power needed (< 0.2 mW/mm2) very good timing (100 ps to 1 ns) high photon detection efficiency (up to 65 %) but high noise rate (up to 1 MHz/mm2 at 0.5 PE threshold) and small active surface (up to 3 mm x 3mm at the moment)
Hamamatsu SiPM: 100 µm x 100 µm pixels
Best suited device for triggering at the moment:- highest photon detection efficiency - low noise - will soon be produced in CMOS technology (cheap)
general detector development plans
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Aachen IIIA / IIIB and DESY collaboration
Aachen IIIA: - simulations about light collection /SiPM signal timing - combining MTT with muon chamber Aachen IIIB: - experience from tracker development - SiPM supply electronics development
Aachen IIIA + Aachen IIIB: (finally) building the MTT
DESY: HCAL group member, possible integration with HO
Aachen IIIA / IIIB and DESY collaboration
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MTT at Aachen IIIA – Scintillator designsTwo possible designs:
“Traditional” one:scintillator plates with embedded WaveLengthShifting fibers
+ light collecting in WLS fiber → more light/photon detector surface - mechanical efforto good time resolution
“New” one:SiPMs directly mounted to scintillator plates (was done with huge PMs)
o low light yield - but readout perhaps possible (high pde, large SiPMs (~ price as smaller ones)+ simple mechanical construction+ very good time resolution- maybe more readout channels, power consumption
scintillator (blue light)WLS fiber(green light)
photon detectors
Aachen
Aachen IIIA / IIIB and DESY collaboration
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diffuse reflection
“normal” reflection
total reflection
MTT at Aachen IIIA – Light collection studies
Aachen IIIA / IIIB and DESY collaboration
Aachen IIIA cosmics testing (student project)
- try to find best position of SiPMs, wrapping of scintillator, shape of WLS fiber
- have developed “standalone“ scintillator + SiPM simulation
- diploma student is working on GEANT simulation
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MTT at Aachen IIIBAachen IIIB brings in experience from tracker (petals) assembling / testing:
- one focus: development of compact SiPM readout electronics
- especially: development of a gain stabilization on a chip (SiPM gain is temperature and maybe time and radiation dose dependent)
Aachen IIIB SiPM-cosmics testing
Aachen IIIA / IIIB and DESY collaboration
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timing (kind of coincidence, time resolution)
(trigger) electronics tests
build large test detectors
tests together with other detectors (muon chamber, petal)
MTT test detector
muon chamber
tracker petal
cosmic m
uon
cosmic m
uon
MTT at Aachen – common Aachen IIIA/B parts
CMS silicon petal quality control at Aachen IIlB
Aachen IIIA / IIIB and DESY collaboration
SiPM mounted on Aachen pcb, first test with scintillator
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MTT at DESY
Aachen IIIA / IIIB and DESY collaboration
- DESY member of HCAL group (CASTOR)
- interested in combination MTT with HO
- change of HPD in SiPM for HO needed → exchange of initial two readout-boxes planned for this shut down → get experience with the longterm operation with SiPM (new detector technology, also at T2K starting 2009)
- further discussion between Muon and HCAL groups underway, need experiences with HO with SiPMs and for sure simulations everywhere
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Associated work
associated work
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Implementation of MTT into CMSSW
scintillator can probably not distinguish between kinds of particles
scintillator does not measure momenta
MIP produce less light than background (e.g. slow protons, electrons)
background rate of all (charged) particles including low momentum particles
timing of background (and signal)
momentum of background particles (absorbing / producing secondary particles)
Scintillator very sensitive to background !
associated work
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Absorber (thin, between 2 scintillator layers):Absorbs low momentum particles between the two layers.→ MTT gets too thick ? Two layers too expensive ?
Use multiple scattering/magnetic field deflection → Does not work with one MTT element.
Set time-of-flight gate:Reduce sensitivity to neutron background, slow pions and kaons → Need high time resolution, more electronics ?
Set pulse height amplitude (=amount of light) limit:(background produces mostly more light than MIPs)
Combination with HO
Strategies to limit sensitivity of MTT to background
associated work
MTT layer 1
MTT layer 2absorber (Pb)
slow e-
neutron induced proton
pion
new particles
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First steps
first steps
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Simplest scintillator based detector
100 mm
SiPMs (3 mm x 3 mm) in unconventional position
idea
: T.H
. for
SL
HC
+ very simple set up
+ thin construction
+ very good time resolution
- a lot of SiPMs needed
- many readout channels (but high resolution)
SiPMs directly coupled to front side of a piece of scintillator
Aachen
first steps
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Simulation results (2)
first steps
4 PE threshold
Assuming: - 90 % diffuse reflexion at surrounding 3M tape - 3 mm x 3mm detectors - 65 % photon detection efficiency (80 % coupling efficiency)
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Simulation results (2)
efficiency > 80 % for 10 mm thick scintillators
(gets ~ 100 % for 95 % reflective wrapping)
(to be tested with larger scintillators)
first steps
need 2 of 4 coincidence(4 PET for each SiPM)
noise rate < 1 Hz
no correlation with no correlation with SiPM position visibleSiPM position visible
position of SiPM
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Simulation for WLS fiber setup (1)
first steps WLS fiber simulation
100
100
10
piece of scintillator (BC-404)
WLS fiber (BCF-92)
SiPMs (Hamamatsu 100 pixels, 1 mm x 1 mm)
- uniform distributed, vertical particle transition- require coincidence (interval < 10 ns) between both SiPMs with 3 PET→ noise rate < 1 Hz
)
simulated 10000 muons traverses
µ
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first steps
Simulation for WLS fiber setup (2)
light collection effect of WLS fiber huge
more than 98 % detection efficiency (using 1 mm x 1 mm SiPMs)
time resolution of detector still good
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Conclusion MTT is a promising concept to include tracker data into L1 muon trigger: - DT and RPC can be kept as independent systems. - MTT can also solve DT occupancy problem (at L1-trigger).
Scintillator based MTT could be an easy and cheap solution: - It can be inserted in addition to existing detectors. - SiPMs are a very promising technology. - German groups can contribute to detector development and building. - MTT/HO: under discussion, several aspects to be clarified
At SLHC may need any kind of redundancy !
conclusion