1. The Electromagnetic Calorimetry of the PANDA Detector at FAIR
R.Novotny
II.Physics Institute, University Giessen, Germany
and for the PANDA collaboration
the overall concept
the target spectrometer
the PWO-II crystals
read-out concept
performance
the forward spectrometer
the design concept
performance down to low energies
summary and outlook
July 8, 2012
CALOR R.W.Novotny

2. Facility for Antiproton and Ion Research
Primary beams: SIS100/300
p: ·1013/s up to 29 GeV
U28+: 1012/s up to 2.7 GeV/u
U92+: 1010/s up to 35 GeV/u
Secondary beams
RIBs up to 2 GeV/u
Antiprotons up to 15 GeV
Storage and cooler rings
Facility for Antiproton and Ion Research
Darmstadt, Germany
Nuclear structure
& astrophysics
Nuclear matter
physics
Hadron
Plasma
Atomic
July 8, 2012
CALOR R.W.Novotny

3. the PANDA detector at FAIR
Target Spectrometer
4p detector for spectroscopy and reaction dynamics with antiprotons
barrel
~11.000
endcaps
~4.000 crystals
PWO-II
200mm (23Xo)
photon detection with high resolution
over a large dynamic range:
10MeV < Eg < 15GeV
high count-rate capability (2∙107 Annihilations/s)
nearly 4p coverage
sufficient radiation hardness
timing information for trigger-less DAQ concept
shashlyk-type
Sampling Calorimeter
July 8, 2012
CALOR R.W.Novotny

4. the Target Spectrometer: based on high-quality PWO-II
July 8, 2012
CALOR R.W.Novotny

5. quality control and performance
July 8, 2012
CALOR R.W.Novotny

6. optical transmission light yield @RT radiation hardness July 8, 2012
CALOR R.W.Novotny

7. overall quality:
July 8, 2012
CALOR R.W.Novotny

8. the Target Spectrometer: Barrel
16 slices
pointing off-target
crystals
200mm long (22Xo)
2 x 11 tapered shapes
July 8, 2012
CALOR R.W.Novotny

9. the Target Spectrometer: Forward Endcap
comprising
3864 crystals
July 8, 2012
CALOR R.W.Novotny

10. photosensors: Large Area Avalanche Photo Diodes (LAAPD) CMS 5x5mm2
in collaboration with Hamamatsu Photonics
CMS
5x5mm2
10x10mm2
new
excellent performance
at RT and T = –25oC
radiation resistent
up to 1013 protons
in particular at T = -25oC
final concept: LAAPDs/crystal,
separately readout
dimensions
7 x 14 mm2
July 8, 2012
CALOR R.W.Novotny

11. vacuum photo triodes / tetrodes VPT
photosensors:
vacuum photo triodes / tetrodes VPT
to adapt to higher countrates (>500kHz) in forward direction
faster response – better timing options
under development
RIE St. Petersburg, Russia
Tetrode (photo cathode, 2 dynodes, anode)
G = 24 – 45
QE = 14 – 20%
July 8, 2012
CALOR R.W.Novotny

12. development of low noise, low power preamplifiers
design of descrete components
for prototype studies
18mm
ASIC (APFEL) large dynamic range
2 channels/ 2 ranges
overall range 1 –
noise level (cooled)
<< 2 MeV
July 8, 2012
CALOR R.W.Novotny

13. prototype performance
optimized light output: PWO-II
cooling: operation at T=-25oC
prototype performance
response to high energy photons
64 MeV < Eg 1.5 GeV
g‘s e-
tagged photon
facility
@ MAMI, Mainz
extension to energies < MaxLab
readout with
photomultiplier
Eg=43.3MeV
Eg= 26 MeV
readout with
photomultiplier
July 8, 2012
CALOR R.W.Novotny

14. prototype performance PROTO 60
photon beam
crystals in PANDA geometry
readout with single LAAPD only
quad preamplifier
LED based monitoring system
temperature stabilization <0.05oC
July 8, 2012
CALOR R.W.Novotny

15. prototype performance PROTO 60
counts
incident photon energy / MeV
deposited energy / MeV
158 MeV
858 MeV
1.44 GeV
s / E / %
digitization:
shaping /peak-sensing ADC
July 8, 2012
CALOR R.W.Novotny

16. readout via SADC: further improvement
energy-resolution
( 3x3 matrix )
time resolution
1 ns
July 8, 2012
CALOR R.W.Novotny

17. prototype performance PROTO 60 15 GeV positrons
s/E= 1.4%
s(x,y)~1mm
July 8, 2012
CALOR R.W.Novotny

18. consequences of cooling:
fast decay kinetics even at T=-25oC
LY(100ns)/LY(1µs) > 0.9
constant ratio
LY(-25oC)/LY(+18oC) = 3.9
„no“ recovery of radiation damage at T=-25oC
asymptotic light loss correlated with Dk (RT)
T= -25°C
RT / m-1
rel. light 25oC / %
July 8, 2012
CALOR R.W.Novotny

19. recovery of radiation damage @RT
@T= -25oC
applied integral dose of 60Co: D = 30Gy
July 8, 2012
CALOR R.W.Novotny 19 19

20. implications for EMC operation
July 8, 2012
CALOR R.W.Novotny

21. 1 supermodule = 4 submodules
forward EMC Pb S
lateral dimensions of one supermodule:
(110 x 110) mm²
scintillator thickness: mm
lead absorber thickness: mm
number of absorber layers:
number of WLS fibers:
total weight: kg
eff. radiation – length: X0 = 34.9 mm
eff. Molier – radius: ρM = 59.8 mm
Shashlyk module:
1 supermodule = 4 submodules
- scintillator tiles
- readout of fibers with PMTs
July 8, 2012
CALOR R.W.Novotny

22. forward EMC
July 8, 2012
CALOR R.W.Novotny

23. forward EMC test @ A2-MAMI tagged photons July 8, 2012
CALOR R.W.Novotny

24. forward EMC but! reconstructed amplitude depends on position
+ time resolution:
~ 100ps/SQRT(E)
+ position resolution:
~ 1 cm
longitudinal nonlinearity
July 8, 2012
CALOR R.W.Novotny

25. forward EMC test @ Protvino electrons July 8, 2012
CALOR R.W.Novotny

26. many thanks for your attention ….
conclusion
and outlook:
many thanks for your attention ….
final construction will start in 2013 …
to be ready in 2017
completion of scintillators major uncertainty
July 8, 2012
CALOR R.W.Novotny