Thebackground of CALIFA CsI(Tl) elements
for detailed description of CALIFA elements, see CWG video report Feb 26,2008 by V. Avdeichikov
Crystals produced by Amcrys Ltd., Khar’kov (Ukraine)
CALIFA - 90º elements
10x30x130x15x42 mm**3
Forward Cap elements??
20x20x210x26x26 mm**3
Calorimeters for HEP. Amcrys Ltd production
MeV100@%8.2E
MeV400@%9.1E
CsI(Tl)
BELLE (KEK) barrel 4640 pcs. 22.52 tonsendcap 1506 pcs. 7.87 tons
BaBar (SLAC) barrel 1643 pcs. 6.281tonsendcap 216 pcs. 0.78 tons
device crystal modules103
depthX0
photosensor BT
where beam energy
GeV
Belle CsI(Tl) 8.8 16 Si PD 1 KEK 8+3.5
BaBar CsI(Tl) 6.8 16 Si PD 1 SLAC 9+3.1
M.Moszynski CsI(Tl)/0.8 cm**3
Our data
CsI(Tl)/APD (10x10), Energy resolution for rays. Batch of 8 CsI.
( <M>=50, ALICE Preamp., shaping time = 2 s)
12 CsI(Tl) Khar’kov samples
<M>=100
V.Avdeichikov, NUSTAR meeting GSI Jan-08
C sI (T l )/A P D (10x10)< M > = 50
0. 569
0. 660 1. 063 M eV
1. 33
2. 50
C ol lected L ight, channels
C sI (T l )
A P D
Ene
rgy
Res
olut
ion,
%
l = 130 mm10x3
0 15x4
2
10x1
0
1
2
3
4
5
6
7
89
10
600 800 1000 2000 3000 5000
CsI(Tl)/APD in
CALIFA-4 samples
1. Whole CsI(Tl) volume is irradiated. LO non-uniformity for tested crystals have been modified to 0.15 – 0.28%
2. Original LO inside one batch energy resolution 10% - 15%
3. 44-51% of Light is collected by the lightguide
4. We are close to the limit in R%
(Solid lines is driven to guide an eye)
(Shaping time – 2 s)
sL ight O utput, channels
T _ protons = 180. 0 M eV
K har ' kovSt. G obain
P ulser , = 4. 3 channels
Energy Resolu
tion, %
0
0. 2
0. 4
0. 6
0. 8
1
0 500 1000 1500 2000 2500 3000 3500 4000
Protons
Gammas
K har ' kov
St. G obain
L ight O utput, channels
Ene
rgy
Res
olut
ion,
% T _ proton = 180 M eV
0
0. 2
0. 4
0. 6
0. 8
1
0 500 1000 1500 2000 2500 3000 3500 4000
0.4%
0.6%
CWG meeting April 08
C sI (T l )/A P D (10x10)< M > = 50
0. 569
0. 660 1. 063 M eV
1. 33
2. 50
C ol lected L ight, channels
C sI (T l )
A P D
Ene
rgy
Res
olut
ion,
%
l = 130 mm10x3
0 15x4
2
10x1
0
1
2
3
4
5
6
7
89
10
600 800 1000 2000 3000 5000
Extra long, 210 mm, CsI(Tl) crystals
20x20x210x26x26 mm**3
Option forForward Cap?? for the EXL setup??
20x20
26x26
10x10
L=210 mm, V=110 cm^3
Some preliminary test results…..
Collected Light, channels
Ener
gy R
esol
utio
n, %
CsI(Tl)/APD(10x10)
<M> = 50
0.5690.660
1.063 MeV
1.33
2.50
APD
CsI(Tl)
l = 210 mm20x2
0 26x 2
6 10x 1
0
1
2
3
4
5
6
7
89
10
600 8001000 2000 300040005000
C sI (T l )/A P D (10x10)< M > = 50
0. 569
0. 660 1. 063 M eV
1. 33
2. 50
C ol lected L ight, channels
C sI (T l )
A P D
Ene
rgy
Res
olut
ion,
%
l = 130 mm10x3
0 15x4
2
10x1
0
1
2
3
4
5
6
7
89
10
600 800 1000 2000 3000 5000
Energy resolution of 130 mm CsI(Tl)/APD elements for -rays. 12 elements measured
LO uniformity = (0.30 – 0.70)%
Energy resolution of 210 mm CsI(Tl)/APD elements for -rays. 3 elements measured.
LO uniformity = (0.5-1.0)%
C hannels
Shielded by A l , 1mm , box
Shielded by P b, 40mm, boxN (> 50 keV ) = 65 1/ sec
N (> 50 keV ) = 170 1/ sec
C sI (T l ) element, 55 cm3
(1. 461 M eV - K 40)
1
10
10 2
10 3
0 500 1000 1500 2000 2500 3000 3500 4000
C hannels
C sI (T l ) element, 55 cm3
C sI (T l )/A P D
C sI (T l )/ P M T
50 keV
N (> 50 keV ) = 170 1/ sec
P ulser , 8. 7 keV - F W H M
x2
1
10
10 2
10 3
0 200 400 600 800 1000
background counting rate for CALIFA-5 element with E> 50 keV
Noise tail??
Al, 1 mm
Pb, 40 mm
Threshold will depend on light collection. For Califa CsI/APD(10x10) the Light Collection is around 44-51%. Spectroscopic threshold, in average, 25 keV(see next slide)
For Califa CsI/PMT element threshold, in average, 10 keV
Natural -background for 6000 Califa elements equal to 1.0*10^6 events/sec ( > 50 keV). What is the trigger structure??
Spectroscopic threshold – 25 keV
Noise – 8.7 keV (FWHM) for 44-51% of Light Collection. 10x30x130x15x42 mm**3 CsI(Tl)
Noise – 4.3 keV (FWHM) - Moszynski., NIMA 485(2002)504 in case of 100% of Light Collection. 0.8x10x10 mm**2 CsI(Tl) .Threshold –10 keV
C hannels
X - l ine, 59. 5 keV
B ackround for 2 hour s
T hreshold25 keV
C al i fa-5 C sI (T l )
0
2
4
6
8
10
12
20 40 60 80 100 120 140 160 180 200
10-1
1
10
10 2
10 3
20 40 60 80 100 120 140 160 180 200
Califa-5 element. Spectrum of Am241 X-line ( 59.5 keV). Spectroscopic threshold around 25 keV
-background, accumulated during 2 hours, low-energy part, 170 1/sec
A threshold of 100 keV a large reduction of background
Other points to be raised for discussion (LU, 16 April 2008)
-The possible use of PD+PA(ALICE/PHOS)
- The optional choice of 210 cm CsI(Tl) for forward cap
-The in-beam tests at TLS and TDU
- The DEMONSTRATOR(s) and their interface to Si tracker, FEE and DAQ
CWG, 16 April 08, LU