Post on 25-Dec-2015
Development of FARICH-detector for the ALICE experiment at CERN
A.I.Berlev, T.L.Karavicheva, E.V.Karpechev, Yu.V.Kupchinskiy, A.B.Kurepin, A.N.Kurepin, A.I.Maevskaya,
Yu.V.Musienko, V.I.Razin, A.I.Reshetin, D.A.FinogeevInstitute for Nuclear Research of the Russian Academy of Sciences,
Moscow, Russia
A.F.Danilyuk, V.L.KirillovBoreskov Institute of Catalysis
S.A.Kononov, E.A.Kravchenko, A.P.OnuchinBudker Institute of Nuclear Physics,
Novosibirsk, Russia
Feb.27 – March5, 2008 Development of FARICH-detector for the ALICE experiment at CERN Andrey ReshetinINSTR08, Novosibirsk, RUSSIA (slide 1) Institute for Nuclear Research, Moscow
Outline
☻ ALICE HMPID-system upgrade☻ FARICH (Focusing Aerogel RICH) concept ☻ Simulation of a multi-layer aerogel radiator
for FARICH-detector☻ Design project of FARICH-detector with MRS APDs☻ MRS APD properties (CPTA, Moscow)☻ Winston-cone holes for light-collection☻ Cooling system for MRS APD☻ Schedule for the FARICH beam test at CERN
Feb.27 – March5, 2008 Development of FARICH-detector for the ALICE experiment at CERN Andrey ReshetinINSTR08, Novosibirsk, RUSSIA (slide 2) Institute for Nuclear Research, Moscow
ALICE HMPID-system upgrade
2 m
Each of 7 HMPID modules (42 windows):
- has sizes of about 1.5 x 1.0 m
- covered azimuth angle Δθ ≈ 18 degrees
Each HMPID window covers Δθ ≈ 6 degrees (solid angle ΔΩ ≈ 10 msr)
There are free modules (windows) for upgrade with Very High Momentum PID-system
Free modules (windows) for VHMPID upgrade
Ref: D.Cozza et al. (HMPID Collaboration) NIM A 502 (2003) 101-107.Feb.27 – March5, 2008 Development of FARICH-detector for the ALICE experiment at CERN Andrey ReshetinINSTR08, Novosibirsk, RUSSIA (slide 3) Institute for Nuclear Research, Moscow
ALICE HMPID-system upgrade
ALICE HMPID-system
uses the proximity type geometry without focusing,consists of:- container with liquid C6F14 radiator (n = 1.26) and quartz window- photosensitive detector on the basis of MWPC with CsI-photocathode plane segmented into the pad readout structure
(sizes of the pad are 8 x 8.4 mm)
Rings measured during the HMPID beam test run
ALICE HMPID-system performances (Results of HMPID beam test runs at CERN):
● On an average 16 pe / ring per event track ● Single photon resolution – about 12 mrad ● Cherenkov angle resolution – about 3 mrad ● Particle identification:
π/K separation
in the momentum range from 1 to 3 GeV/c K/p separation
in the momentum range from 1.5 to 5 GeV/c
Feb.27 – March5, 2008 Development of FARICH-detector for the ALICE experiment at CERN Andrey ReshetinINSTR08, Novosibirsk, RUSSIA (slide 4) Institute for Nuclear Research, Moscow
An important experimental direction of the study in physics of heavy ion collisions is the measurement of the yield of high-Pt particles. The main problem is
to study the dominant mechanism of parton energy loss in compressed nuclear matter.
“Jet quenching effect” by RHIC PHENIX Collaboration (K.Adcox et al., Phys.Rev.Lett. 88 (2002) 022301)
gives the indication on a different loss of energy by partons and gluons in nuclear matter.
Data by RHIC STAR Collaboration (C.Adler et al. Phys.Rev.Lett. 89 (2002) 202301)
show the effect of supression of high-Pt particles up to a momentum
≥ 10 GeV/c (!)
ALICE HMPID-system upgrade
Physical requirements to characteristics of the VeryHMPID system
π/K separation in the momentum range from 3 to 10 GeV/c K/p separation in the momentum range from 5 to 14 GeV/c
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 5) Andrey Reshetin, INR, Moscow
CaF2 window
CsI
C4F10CF4
CaF2 window
CsI
C4F10CF4
TIC detector
ALICE HMPID-system upgrade
FARICH detector
There are 2 options for ALICE Very-HMPID-system:
1. Focusing Aerogel RICH (FARICH) detector
and
2. Threshold Imaging Cherenkov (TIC) detector
A.Braem et al. Nucl. Instr. And Meth. A 409 (1998) 426
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 6) Andrey Reshetin, INR, Moscow
FARICH concept First references on this concept:
Belle group: 1. P.Krizan, Aerogel RICH, talk given at Super B Factory Workshop in Honolulu, Hawaii 19-22 January 2004, http://www.phys.hawaii.edu/superb04 2. S.Nishida, et al., Studies of a proximity focusing aerogel RICH for the Belle upgrade, Proceedings of the IEEE Nuclear Science Symposium Rome, Italy, October 17- 22, 2004. 3. T.Iijima, S.Korpar et al., Nucl. Instr. and Meth. A548 (2005) 383. 4. S.Korpar et al., Nucl. Instr. and Meth. A553 (2005) 64-69
Novosibirsk group: started discussions of the use of a multy-layer aerogel – April 2003, Alexander Danilyuk – production of 4-layered aerogel May 2004 A.Yu. Barnyakov et al., Nucl. Instr. and Meth. A553 (2005) 70.
Chargedparticle
Aerogel
n1 n2
Photon detector
The main goal of the FARICH concept is - to increase the number of photons by using thicker radiator; - to focus Cherenkov cones on the detector sensitive plane without degrading the angle resolution.
The FARICH proximity focusing type geometry was proposed. - the use of several layers of aerogel with gradually increasing refractive indices, n3 > n2 > n1 allows to focus Cherenkov cones of the same radius; - refractive indices are determined by different proximity gaps.
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 7) Andrey Reshetin, INR, Moscow
Simulation of a multi-layer aerogel radiator for FARICH-detector
GEANT4 package was used to estimate the performance of the FARICH-detector
Input conditions and parameters for optimization of aerogel radiators:- photo-sensor array of MRS APDs with 100% geometrical efficiency;
- the measured APD photon detection efficiency (PDE, [%]) as function of the light
wavelength;
- MRS APD with/without WLS-paint on the entrance window;
- the distance between the layer No.2 and the focus plane: D = 500 mm (see Fig.)
The following aerogel parameters were considered:
● scattering length λ(sc) = 5 cm at light wavelength 400 nm;
● absorption length λ(abs) = 400 cm “ “ 400 nm;
● total radiator thickness T ≤ 50 mm;
We investigated the response of silica aerogel radiators made of 2 to 4 layers to kaons of momentum P = 10 GeV/c.Pion/kaon and kaon/proton separation power values for momenta 10 GeV/c and 14 GeV/c, respectively, have been calculated.
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 8) Andrey Reshetin, INR, Moscow
Simulation of a multi-layer aerogel radiator for FARICH-detector
The simulated dependences of the
angle resolution per track σ and
number of photoelectrons N pe
on a total aerogel thickness T [mm]
are shown in Figures
Conclusion:
at total aerogel thickness up to 30-35mm
the angle resolution is almost same
for 2-, 3- and 4- aerogel layers
(difference: 10-15 %).
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 9) Andrey Reshetin, INR, Moscow
Simulation of a multi-layer aerogel radiator for FARICH-detector
Radiator version
N layers T total
mmNpe r, мм
σr, 1pe,
мм
Ring area, mm2
(+/_3σ)
σ(θ), mrad
π/K sep,
σ
n=1.03 1 23.5 15 120.5 1.9 8.63E+03 0.92 4.9 2 33.1 20 121.3 1.5 6.86E+03 0.65 7.1 3 45.8 26 121.5 1.4 6.41E+03 0.53 8.7
n=1.03 with WLS 1 38.5 29 118.6 3.1 1.39E+04 1.10 4.2 2 52.6 35 120.1 2.5 1.13E+04 0.81 5.6
1 22.3 24 156.5 2.5 1.48E+04 0.91 3.9
n = 1.05 2 35.6 35 157.2 2.0 1.19E+04 0.61 5.8 3 50.0 47 157.4 1.9 1.13E+04 0.49 7.2
n=1.05 with WLS 1 40.2 49 153.6 4.1 2.37E+04 1.04 3.4
Results of the simulation for momentum 10 GeV/c
where: r is the average radius of the Cherenkov ring; σr, 1 pe is the mean deviation of the Cherenkov radius (for single photon). S is the ring area; Npe is the number of detected photoelectrons; σӨ is Cherenkov angle resolution in mrad; π/K sep is the pion/kaon separation power in number of standard deviations
for momentum 10 GeV/c.
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 10) Andrey Reshetin, INR, Moscow
Design project of FARICH- Prototype with MRS APDs
CONSTRUCTIONAL and
FUNCTIONAL PARTSof the FARICH PROTOTYPE
The FARICH Prototype consists of
1. Light-isolating box
2. Thin carbon entrance window for the beam
3. Radiator of Cherenkov photons (2-layer silica aerogel) on the support frame
4. Light-collecting plane with the matrix of Winston-cone holes
5. Photosensitive coordinate matrix with MRS APDs 6. Plate with LV-supply dividers and front-end electronics
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 11) Andrey Reshetin, INR, Moscow
Design project of FARICH-prototype with MRS APDs
MRS APD produced by CPTA
Light-collecting Cell(Winston-cone hole)
Diam. 3 mm ↓
Diam. 1.1 mm
Sensitive area: ≈ 1 mm2600 pixels
FARICH-Prototype is developing in frameworks of INTAS-CERN Research Project No. 05-103-7544:
“Development of a Cherenkov detector to extend
the PID Capability of ALICE beyond 5 GeV/c”
Proposal has been submitted to INTAS in September, 2005and this Development is the INTAS property.
We would like to thank the Belle group for very useful
test results obtained in the similar Project. (!) ↓ ↓ ↓ ↓ ↓
Belle group:
1. S.Korpar et al., Silicon photomultiplier as a position sensitive detector of cherenkov photons. “RICH2007”, Trieste, Italy, October 15-20, 2007.2. T.Iijima et al., Geiger-mode APD as a RICH Photodetector. International Workshop on New Photo-Detectors (PD07) June 28, 2007
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 12) Andrey Reshetin, INR, Moscow
Design project of FARICH-prototype with MRS APDs
R(max) = 165 m
m
R(min) =
133 mm
Results of simulation for 2 aerogel layers:
n1 = 1.050 ; n2 = 1.047(T1 = 17.2 mm, T2 = 17.8 mm)
K-mesons with momentum 10 GeV/c:r = 157 mm (σ = 2.0 mm for 1 pe)Protons with momentum 5 GeV/c:r = 135 mmβ = 1.0 r (limit) = 160 mmAerogel thickness (2 layers) T = 35.6 mmN(pe) = <35> pe / ring (per event track)Angle res. for K-mesons 10 GeV/c σ=0.61 mrad π/K separation 5.8 σ
Taking into account simulation results the design Geometry for the Prototype Photosensitive Matrix has been chosen:
Photosensitive ring is divided by 4 sectors: R(min)=133 mm, R(max)=165 mm, S=120 cm2Total amount of MRS APDs: 900 - on the Ring, 25 – in centreGeometrical efficiency: about 50% (APD cell sizes) and about 47% (ring sector sizes)We will have the total amount of photoelectrons: <8-9> pe / ring per event track for Prototype Matrix and <16-18> pe / ring for full scale Matrix
w
Prototype Photosensitive Matrix
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 13) Andrey Reshetin, INR, Moscow
MRS APD performances (CPTA, Moscow)
Measurements of MRS APD performances were carried outbyYu.Musienko on test benches at CERN APD Lab andD.Finogeev and Yu.Kupchinskiy
at INR, Moscow
As example the dependence of the photondetection efficiency PDE on a light wavelength for MRS APDs of differenttypes is shown.
We plan to use “50V-APD” for our FARICH Prototype
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 14) Andrey Reshetin, INR, Moscow
MRS APD performances (CPTA, Moscow)
For tests, the entrance windows of a few
APDs was covered by a special wave
length shifter film (paint) developed by
Photonique SA (Geneva).
Dependences of the PDE on a light
wavelength for MRS “50V-APDs” and
the “50V-APDs” + WLS-paint are shown.
As result the WLS-film increases the
PDE of about two times at 450 nm
and about ten times
in the range 300-400 nm.
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 15) Andrey Reshetin, INR, Moscow
MRS APD performances (CPTA, Moscow)
0.6 mrad0.9 mrad
Nevertheless the simulation results show that angle resolution for MRS APD with WLS is degraded: to 0.9 mradas compared 0.6 mrad for APD without WLS
The reason: a big dispersion of the reflective index in aerogel n = f(λ) for a blue light (?)Or a big forward scattering for a blue light (?)
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 16) Andrey Reshetin, INR, Moscow
Dependences of the Dark current, Gain and PDE (410 nm) on Bias [V]
for “50V - MRS APD” with WLS-paint produced by CPTA (Moscow).
For the set of 925 MRS APD we use optimal Bias in a range of
about 50-51 V
47 48 49 50 51 52 47 48 49 50 51 52 47 48 49 50 51 52
MRS APD performances (CPTA, Moscow)
Dark current [mkA] APD Gain (x10^6) PDE (410 nm) [%]
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 17) Andrey Reshetin, INR, Moscow
Winston-cone holes for light-collection
Winston-cone hole:Diam. 3 mm → Diam. 1.1 mm
For testing the prototype Winston-cone holes
with parabolic inner surface in aluminium and stainless steel
plates have been produced.
Winston-holes in aluminium plate had 4 types of the treatment of an inner surface:
- treatment with special (14 class) polishing- treatment with polishing of a tool edge;- pressure method;- pressure method with polishing.
Winston-holes in stainless plate were polished by 4 different methods of electric-plasma polishing.
parab
olic in
ner su
rface
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 18) Andrey Reshetin, INR, Moscow
Winston-cone holes for light-collection
For APD without Winston-
cone light collection (open
version) the mean value of
amplitude spectrum is
in 120 ch.
<N> = 600 ch – for stainless
steel Winston-cone holes
Pedestal: <N(ped)> = 40 ch.
Experimental geometrical factor:
≈ 7.0 +/_ 0.36
Calculated geometrical factor:
≈ 7.44
Estimation of light collection
efficiency: ≈ 94 +/_ 5%
Relative dependence of the light collection efficiency on Winston-
cone holes of different types
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 19) Andrey Reshetin, INR, Moscow
Cooling system for MRS APDLay-out of the Cooling system
is presented in Fig.1
1. Copper plate
2. Heat Exchanger: Peltier module (131 W)
3. Cooler: Water radiator4. MRS APD
5. Thermo-pair sensor
The temperature Tmin = - 17 ºC
around the CPTA APD position
was achieved
Fig.1
Water micro-tubes
2
1
3
4 5
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 20) Andrey Reshetin, INR, Moscow
Cooling system: heat exchanger and cooler1. Heat Exchanger: Peltier Module “Drift 1.05”
Work performances:Power = 131.0 WSizes: 40×40×3.5 mmVoltage = 24.6 VCurrent = 8.6 A∆T = 70 ºC
2. Cooler a) air cooler b) water cooler
Results of CPTA APD cooling (APD coupled with copper plate ∆h = 1 mm)
0.08-17water option
0.20+8air option
1.66+22room
Dark noise [MHz]T ºC
Cooling system for MRS APD
At -17 C Dark noisecan be decreased in about 20 times(until 0.08 MHz) (!)
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 21) Andrey Reshetin, INR, Moscow
Schedule for the FARICH beam test at CERN
Beam channel – ALICE test beam channel T10
Beam particles – negative pions
(electrons)
Momentum range - 2 ÷ 10 GeV/c
Beam intensity -
200-500 particles/spill
Beam time –
October-November, 2008
20 shifts
INSTR08, Novosibirsk, Russia (Feb.27 – March5) (slide 22) Andrey Reshetin, INR, Moscow