electroluminescence yields in micromegas , thgem and gem
DESCRIPTION
Electroluminescence yields in MicroMegas , THGEM and GEM. H. Natal da Luz 1 , C.M.B. Monteiro 1 , J.M.F. dos Santos 1 , C. Balan 1 , E.D.C. Freitas 1 , J.F.C.A. Veloso 2 , A. Breskin 3 , T. Papaevangelou 4 , I. Giomataris 4. 1 University of Coimbra, Portugal - PowerPoint PPT PresentationTRANSCRIPT
7th RD51 Collaboration Meeting13-15 April, 2011, CERN
7th RD51 Collaboration Meeting13-15 April, 2011, CERN
H. Natal da Luz1, C.M.B. Monteiro1, J.M.F. dos Santos1, C. Balan1, E.D.C. Freitas1, J.F.C.A. Veloso2, A. Breskin3,
T. Papaevangelou4, I. Giomataris4
1University of Coimbra, Portugal2University of Aveiro, Portugal
3Weizmann Institute of Sciences, Israel4Centre d’Études Nucléaires de Saclay, France
Electroluminescence yields in MicroMegas, THGEM and GEM
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 2
Outline
Motivation; Experimental setups with different
MPGDs and UV sensitive LAAPDs; Methods for determination of Electro-
luminescence yields; Results; Conclusions.
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 3
Motivation
Rare event experiments (eg.: dark matter search, neutrinoless double beta decay) can take advantages of reading charge and scintillation light produced by MPGDs;
Decoupling of electronic noise; Usually much better SNR.
7th RD51 Collaboration Meeting13-15 April, 2011, CERN
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 4
Gap: 50 mmHole diameter: 25 mm
Thickness: 0.4 mmHole diameter: 0.4 mmRim: 0.1 mm
MicroMegasTHGEM/GEM
MPGD scintillation vs. charge readout
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 5
Charge (a) and scintillation (b) pulse-height distributions in MM
LAAPD gain ~ 30
0 100 200 300 400 500 600 7000
500
1000
0
500
0
500
0 100 200 300 400 500 600 700b)
Channel Number
2 bar
Co
un
ts
6 bar
10bar
0 100 200 300 400 500 600 7000
500
10000
500
0
500
10000 100 200 300 400 500 600 700
a)
Channel Number
2 bar
Co
un
ts
6 bar
10bar
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 6
MM EL Yield
0 100 200 300 400 500 600 7000
500
1000
0
500
0
500
0 100 200 300 400 500 600 700b)
Channel Number
2 bar
Cou
nts 6 bar
10bar
0 100 200 300 400 500 600 7000
500
10000
500
0
500
10000 100 200 300 400 500 600 700
a)
Channel Number
2 bar
Cou
nts 6 bar
10bar
1 2
xE
x
ScUVeff w
ENY
QE
N
A
AN XRe
X
ScUV
,
3, 101.6
eV 62.3
eV 22100XReN
------------------------
APD
toteUV G
GQEN 1
,
ScUVeff NY
2
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 7
MM charge gain in Xe
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 8
Maximum charge gain Vs pressure (Xe)
0 1 2 3 4 5 6 7 8 9 10 11100
101
102
103
104
0 1 2 3 4 5 6 7 8 9 10 11
100
101
102
103
104
Max
imu
m G
ain
Pressure (bar)
MM-charge MM-scint S-THGEM S-GEM 3-GEM MHSP
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 9
MM Charge gain fluctuations (Xe)
300 400 500 600 700 800 9000,10
0,15
0,20
0,25
0,30
0,35
0,40
0,45
0,50
0,55
0,60
300 400 500 600 700 800 900
0,10
0,15
0,20
0,25
0,30
0,35
0,40
0,45
0,50
0,55
0,60
a)
1 bar 2 bar 3 bar 4 bar 5 bar 6 bar 7 bar 8 bar 9 bar 10 bar
En
erg
y R
es
olu
tio
n (
Ch
arg
e)
VMM
(V)
22 keV X-rays
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 10
MM gain in scintillation-readout (Gtot = primary charge/charge out from LAAPD)
LAAPD gain ~ 30
300 400 500 600 700 800 900102
103
300 400 500 600 700 800 900
102
103
b)
1 bar 2 bar 3 bar 4 bar 5 bar 6 bar 7 bar 8 bar 9 bar 10 bar
Ga
in -
sc
inti
lla
tio
n c
ha
nn
el
VMM(V)
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 11
Charge-to-scintillation gain ratio
300 400 500 600 700 800 900 1000
0,1
1300 400 500 600 700 800 900 1000
0,1
1
1 bar 2 bar 3 bar 4 bar 5 bar 6 bar 7 bar 8 bar 9 bar 10 barG
ain
Ra
tio
(C
ha
rge
/Sc
inti
lla
tio
n)
VMM(V)
Lower E/p favours excitations
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 12
Absolute EL Yield “out” of MM (Xe)
300 400 500 600 700 800 900 1000
102
103
300 400 500 600 700 800 900 1000
102
103
10 bar9 bar
8 bar7 bar
6 bar
5 bar
4 bar
3 bar2 bar
1 bar
Yef
f (
ph
oto
ns
/ p
rim
ary
e- )
VMM
(V)
• Double mesh, uniform field scintillation gap yields
466 photons/e-/cm @ 4.1 kV/cm/bar
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 13
THGEM Gains in Xe
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
0 500 1000 1500 2000 2500 3000
Ab
so
lute
Ga
in
DVTHGEM (V)
1.0 bar
1.5 bar2.0 bar
2.5 bar
1.0 bar
2.0 bar 3.0 bar
APD gain ~150
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 14
THGEM EL yield in Xe
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
0 500 1000 1500 2000 2500 3000
Ele
ctr
olu
min
es
ce
nc
e y
ield
(P
h /
pri
ma
ry e
- )
D VTHGEM (V)
1.0 bar
1.5 bar2.0 bar
2.5 bar
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 15
Statistical fluctuations in THGEM
0
5
10
15
20
25
30
35
40
0 500 1000 1500 2000 2500
En
erg
y R
es
olu
tio
n (
%)
DVTHGEM (V)
2.0 bar
2.5 bar
1.5 bar1.0 bar
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 16
GEM gain in Xe
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1.0E+05
1.0E+06
100 200 300 400 500 600 700
Ga
in
DVGEM (V)
1.0 bar1.5 bar
2.1 bar2.5 bar
1.0 bar1.5 bar
2.1 bar
2.5 bar
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 17
GEM EL yield (Xe)
1.0E+00
1.0E+01
1.0E+02
1.0E+03
1.0E+04
100 200 300 400 500 600 700
Ele
ctr
olu
min
es
ce
nc
e y
ield
(P
h /
pri
ma
ry e
- )
DVGEM (V)
1.0 bar1.5 bar
2.1 bar2.5 bar
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 18
GEM statistical fluctuations
0
10
20
30
40
50
60
100 200 300 400 500 600 700 800 900
En
erg
y R
es
olu
tio
n (
%)
DVGEM(V)
1.0 bar charge
1.5 bar charge
2.0 bar charge
2.5 bar charge
1.0 bar scint
1.5 bar scint
2.1 bar scint
2.5 bar scint
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 19
THGEM in Ar
1.0E+02
1.0E+03
1.0E+04
1.0E+05
1.0E+06
0 500 1000 1500 2000 2500
Abs
olut
e G
ain
D VTHGEM (V)
1.1 bar1.5 bar
2.1 bar2.5 bar
1.0 bar
1.0E+01
1.0E+02
1.0E+03
1.0E+04
1.0E+05
0 500 1000 1500 2000 2500
Elec
trolu
min
esce
nce
yie
ld
(Ph
/ prim
ary
e- )
D VTHGEM (V)
1.1 bar1.5 bar
2.1 bar 2.5 bar
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 20
GEM in Ar
1.0E+01
1.0E+02
1.0E+03
1.0E+04
100 200 300 400 500 600 700
Gai
n
DVGEM (V)
1.0 bar2.0 bar
1.0 bar 2.0 bar
1.5 bar
2.5 bar
3.0 bar
1.0E+00
1.0E+01
1.0E+02
1.0E+03
200 250 300 350 400 450 500 550
Elec
trol
umin
esce
nce
yie
ld
(Ph
/ pri
mar
y e
- )
DVGEM (V)
1.0 bar2.0 bar
2.5 bar
1.5 bar
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 21
Conclusions
Table I – Maximum gain and scintillation yield for GEMs and THGEMs
operating in argon and xenon at 1 bar and 2.5 bar.
Xenon Argon
1 bar 2.5 bar 1 bar 2.5 bar
GEM Gain 1.5 × 105 4 × 104 5 × 103 5 × 103
Yield 6 × 103 1.5 × 103 3 × 102 3 × 102
THGEM Gain 1.2 × 106 4 × 104 1.2 × 105 3 × 104
Yield 7 × 104 2 × 103 1.5 × 104 4 × 103
• Double mesh, uniform field scintillation gap yields
466 photons/e-/cm @ 4.1 kV/cm/bar
7th RD51 Collaboration Meeting13-15 April, 2011, CERN 22