xe-tma update andrÉ cortez laboratory of instrumentation and experimental particle physics...
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Xe-TMA updateANDRÉ CORTEZ
Laboratory of Instrumentation and Experimental Particle Physics (LIP-Coimbra)Physics DepartmentUniversity of CoimbraCoimbra, Portugal
RD51 Collaboration – Mini-week
CERN, 7-9 December 2015
Outline
Xenon
TMA
TMA absorption of Xenon Scintillation
Xe-TMA experimental results
RD51 Collaboration – Mini-week
Ion
Mob
ility
Mea
sure
men
t at L
IP C
oim
bra
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 20
0.5
1
1.5
2
2.5
3
3.5
Drift time (ms)
Ampl
itude
(mV)
𝑿𝒆𝟐❑+¿¿E/N=20 Td
7,992 TorrVGEM =16 V
K01 ~ 0,637 cm2V-1s-1 Xe2+
P. Neves, C.A. N. Conde and L.M.N Távora
RD51 Collaboration – Mini-week
Experimental Results: Xe
0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 10
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Drift Time (ms)
Ampl
itude
(mV)
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10
0.5
1
1.5
2
2.5
3
Drift Time (ms)
Ampl
itude
(mV)
E/N=35 Td1,004 TorrVGEM =36 V
Not in Steady State Regime
The reduced mobility has a strong
dependence of the field for pressures
above 3 Torr
It’s not possible to observed any peak in pure TMA for pressures above 3 torr or for low voltages
in the GEM
E/N=35 Td2,992 TorrVGEM =36 V
Ion
Mob
ility
Mea
sure
men
t at L
IP C
oim
bra
K0=0.567±0,013 cm2V-1s-1
Ionization Potential7,8 – 9,4 eV
RD51 Collaboration – Mini-week
Experimental Results: TMA
XenonFlash Lamp Absortion
170 nm
TMA CsI Photocathode
Fluorescent Excitation≈ 235 nm
Low quantum efficiency for
235 nm
Ion
Mob
ility
Mea
sure
men
t at L
IP C
oim
bra
RD51 Collaboration – Mini-week
Experimental Results: TMA
TMA absorption of Xe scintillation
PMT
Gas Chamber
Xe Lamp
G1 – Scintillation field grid
G1
Xe/TMA
Experimental Apparatus
Filter
Wavelength-Shifting Property of TMA
See Nakajima paper [arXiv:1511.02257v1]
RD51 Collaboration – Mini-week
TMA absorption of Xe scintillation
PMT
Xe Lamp
G1 – Scintillation field grid
G1
Xe/TMA
Experimental Apparatus
Filter
Transmittance of the filter used EO U-330 UV – bandpass filter
TMA• Absorbs Xe Scintillation;• Does not re-emit light;• Transmission dependson the amount of TMA and not in the relative abundance;
No signal observed for TMA pressure of 3 Torr.
RD51 Collaboration – Mini-week
Experimental Results: Xe-TMA
RD51 Collaboration – Mini-week
Ion
Mob
ility
Mea
sure
men
t at L
IP C
oim
bra
Interesting results
There is an increase in reduced mobility K0
(Preliminary Results)
Discharges• For the same fields
does not occur for pure TMA or pure Xe.
• Seems to have a dependence with the relative amounts of TMA in the mixture.
0 1 2 3 4 5 6 7 8 9 100.7
0.72
0.74
0.76
0.78
0.8
0.82
% TMA
K0(c
m2
V-1
s-1)
The results obtained for TMA will be presented in NEXT- Experiment Collaboration Meeting in 6th and 7th of
NovemberRD51 Collaboration – Mini-week
Experimental Results: Xe-TMA
Thank you!
RD51 Collaboration – Mini-week