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