Ageing studies since June 2006

1
Ageing studies since June 2006

• Comparisons HD NIKHEF
• damage, patterns, analyses
• Oxygen results
• Outgassing

2
55Fe Comparison NIKHEF HD
Damage NIKHEF,70nA,30hr (17) HD,110nA, 50hr HD,110nA,70hr
I. HD 10 12 35
Agreement?
HD
NIKHEF
3
Compare large area irradiation

• HD 9 keV X ray, radius 50cm, 140 hrs, 50 nA
  (1520V) 80 damage
• NI 2mCu 90Sr, radius 30cm, 14 hrs, 50 nA
  (1600V) 10 damage
• Both damage upstream,
• Both more damage in the center of the module

gas
4
Check region channel 1-10

• 3 measurements
• Before irradiation
• After irradiation
• Rescan

Ratio 2/1
Ratio 3/1
Ratio 3/2
ok
lowish

• Conclusion
• Measurement 2 is suspiciously low around ch1-10
• The damaged area worsened from 0.3 to 0.25

5
Single wire

• Disconnected all wire, but wire 32.
• Conclusion
• Ageing occurs independent of neighbors
• Possibly can use a simple test module of 1 straw
  to investigate materials
• Spots at 20, 40, 50 cm unclear

6
55Fe Comparison NIKHEF HD
Damage NIKHEF,70nA,30hr (17) HD,110nA,95hr
20 50
Agreement?
HD
NIKHEF
7
90Sr Comparison NIKHEF - HD
Damage NIKHEF,120nA,22hr (16) HD,70nA,27hr
30 10
Agreement?
HD
NIKHEF
8
Analysis Comparison NIKHEF - HD
Irradiation 22hrs
Ratio of gain
NIKHEF analysis
HD analysis
Different definition of rings
9
Analysis Comparison NIKHEF - HD
Ratio of gain
Irradiation 30hrs
NIKHEF analysis
HD analysis
Different definition of rings
10
Small current
22 hrs, 125 nA 90Sr (test16)

• Conditions
• Flow Ar/CO2 20 l/hr
• 1600V, 70/30, 90Sr
• 22 hrs, 125 nA 10mC
• 166hrs, 2.5 nA 1.5mC
• Conclusions
• Maximum damage at small currents

166 hrs, 2.5 nA 90Sr
Current profile
11
Flush with Oxygen Ar/CO2/O2 70/27.5/2.5

• Conditions
• 1600V, 90Sr
• Ar/CO2
• 70/30 20 l/hr
• Ar/CO2/O2
• 70/27.5/2.5 10 l/hr
• Conclusions
• With oxygen slower ageing
• NB. Gas flow is lower

22 hrs, Ar/CO2 70/30 (test16)
66 hrs, Ar/CO2/O2 70/27.5/2.5 (test16)
Current profile
12
Flush with Oxygen
68 hr _at_13cm
Gas flow

• Conditions
• Flow Ar/CO2/O2 10 l/hr
• 2mCu, 90Sr source
• Conclusions
• Oxygen ages slowly

68 hr _at_13cm 22 hr _at_23cm
68 hr _at_13cm 46 hr _at_23cm
Compare to result from Heidelberg
90 hr _at_13cm 46 hr _at_23cm
13
Flush with Oxygen,vary gas flow
Ar/CO2 70/30, 46hrs, 20 l/hr

• Conditions
• Flow Ar/CO2/O2 70/27.5/2.5
• 2mCu, 90Sr source, 68 hrs
• Conclusions
• Oxygen ages slower by factor 3
• Larger flow, larger ageing

20 l/hr
10 l/hr
14
Did oxygen flushing prevent ageing?
After oxygen flushing, irradiated 16 hrs

• Test to prevent ageing
• Conditions
• Flow Ar/CO2 20 l/hr
• 2mCu, 90Sr source on module surface, 16 hours
• Conclusions
• Ageing as usual.
• Irradiation after oxygen flushing does not
  prevent ageing

gas
L
U
No oxygen flushing, irradiated 22 hrs
Ratio
Zoom
15
Long term? Outgassing?
3B (30) - 12/4/2006 15hr
3B (7) - 18/1/2006 - 15hr

• Conditions
• Flow Ar/CO2 70/30 20 l/hr
• January in cleanroom
• Feb now in lab
• 2mCu, 90Sr source

3A (3) - 15/4/2006 23hr
3B (17) - 23/2/2006 - 15hr
3B (28) - 21/3/2006 21.5hr
3A (19) - 23/5/2006 22hr
16
Long term?Outgassing?

• Conditions
• Flow Ar/CO2 70/30 20 l/hr
• January in cleanroom
• Feb now in lab
• 2mCu, 90Sr source

3A (3) - 15/4/2006 23hr
3B (7) - 18/1/2006 - 15hr
3A (19) - 23/5/2006 22hr
3B (17) - 23/2/2006 - 15hr
3B (28) - 21/3/2006 21.5hr
3A (27) - 19/6/2006 16hr
3A (29) - 15/8/2006 20hr
3B (30) - 12/4/2006 15hr
17
Damage vs Time(module 3)
Mod Date Loc I(nA) Time (hrs)
1 3B 18Jan cleanroom 190 15
2 3B 23Feb Lab 150 15
3 3B 21Mar Lab 150 21.5
4 3B 12Apr Lab 150 15
5 3A 15Apr Lab 180 23
6 3A 23May Lab 140 22
7 3A 19Jun Lab 150 16
8 3A 15Aug Lab 150 20

• Conditions
• Flow Ar/CO2 70/30 20 l/hr
• 2mCu, 90Sr source
• January in cleanroom
• Feb now in lab
• Flushed for 140 days
• 65,000 liter gas

normalization?
15hr
16hr
careful... Also the tape region is integrated
here!
15hr
16hr

• Point 4,7 is a bit strange
• Only 15,16 hrs of irradiation
• More damage

18
Ageing (22hr) before vacuum treatment
Put 1m-module 1day, 6days under vacuum

• Conditions
• Flow Ar/CO2 70/30
• 2mCu, 90Sr source
• Conclusions
• Forced outgassing in vacuum helps??

Ageing (19hr) after vacuum treatment
Ageing (19hr) after 6 days vacuum treatment
Ageing (18hr) additional 50hrs flushing
Damage Before After 1 day After 1 day After 6 days After 6 days After 6 days After 6 days
RelGain Loss RelGain Loss RelGain Loss RelGain Loss
I. HD 0.87 -13 0.79 -21 0.93 -7 0.98 -2
II. Max 0.72 -28 0.68 -32 0.86 -14 0.95 -5
III. Sum -6.4 -12.7 -2.3 3.4
Note different scale!
19
Irradiating after reversing gas flow

• Conditions
• Flow Ar/CO2 70/30
• 2mCu, 90Sr source
• Conclusions
• Reversing gas flow makes little recovery

Gas flow
84 hrs irradiation
Netto effect
Gas flow
91 hrs irradiation
20
Additional damage after flushing?No irradiation!

• Conditions
• Flow Ar/CO2 70/30
• 2mCu, 90Sr source
• Flush for 20 days at 20 l/hr between July 26 and
  August 15
• Conclusions
• Additional damage after flushing

Ratio of scans from Aug15 / Jul26
Original damage from irradiation
21
Different F-module 002Test effect of fast
flushing

• Conditions
• Flow Ar/CO2 70/30
• 2mCu, 90Sr source20hrs
• Flushing
• 140 l/hr
• Total 21,000 l of N2
• Conclusions
• Flushing helps
• gas flow not important

Damage Before After 7,400 liter After 7,400 liter After 21,000 liter After 21,000 liter
Rel Gain Loss Rel Gain Loss Rel Gain Loss
I. HD 0.54 -46 0.68 -32 0.66 -34
II. Max 0.30 -70 0.43 -57 0.41 -59
III. Sum -20.8 -16.1 -11.1
Ageing (19hr) before flushing
Ageing (21hr) after 21,000 l flushing
Ageing (19hr) after 7,400 l flushing
22
Damage vs TimeIrradiation profiles
Mod Date Loc I(nA) Time (hrs)
1 2A 22Jun cleanroom 230 19
2 2A 28Jun cleanroom 160 19
3 2A 4Jul cleanroom 200 21
4 2A 27Jul cleanroom 200 20
5 2A 15Aug cleanroom 170 19

• Conditions
• Flow Ar/CO2 70/30 20 l/hr
• 2mCu, 90Sr source
• Between 22Jun and Jul27
• Flushed with N2 with 140 l/hr

23
Improvement with Time
Jun 22

• Conditions
• Flow Ar/CO2 20 l/hr
• 2mCu, 90Sr source
• Between 22Jun and Jul27
• Flushed with N2 with 140 l/hr

Jun 28
Mod Date Loc I(nA) Time (hrs)
1 2A 22Jun cleanroom 230 19
2 2A 28Jun cleanroom 160 19
3 2A 4Jul cleanroom 200 21
4 2A 27Jul cleanroom 200 20
5 2A 15Aug cleanroom 170 19
6 2A 28Aug cleanroom 170 20
Jul 4
Jul 27
Aug 15
Aug 28
24
Damage vs TimeCompare mod 2 and mod 3
Mod Date Loc I(nA) Time (hrs)
1 2A 22Jun cleanroom 230 19
2 2A 28Jun cleanroom 160 19
3 2A 4Jul cleanroom 200 21
4 2A 27Jul cleanroom 200 20
5 2A 15Aug cleanroom 170 19

• Conclusions
• Module 2 improves faster than module 3

3rd 10 longer irr
Compare to result from Heidelberg
Module 63
36.2 m3
100 days