Pavia 25/11/2003 Davide Piccolo INFN Napoli
Status of assembling and Chamber results at HT
Pavia 25/11/2003
Davide Piccolo
Pavia 25/11/2003 Davide Piccolo INFN Napoli
outlook
• Status of the assembling operation at HT
• Tests at HT
• Summary of the results
• Problems and peculiarities
Pavia 25/11/2003 Davide Piccolo INFN Napoli
HT chambers location
HT Bari
PaviaCERN
11 chambers
4 chambers back
3 chambers
8 chambers
8 chambers ready
30 chambers produced12 chambers at HT (9 ready,
3 to be checked)3 chambers at CERN (no cosmic test)7 chambers at PAVIA (tested ok)8 chambers at Bari (ready to be tested)
Pavia 25/11/2003 Davide Piccolo INFN Napoli
Pavia 25/11/2003 Davide Piccolo INFN Napoli
Tests at HT
• Continuity test: strip continuity check
• LV test• Gas test• Cooling test
• HV scan: I vs HV• Stability test: monitor
of dark current at 9500 Volts for one hour
• Test of single rate strip by strip
• Threshold test
Tests during assembling Tests after assembling
Pavia 25/11/2003 Davide Piccolo INFN Napoli
HV scan
0
0,5
1
1,5
2
2,5
3
3,5
4
1
11 21 31 41 51 61 71 81 91
101
111
121
131
141
151
161
171
181
191
201
211
221
231
241
251
261
271
281
291
301
311
321
time (10 sec)
I (uA
)
forw up
forw down
back up
back down
1000 V
2000 V
4000 V
3000 V
9500 V
9200 V
9000 V
8000 V
7000 V
6000 V
5000 V
HV scan
Pavia 25/11/2003 Davide Piccolo INFN Napoli
Stability testCHAMBER 173
0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
1
10
19
28
37
46
55
64
73
82
91
10
0
10
9
11
8
12
7
13
6
14
5
15
4
16
3
17
2
18
1
19
0
19
9
20
8
21
7
22
6
23
5
24
4
25
3
26
2
27
1
28
0
28
9
29
8
30
7
31
6
HV (Volts)
I (u
A)
ant sup
ant inf
post sup
post inf
Temp 22 degrees
Pavia 25/11/2003 Davide Piccolo INFN Napoli
Analysis program under development
• Convert the HT data format in the standard CMS RPC DataBase format.
• Measure average and RMS of the dark current for every HV step
• In the future will include single rate measurement analysis
Pavia 25/11/2003 Davide Piccolo INFN Napoli
rms chamber 173
0
0,01
0,02
0,03
0,04
0,05
0,06
0,07
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
HV (Volts)
rms
I (u
A)
forw up
forw down
back up
back down
chamber 173
0
0,5
1
1,5
2
2,5
3
3,5
4
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
HV (Volts)
I (u
A)
forw upforw downback upback down Average dark current vs HV
RMS dark currentvs HV
Pavia 25/11/2003 Davide Piccolo INFN Napoli
temperature
0
5
10
15
20
25
30
35
1 5 9
13
17
21
25
29
33
37
41
45
49
53
57
61
65
69
73
77
81
85
89
93
97
10
1
10
5
10
9
chamber under test
tem
pe
ratu
re (
ce
lsiu
s)
temperatureSUMMARYRESULTS
172
34
37
Pavia 25/11/2003 Davide Piccolo INFN Napoli
Chamber 179 (double gap replaced)chamber 179
0
0,5
1
1,5
2
2,5
3
3,5
1 4 7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
52
55
58
61
64
67
70
73
time (10 sec)
I (u
A)
forw up
forw down
back up
back down
back down OFF
Discharges On frame
HV = 9500 V.
Pavia 25/11/2003 Davide Piccolo INFN Napoli
Noise rate tests
chamber 172 FEB 3B
0
200
400
600
800
1000
1200
1400
1600
0 50 100 150 200 250 300 350
threshold (mV)
rate
(Hz)
strip 10
strip 11
strip 12
strip 13
strip 14
strip 15
strip 16
single rate vs threshold • Fast test single rate vs FEB threshold, with manual frequencymeter.
• Depending from enviromental conditions, noise rate very high or reasonable
• Prototype of 288 channels frequencymeter ready. Very soon will be tested on chamber and included in HT test procedures.
Pavia 25/11/2003 Davide Piccolo INFN Napoli
Main problems• Smd resistor broken on kapton (about 3
strips per bigap). Better situation for new bigaps.
• One cable broken after transportation to Bari (storage bars)
• For 3 chambers replaced a double gap (possible Extracosts at HT !) – Chamber 39 replaced backward bigap
– Chamber 33 replaced backward bigap
– Chamber 179 replaced backward bigap
Pavia 25/11/2003 Davide Piccolo INFN Napoli
Future plans
• 8 chambers ready to be sent to Pavia
• 21 double gaps at HT
• 8 chambers can be assembled
• 5 slots available for storage
• Need trolleys for storage
• We plan to produce at least 15-18 more chambers by the end of the year