<i>Test Results for Chamber M3R4-50</i></font>

Test Results for Chamber M3R4-50


<font color="#00008B" size="5"><i><b>Bar Codes Table. M3R4-50</b></i></font>

Bar Codes Table. M3R4-50

Chamber
M3R4
Chamber
Bar Code
FEBs
Bar Codes
Date Dressing Comments
50 4UAPNB03400050 4UE20900112930
4UE20900112931
4UE20900112906
31-JAN-07 Chamber is in the Pit


<font color="DarkBlue" size="5"><i><b>Gas Leak Test. M3R4-50</b></i></font>

Gas Leak Test. M3R4-50

<font color="DarkRed" size="4"><i>Limit: <= 2mb/hour</i></font>

Limit: <= 2mb/hour

Chamber Gas Leak
[mb/hour]
Test Date Comments
50 .1 Relative methode


<font color="DarkBlue" size="5"><i><b>Durk Current Test. M3R4-50</b></i></font>

Durk Current Test. M3R4-50

<font color="DarkRed" size="4"><i>Limit: Dark Current (sum of 4 gaps) <=100nA at HV=2.9 kV<br />Gas mixture Ar(40)/CO2(55)/CF4(5)<br />The table presents the currents (in nA) measured in the HV line.</i></font>

Limit: Dark Current (sum of 4 gaps) <=100nA at HV=2.9 kV
Gas mixture Ar(40)/CO2(55)/CF4(5)
The table presents the currents (in nA) measured in the HV line.

Chamber 2.4 kV 2.5 kV 2.6 kV 2.7 kV 2.8 kV 2.9 kV Test Date Comments
50 0 0 0 2 4 10 10-OCT-05 chamber is OK



<font color="#00008B" size="5"><i><b>Cosmic HV-Test. M3R4-50</b></i></font>

Cosmic HV-Test. M3R4-50

Table presents counts averaged over 24 pads measured during 300 sec in the mode AND (AB&CD).
Scan1 - HV(AB) fixed @ 2550 V
Scan2 - HV(CD) fixed @ 2550 V


Chamber Scan 2.35 kV 2.45 kV 2.55 kV 2.65 kV 2.75 kV 2.85 kV Date Plot Comments
50 1
2
315
318
361
351
383
383
409
405
535
592
968
1180
09-FEB-07


Fig.1 Counts/300s averaged over 24 pads.
AB&CD.
Scan1: HV(AB)=2550V
Scan2: HV(CD)=2550V
Fig.2 Counts distribution in 24 pads.
AB&CD.
HV(AB)=HV(CD)= 2550 V
Fig.3 Counts/300s averaged over 8 pads
in FEB1, FEB2, FEB3.
AB&CD
Scan1: HV(AB)=2550V
Scan2: HV(CD)=2550V


<font color="DarkRed" size="6"><i><b>Cosmic Rays and Noise Counts from Internal Counters. M3R4-50</b></i></font>

Cosmic Rays and Noise Counts from Internal Counters. M3R4-50

Table presents counting rates (counts per 100 sec) averaged over 24 pads in bi-gap AB or in bi-gap CD measured with Thr=16fC in all channels applying HV=2550V at one of the gaps (A,B,C,D) while the other gaps are at HV=0. Also presented are the noise rates (counts per 1 sec) averaged over 48 pads (in bi-gap AB and in bi-gap CD) measured at HV=0 in all gaps with Thr=8.5 fC and with Thr=12 fC in all channels. The thresholds were set individually for each channel according to the relation:
Thr(reg.units)= Thr(fC)*S(reg.un/fC)-OFFSet(reg.un)+Thr_Max(reg.un). Here,
Thr_Max is the threshold at Maximum of noise rate;
OFFSet=17 reg.units (corresponding to 40mV);
S=3.40 reg.units/fC is the charge sensitivity (corresponding to Sens=7.5mv/fC accepted for M3R4 chambers);


HV(ON) HV(OFF)
Chamber HV(A)=2550
GapAB
HV(B)=2550
GapAB
HV(C)=2550
GapCD
HV(D)=2550
GapCD
Thr=8.5 fC Thr=12 fC Atm.Pres. Date Plots Status
50 460.6 458.5 476.5 481.1 3041 .4 Pa=951.3mb 09-FEB-07

Fig.1 Counts distribution over pads in bi-gap AB (odd channels) and in bi-gap CD (even channels) at various HV combinations:
Left_Up: HV(A)=2550V; HV(B,C,D)=0;
Right_Up: HV(B)=2550V; HV(A,C,D)=0;
Left_Down: HV(C)=2550V; HV(A,B,D)=0;
Right_Down: HV(D)=2550V; HV(A,B,C)=0;
Thr=16fC in all channels. Measurements time 100 sec.
Fig.2 Counts distribution over pads in bi-gap AB (odd channels) and bi-gap CD (even channels) at HV=0 in all gaps
Thr=8.5 fC (upper plot) and in Thr=12 fC (down plot) in all channels. Measurements time 1 sec.

<font color="DarkRed" size="6"><i><b>Thresholds Scan. M3R4-50</b></i></font>

Thresholds Scan. M3R4-50

Tables below present:
- Thr_Max(r.u.), Thresholds in register units at Maximum of noise rate;
- N_Max, Noise rate at Thr_Max in counts/sec;
- D_100 = Thr_100(r.u.) - Thr_Max(r.u.) where Thr_100(r.u.) is the threshold in register units at noise rate = 100/s.
The following expression relates the real threshold (measured from the base-line of physical signals) with the thresholds determined by the register units:
Thr(fC)*S(r.u./fC) = Thr(r.u.) - Thr_Max(r.u.)+ OFFSet(r.u.).
Here, OFFSet=17 register units;
S=3.40 r.u./fC is the charge sensitivity corresponding to S=8mV/fC taken for M3R4 chambers;
(Note, that 1 register unit = 2.35 mV)

FEB-1. Mean values. FEB-2. Mean values. FEB-3. Mean values.
Chamber Thr_Max
[r.u.]
N_Max
[counts/s]
D_100
[r.u.]
Thr_Max
[r.u.]
N_Max
[counts/s]
D_100
[r.u.]
Thr_Max
[r.u.]
N_Max
[counts/s]
D_100
[r.u.]
Test Date Plots Comments
50 76 494971 14 83 547228 13 82 538756 13 08-FEB-07 Sens=7.5mV/fc Th=15fc
<font color="DarkRed" size="5"><i><b>Thr_Max in register units for M3R4-50</b></i><br /></font>

Thr_Max in register units for M3R4-50

FEB
Channels
Ch_1 Ch_2 Ch_3 Ch_4 Ch_5 Ch_6 Ch_7 Ch_8 Ch_9 Ch_10 Ch_11 Ch_12 Ch_13 Ch_14 Ch_15 Ch_16
FEB-1 71 73 74 75 82 72 83 66 80 69 81 78 82 81 83 73
FEB-2 88 80 90 82 77 80 84 84 85 86 82 85 82 80 82 75
FEB-3 80 84 78 82 77 87 86 87 81 90 78 85 83 79 72 80
<font color="DarkRed" size="5"><i><b>Noise rate at Thr_Max [counts/sec] for M3R4-50</b></i><br /></font>

Noise rate at Thr_Max [counts/sec] for M3R4-50

FEB
Channels
Ch_1 Ch_2 Ch_3 Ch_4 Ch_5 Ch_6 Ch_7 Ch_8 Ch_9 Ch_10 Ch_11 Ch_12 Ch_13 Ch_14 Ch_15 Ch_16
FEB-1 595461 586125 522105 511396 560133 461471 419555 341291 698706 415390 457524 357602 455353 520636 573172 443611
FEB-2 596418 605703 448079 469052 744755 455090 398505 563194 468396 688902 462575 392017 668780 558032 709728 526423
FEB-3 425416 508356 662202 809598 390026 662114 320023 557536 448926 745319 508890 453649 487232 443912 612231 584658
<font color="DarkRed" size="5"><i><b><FONT FACE="Symbol">D_100 </FONT> - in register units for M3R4-50</b></i><br /></font>

D_100 - in register units for M3R4-50

FEB
Channels
Ch_1 Ch_2 Ch_3 Ch_4 Ch_5 Ch_6 Ch_7 Ch_8 Ch_9 Ch_10 Ch_11 Ch_12 Ch_13 Ch_14 Ch_15 Ch_16
FEB-1 14 12 13 13 15 11 13 12 17 14 15 15 14 13 16 15
FEB-2 12 14 14 14 11 12 11 13 12 14 13 12 14 14 15 14
FEB-3 13 13 12 14 12 13 11 14 11 14 13 12 11 12 14 15
<font color="DarkRed" size="5"><i><b>Noise counts vs Thresholds. M3R4-50</b></i></font>

Noise counts vs Thresholds. M3R4-50


Noise rates vs Thresholds for FEB-1 Noise rates vs Thresholds for FEB-2 Noise rates vs Thresholds for FEB-3
<font color="DarkRed" size="5"><i><b>PLOTS of Thresholds Scan Results. M3R4-50</b></i></font>

PLOTS of Thresholds Scan Results. M3R4-50

Scan results for FEB-1 (left plots), for FEB-2 (middle plots), for FEB-3 (right plots).
Thr_Max vs channel number (upper plot)
N_Max vs channel number (middle plot)
D_100 vs channel number (lower plot)



For comments, contact: Petr.Neustroev@cern.ch