<i>Test Results for Chamber M3R4-68</i></font>

Test Results for Chamber M3R4-68


<font color="#00008B" size="5"><i><b>Bar Codes Table. M3R4-68</b></i></font>

Bar Codes Table. M3R4-68

Chamber
M3R4
Chamber
Bar Code
FEBs
Bar Codes
Date Dressing Comments
68 4UAPNB03400068 4UE20900112519
4UE20900112349
4UE20900112264
06-MAR-07 Chamber is in the Pit


<font color="DarkBlue" size="5"><i><b>Gas Leak Test. M3R4-68</b></i></font>

Gas Leak Test. M3R4-68

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

Limit: <= 2mb/hour

Chamber Gas Leak
[mb/hour]
Test Date Comments
68 .1 Relative methode


<font color="DarkBlue" size="5"><i><b>Durk Current Test. M3R4-68</b></i></font>

Durk Current Test. M3R4-68

<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
68 0 0 0 2 4 10 06-OCT-05 chamber is OK



<font color="#00008B" size="5"><i><b>Cosmic HV-Test. M3R4-68</b></i></font>

Cosmic HV-Test. M3R4-68

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
68 1
2
270
271
334
323
344
344
382
392
530
581
909
982
10-MAR-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. M3R4-68</b></i></font>

Cosmic Rays and Noise Counts from Internal Counters. M3R4-68

Table presents counting rates (counts per 100 sec) averaged over 24 pads in bi-gap AB or in bi-gap CD measured with Thr=12fC 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=8.5fC and with Thr=10fC 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 Thr=16fc 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=8.5fC Thr=10fC Atm.Pres. Date Plots Status
68 450.4 473.1 467.3 436 1952.1 86.3 Sens=7.5mv/fC 08-MAR-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=12fC 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=8.5fC (upper plot) and in Thr=10fC (down plot) in all channels. Measurements time 1 sec.

<font color="DarkRed" size="6"><i><b>Thresholds Scan. M3R4-68</b></i></font>

Thresholds Scan. M3R4-68

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
68 81 444098 14 81 411930 12 76 475820 12 08-MAR-07
<font color="DarkRed" size="5"><i><b>Thr_Max in register units for M3R4-68</b></i><br /></font>

Thr_Max in register units for M3R4-68

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 78 80 83 92 79 81 78 89 69 83 79 86 80 87 82 76
FEB-2 78 91 83 74 81 77 79 81 88 78 81 87 78 79 84 81
FEB-3 71 78 77 76 69 73 73 72 76 72 78 74 84 74 85 84
<font color="DarkRed" size="5"><i><b>Noise rate at Thr_Max [counts/sec] for M3R4-68</b></i><br /></font>

Noise rate at Thr_Max [counts/sec] for M3R4-68

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 488186 429558 740920 269666 691540 458986 349463 240867 397057 418893 497941 235437 501088 340944 438338 606680
FEB-2 496206 430646 334683 445366 364069 288192 347740 309740 389009 290822 413983 304317 521242 331160 594070 729642
FEB-3 498768 433702 426899 465423 541265 438088 445334 386222 386602 340655 560449 328555 723837 397565 564440 675317
<font color="DarkRed" size="5"><i><b><FONT FACE="Symbol">D_100 </FONT> - in register units for M3R4-68</b></i><br /></font>

D_100 - in register units for M3R4-68

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 13 14 13 17 13 15 14 15 14 16 13 14 14 13 13
FEB-2 13 12 12 12 11 11 11 10 11 12 11 12 13 11 13 13
FEB-3 13 13 12 13 12 10 12 10 12 11 11 12 13 12 14 13
<font color="DarkRed" size="5"><i><b>Noise counts vs Thresholds. M3R4-68</b></i></font>

Noise counts vs Thresholds. M3R4-68


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. M3R4-68</b></i></font>

PLOTS of Thresholds Scan Results. M3R4-68

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