IAC 1-8-08

Signal Cables

HV settings
Cable #	Volts	Desc
223A10		Metalica Sense Wire #4
223A11		Plsstica Sense Wire #4
223A12	1105	PMT Scintillator
223A13	1110	Middle Scintillator
223A14	1090	Last Scintillator (Veto)
223A15		V260 Scaler Input
223A16		V260 Scaler Input

Drift Chamber

90/10 ArCo2

Drift Chamber HV

HV settings
Cable #	Volts	Current (ma)
Sense	1456
Field	729
Guard	731

ADC Channel ID

ADC Channel IDs
ADC Channel	Desc	Patch Panel Channel
0	Metalica wire 1	1
1	Plastica wire 1	2
14	Front Scint	15
15	Back Scint	16
16	Veto Scint	ribbon cable

ADC Peaks (RMS) -- Summary
Run	ADC1	ADC2	ADC15	ADC16
300	344 (21)	252 (34 -- dbl pk)	ped	ped
301	346 (18)	290 (17)	ped	ped
302	441 (8) + ped	253(8) + ped	ped	ped
303	ped	dbl-pk ped ?	ped	ped
304	broad ped	broad ped	ped	ped
305	narrow ped	broad ped	ped	ped
306	few evts at 586 + ped	few evts at 462 + ped	dbl-pk ped	ped
307	narrow ped	broad ped - 65	ped	ped
308	narrow ped	broad ped - 120	ped	ped
309 - 317	ped	ped	ped	ped

Efficiency for Metallika and Plastika as a function of distance from endplate

ADC Peaks (RMS) M/P: > 150 && < 750 (nonpedestal regime)
Run	Entries (number in nonpedestal regime)	ADC1	ADC11	ADC13	ADC2	ADC 12	ADC14	Comments
318	2697 (M: 2690 -- P: 2639)	371 (60)	322 (94))	402 (55)	239 (45)	248 (44)	239 (41)	dbl pk for Metallika z = 10 mm
320	3024 (M: 3018 -- P: 2980)	404 (36)	395 (38)	411 (38)	253 (41)	254 (44)	252 (42)	narrow z = 8 mm
322	3032 (M: 3010 -- P: 2970)	408 (43)	400 (42)	410 (41)	248 (37)	252 (43)	252 (42)	z = 6 mm
323	10032 (M: 10000 -- P: 9875	384 (43)	388 (42)	396 (41)	245 (41)	250 (42)	248 (42)	z = 4 mm
324	7968 (M:6130 -- P: 6085)	383 (42)	385 (39)	390 (46)	245 (45)	249 (43)	248 (43)	Lots of pedestal for both z = 2 mm
326 --> 332 junk or just pedestal

Run 297:

First measurement with ADCs. Zero position (beam hitting trumpet).

Run 298:

Move Drift chamber 1 cm (-20,000 on axis 2, 0.4 [inches] left arrow on GUI) away from trumpet.

We had no PMT coincidences (OR was on).

This run should be ignored because table position meter ("Axis-3" MC 2000) was on and that caused noise on PMT signals.

Run 300.

gate width: 600ns.  PMT gains too low.  Timing is around 100 ns out of time. Plastica and Metalica look good.  

Run 301

Increase gate width to 1 us. PMTs still in the ADCs, but gains are too low. Longer gate width allows for complete integration of the wirechamber ADCs. Signals are better. Position at 1cm from trumpet of feedthrough. 2376 evts.

Front scint 1160
Middle scint 1100

=Run 302

Front scint 1220, Disc threshold 200 mV (Big paddle)
Middle scint 1175, Disc Threshold 51 mV rate is around 1 Hz.

Run 303

Increase current to 15 Hz

FastClear IN

Run 304

Increase current to 15 Hz

FastClear OUT

Run 305

Increase current to 15 Hz

FastClear In

Moved FastClear to 20 us from gate.

Run 307

Everything ORed. Singles. Something wrong with the ADCs. Swap cables to ADC 7 and 8 (plastica and metalica)

Run 308

Plastica SW3 --> Ch. 7 (ADC6) Metalica SW4 Ch. 6 (ADC5) Plastica SW4 --> Ch. 8 (ADC7)

FastClear OUT.

Run 309

Metalica SW4: Ch. 7 (ADC 6)

Plastica SW4 Ch. 8 (ADC 7)

Has stuff in Chan. 8 and 7. Singles (ORed).

FastClear OUT

Run 310

FastClear IN.

Nothing

Run 311

Swap polarity of FastClear. Singles.

Run 312

FastClear IN. Coincidences.

Stuff in Ch. 9 nothing in Ch. 8. nothing in Ch. 7

Run 313

gate width 600 ns FC in

Run 314

FC out

Run 315

HV: SW: +1500V GW: +750V, FW: -750V

Run 315

HV: SW: +1500V GW: +750V, FW: -750V

HV: SW: +1550V GW: +775V, FW: -775V No change in Ch 9. It does not change anything in the ADC.

HV: SW: +1500V GW: +750V, FW: -750V

Run 317

Not gated right. Wchmbr pulses now in gate.

Run 318

sw 4 + 10mm (319 junk)

Run 320

sw 4 +8mm.

Run 321 junk

Run 322

sw 4 +6mm.

Run 323

sw 4 +4mm.

Run 324

sw 4 +2mm.

Run 326

shift in 1 mm.

sw 4 +3mm.

ZEROED.

Run 327

sw4: 0 mm

Run 328

sw4: +1 mm

Run 329

sw4: +2 mm

Run 330

sw4: +3 mm

Run 331

sw4: +4 mm

Run 332

sw4: +10 mm

Run 333

sw4: +30 mm

Run 334

sw4: +50 mm HV: SW: +1500V GW: +750V, FW: -750V

Achtung: Post experiment stuff

Pulse generator problem. What exactly did we trigger on? Was there a shift in the pulse that was sent to us wrt the gun pulse for generating the ADC (integration) gate? We saw a shifting in the gate. We need to systematically study if there is a shift. Note that things went to hell after run 301. We did not change anything except for the width of the gate from 600 ns to 1000 ns. By increasing the width of the gate we increased the integration time and the ADC peak from PLASTIKA went from two peaks (around channel 200) to a nice gaussianlike peak right at channel 500. [Check this]. At run 301 we had the scintillators in the gate, albeit with rather low gain. We then increased the voltages and adjusted thresholds accordingly. Then mysteriously the scintillators fell outside the gate and we had no ADCs from the scintillators. [Were the operators shifting the beam tune to maximize response from the scintillators?]

The peak then magically came back on run 318 and vanished after run 324. In the best case scenario we have 5 good data points: (1.0, 0.8, 0.6, 0.4, and 0.2 mm).

We know the shift was not due to slop in the translation table. The position at the end of the run 334 was +50 mm. We returned to the zero point shifting the 2-axis by 2.0 units in the GUI (2.0 in).

We need belly buttons, lemo cables, connectors: lemo/BNC. Lots and lots of cables.

We need cleaner and smaller scintillators. Nice undergrad project.

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