HRRL 4-13-09

Default HRRL running Conditions

[math]I_{peak}[/math]	Pulse Width	Rep Rate	Energy
8 mA	25 ns	1 Hz	3 MeV

run plan

Date	Task
4/11/09	Vaho stil running til 7 pm, configure Motion Sliders
4/12/09	Build shutter and unstack beam line
4/13/09	Install Aluminum brick shutter and interlock with HRRL, test beam transport: Run HRRL accelerator from 3pm til 5 pm (25 ns pulse width, 3 MeV electrons, 1 Hz rep rate, 8 mA peak)
4/14/09	Repair Freon leak in Chiller, HRRL down, Install DAQ
4/15/09	Run HRRL from 3 pm til 5 pm (25 ns pulse width, 3 MeV electrons, 1 Hz rep rate, 8 mA peak), Do Plateau measurements and test readout
4/16/09	Run HRRL from 9 am til 5 pm (25 ns pulse width, 3 MeV electrons, 1 Hz rep rate, 8 mA peak), Do Plateau measurements and test readout
4/17/09	Run HRRL from 2 pm til 5 pm, position studies using Drift chamber and GEM
4/20/09	Run HRRL from 9 am til 5 pm finish detector tracking studies

4/13/09

Electron Dose tests

Shutter In

0.1 mrad/hr outside HRRL experimental door.

2.7 mrad/hr in the end of HRRL experimental hallway.

Shutter Out

0.1 mrad/hr in Dr. Forest office.

Sintillator tests

RS1 = 2 aluminum blocks are in front of Long BLue Scintillator plugged into the cable patch panel 223A2

FS2 = Small scintillator is in 223A1

FS1 = Front Long Blue Scintillator plugged into the 223A4 and High Voltage - A3 channel.

HV SC1	HV RS1	Desc.
840	840

GEM noise

100 ns RF pulse width

GEM in Accelerator room

Bag	Rep Rate	Beam Current	Peak to peak noise
Off No ground strap	990 Hz	3 V =60 mA	[math]29 \pm 2[/math] mV on 1 mus scale
Off + ground strap	990 Hz	3 V =60 mA	[math] 72\pm 1[/math] mV on 1 mus scale
on No Ground strap	990 Hz	4 V =80 mA	[math] 42 \pm 2[/math] mV on 1 mus scale
on + Ground strap	990 Hz	3 V =60 mA	[math]66 \pm 2[/math] mV on 1 mus scale
on + Ground strap + insulation	990 Hz	3 V =60 mA	[math] 52\pm 30[/math] mV on 1 mus scale

The insulation was placed between the mylar bag and the BNC conenctor on the HV board. The inside of the mylar bag is conducting. There is a film covering the outside of the mylar bag which prevents conduction test with voltmeter.

GEM in HRRL exp cell

Bag	Rep Rate	Current	Peak to peak noise
Off No ground strap	990 Hz	3 V =60 mA	[math] 46\pm [/math]1 mV on 1 mus scale
on + Ground strap + insulation	990 Hz	3 V =60 mA	[math] 52 \pm 16[/math] mV on 1 [math]\mu[/math]s scale

The insulation was placed between the mylar bag and the BNC conenctor on the HV board. The inside of the mylar bag is conducting. There is a film covering the outside of the mylar bag which prevents conduction test with voltmeter.

4/16/09

The Plateau Measurements were done using Aluminum Brick. A 2X4X8 Aluminum brick shutter stopped 3 MeV electrons from entering the HRRL experimental cell. The rates seen by the DC and front scintillator were compared when the brick was in vs out. Plateau Curve shown below is based on the data which is represented in this section for each DC Sense High Voltage. The DC Sense HV range was chosen from 1200 Volts to 1550 Volts. For each voltage the data was taken two or three times. It looks like the rate is not changing much in region of the DC Sense HV ~1250-1500 Volts. Below 1200 Volts of DC Sense i was not getting any events. So i decided to stop At 1200 Volts and not go below that.

[math]Rate % \equiv \left ( \left [\frac{\mbox{Counts(DCSenseWire4 + Front Scint + RF)}}{\mbox{RF Pulses}} \right ]_{\mbox{BrickOut}} - \left [\frac{\mbox{Counts(DCSenseWire4 + Front Scint + RF)}}{\mbox{RF pulses}}\right ]_{\mbox{BrickIn}}\right ) \times 100 %[/math]

add to data table and figures the individual brick out/in rate measurements

Data Table

DC Sense HV (Volts)	Rate % (BrickOut-BrickIn)
1200	0.11 [math]\pm[/math] 0.008
1300	2.07 [math]\pm[/math] 0.18
1400	9.25 [math]\pm[/math] 1.35
1500	11.3 [math]\pm[/math] 3.4
1550	32.57 [math]\pm[/math] 0.46

Our Plateau Curve

Plateau Curve

DC + FSC1 Coinc

Accelerator Rep rate is 100 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	16990	1568	9.2 %
In	54801	310	0.6%
Out	10242	841	8.2%
In	17945	93	0.5 %
Out	20871	1791	8.6%
In	15101	71	0.47 %
Out	6549	531	8.1%

It looks like we have electrons firing the DC 10% of the time and photons less than 1% of the time.

HV Settings S:F:G=1800:-900:1260

Accelerator Rep rate is 900 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	1820	285	15.6 %
In	6048	161	2.7 %
Out	1420	219	15.4%
In	3230	110	3.4 %

HV Settings S:F:G=1750:-875:1225

Accelerator Rep rate is 900 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	2022	213	10.5%
In	37277	308	0.8 %
Out	1502	178	%
In	12152	112	%
Out	2325	287	%
In	35474	368	%

HV Settings S:F:G=1700:-850:1190

Accelerator Rep rate is 900 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	2358	428	18 %
In	6576	123	1.9 %
Out	3115	531	17 %
In	86819	1278	1.5 %

HV Settings S:F:G=1650:-825:1155

Accelerator Rep rate is 900 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	2690	679	25 %
In	3560	119	3.3 %

HV Settings S:F:G=1600:-800:1120

Accelerator Rep rate is 900 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	3428	1010	29 %
In	3904	120	3%

HV Settings S:F:G=1550:-775:1085

Accelerator Rep rate is 900 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	2690	982	36.5 %
In	2352	105	4.4 %
Out	645	240	37%
In	61988	2878	4.6 %
Out	2391	927	38%
In	2872	139	4.8%

HV Settings S:F:G=1500:-750:1050

Accelerator Rep rate is 900 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	8021	1442	17 %
In	37506	884	2.3 %
Out	5428	1431	8.2%
In	4496	116	0.3 %

HV Settings S:F:G=1400:-700:980

Accelerator Rep rate is 900 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	50815	5703	11 %
In	41621	178	0.4 %
Out	70392	8274	8.2%
In	34700	120	0.3 %
Out	9835	1278	13 %
In	44456	102	0.2%

HV Settings S:F:G=1300:-650:910

Accelerator Rep rate is 900 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	38108	1016	2.66 %
In	48996	190	0.38 %
Out	23693	532	2.24%
In	71868	103	0.14 %
Out	86296	1693	1.96%
In	124099	147	0.118 %

HV Settings S:F:G=1200:-600:840

Accelerator Rep rate is 900 Hz

Brick	Gun Pulses	DC pulses	DC/Gun pulses
Out	63976	141	0.2 %
In	108886	97	0.09 %

ADC Measurements

1300 r936 14:41:51 14:49:18 BreakOut

1400 r937 14:50:40 14:51:14 BreakOut

1500 r938 14:54:30 14:55:44 BOut

1600 r939 14:57:10 14:58:47 Bout

1700 r940 15:00:39 15:04:47 bO

1800 r942 15:12:26 15:15:46 bo

1350 r946 15:25:24 15:26:39

1450 r948 15:31:29 15:32:05

1550 r943 15:17:40 15:19:19

1650 r944 15:20:08 15:21:00

1750 r945 15:21:40 15:22:49

Position Measurement

break Out

HV 1450 Sense Wire

on edge of the drift chamber r949 15:48:06 15:48:50

Drift Chamber is removed from the beam r950 15:51:39 15:55:41

Beam is at the center of DC r951 15:59:45 16:00:12

(from Center) 2" r952 16:06:20 16:06:54

4" r953 16:07:54 16:08:08

6" r954 16:09:01 16:09:16

The histograms below are weighted by time, y axis reprezent number of counts per second.

4/17/09

Started at 2:25 pm

 where are the log book entries for today?

Screen

100 mA no electrons on the screen, the highest current.

At 1850 Volts on sense DC starts sparking on lowest Beam current.

4/20/09

Trigger setup

As a trigger 3 Scintillators with RF Gate were used. Drift Chamber was sandwiched between the 1cm^2 Small fron PMT and Blue Second scintillator. At the end we had also blue scintillator. Two Blue scintillators were forming cross.

500px

Run Range

Determine range of operating conditions for DC HV, rep rate and beam current

Run #	Brick In/Out	rep rate (Hz)	current (ma)	Number RF gates (SCAL13)	Number Coincidences (SCAL08)	DC singles	FC spectrum	DC spectrum	comments
999	Out	65	40
1000	Out	900	40					100px

Looks like we should run at 40 mA peak current and change the DC HV from 1200 to 1600 Volts on the sense wire

Plateau Measurements

Run #	Brick In/Out	rep rate (Hz)	current (ma)	DC HV (S:F:G)	Number RF gates (SCAL13)	Number Coincidences (SCAL08)	DC coinc with 3PMT + RF gate (SCAL02)	Rate SCAL02/SCAL13 (%)	FC spectrum	DC spectrum	DC spectrum(CUT on ADC>80, log scale) Events/sec	comments
1003	Out	65	40	1600::	109632	217476	28709	26.2		100px 100px		Overflows in DC ADC spectrum
1006	Out	900	40	1600	115719	212130	37534	32.4
1007	Out	900	40	1550	5781	2427	1751	30.3			100px
1008	Out	900	40	1550	5803	2399	1832	32				2dB attenuation added
1009	Out	900	40	1500	5650	2376	1705	30.2			100px
1010	Out	900	40	1500							100px
1012	Out	900	40	1500	4589	1842	1385	30.2				5dB attenuation added
1014	Out	900	40	1450	6285	2609	1875	30
1015	Out	900	40	1400	6089	2501	1743	28.6
1016	Out	900	40	1350	9398	3799	998	10.6
1017	Out	900	40	1300	6567	2681	1167	17.7
1018	Out	900	40	1250	5440	2278	694	12.7
1019	Out	900	40	1200	4123	1738	619	15
1020	out	900	40	1150	4402	1798	790	17
1021	out	900	40	1425	5521	2280	1812	32
1022	in	900	40	1425	4681	1531	825	17.6
1023	in	900	40	1600	3748	1155	739	19			100px
1024	in	900	40	1550	6156	1899	1172	19			100px
1025	in	900	40	1500	6280	1920	1230	19			100px
1026	in	900	40	1450	3631	1142	799	22			100px
1042	in	900	40	1300	3616	1167	424	11.7
1043	in	900	40	1350	3453	1094	441	13
1044	in	900	40	1250	3719	1262	598	16
1045	in	900	40	1200	3270	1004	342	10
1046	in	900	40	1150	2731	911	282	10

At 1350 Volts HV of Sense wire the count rate seemed like dropped, so i did scaler measurements again twice when the brick was out, and i got the following result: 27 % instead of 10 %. (2867 - 1116 - 776) .

Position measurements

Scaler Measurements

Data Summery Table

Distance from the Endplate of DCSenseWire4 (inches)	Rate %	Error %
1"	12	0.53
2"	12	0.52
3"	15	0.5
4"	14	0.48
6"	15	0.5
7.5 "	18	0.51
DC removed from beam	0.6	2.88

Run #	Brick In/Out	rep rate (Hz)	current (ma)	Distance from the Endplate of DCSenseWire4 (inches)	Number RF gates (SCAL13)	Number Coincidences (SCAL08)	DC coinc with 3PMT + RF gate (SCAL02)	Rate SCAL02/SCAL13 (%)
1028	Out	900	65	1"	3561	1462	819	22
1029	Out	900	65	2"	9988	4012	2480	25
1030	Out	900	65	3"	4738	1943	1217	25
1031	Out	900	65	4"	4683	1891	1214	26
1032	Out	900	65	6"	2440	1001	619	26
1033	Out	900	65	7.5"	3420	1414	965	28
1041	Out	900	65	DC is removed from the beam	4570	1843	41	0.9
1039	In	900	65	1"	4074	1342	388	10
1039	In	900	65	2"	5242	1681	554	10
1039	In	900	65	3"	2366	755	261	11
1039	In	900	65	4"	2437	821	287	12
1039	In	900	65	6"	2926	904	320	11
1039	In	900	65	7.5"	3948	1247	408	10
1040	In	900	65	DC is removed from the beam	5516	1780	18	0.3

Go Back Qweak