On 25/11/2018:

The beam was tuned for 6.0MeV 7Be 2+

Using 10mm aperture FCC = 12 pA

Run # 181125121226

• Run time: 7264s
• Pulser ON, as before
• Target: CH2 XVIII
• Beam: 6.0MeV 7Be 2+
• See attached picture 1 for sample spectrum of Far S2 front strip. See attached picture 2 for diode spectrum.

Run # 181125141350

• Run time: 1887s
• Pulser ON, as before
• Target: CH2 XVIII
• Beam: 6.0MeV 7Be 2+

During this run at 14:40 there was a very brief power outage. The run was stopped afterwards.

Check chamber setup:

Far S2 bias = -130.0V, leak I = 1.89uA

Diode bias = -70.1V, leak I = 0.00uA

Pressures (mBar):

• TPU1 = 1.0e-6
• TPU2 = 3.2e-7
• TPD1 = 6.5e-7
• TPD2 = 6.1e-7
• CHUP = Sensor Off
• CHDW = No Sensor

Preamps for Far S2 and diode are still drawing correct currents. The chamber setup appears unaffected by the brief outage.

At this point the pulser was disconnected from the oscilloscope - removing the load on the pulser. We expect the pulser peak position to change as a result.

After the outage we needed to retune beam for 6.0MeV 7Be 2+

Moved target ladder to position #2 - blank 10mm aperture. Had troubles finding beam, moved target to natC III. In diode spectrum we saw beam energies ~ 7-8MeV.

It turned out the bending magnet located right after the ion splutter source needed recalibrating. It was recalibrated using Hydrogen (A=1), Carbon (A=12), and Oxygen (A=16).

During the retuning, the pulser frequency was checked for both the 2.5 and 25Hz settings:

Pulser setting set to 2.5Hz

• Pulser frequency measured internally by scope: 2.095 -> 2.096Hz
• Pulser frequency measured using scopes cursors: 2.092Hz

Pulser setting set back to 25Hz

• Pulser frequency measured internally by scope: 19.29 -> 19.30Hz
• Pulser frequency measured using scopes cursors: 19.38Hz

After recalibrating the bending magnet, we switched beam to 6.0MeV 7Li 2+ to benefit from the higher beam current.

After tuning: FC4 = 1.25nA. Using blank 10mm aperture FCC = 96pA, using blank 3mm aperture FCC = 66pA -> ~70% transmission attained.

Switched beam back to 6.0MeV 7Be 2+

Using 3mm aperture FCC = 7pA.

Opened Far S2 iris (was closed during retuning after power outage), set target ladder to CH2 XVIII

Run # 181125223800

• Run time: 35914s
• Pulser ON, 25Hz
• Target: CH2 XVIII
• Beam: 6.0MeV 7Be 2+
• Left running overnight
• See attached picture 3 for sample spectrum of Far S2 front strip. See attached picture 4 for diode spectrum.

On 25/11/2018:

At 8:45 the pressures read (mBar):

• TPU1 = 1.0e-6
• TPU2 = 3.2e-7
• TPD1 = 6.5e-7
• TPD2 = 6.1e-7
• CHUP = Sensor Off
• CHDW = No Sensor

Biased detectors: Far S2 bias = -130.0V, leak I = 1.80uA. Diode bias = -70.1V, leak I = 0.00uA.

Checked pulser frequency:

• Frequency setting = 25Hz (250Hz max fine gain setting)
• Pulser frequency measured internally by scope: 19.29->19.31Hz
• Pulser frequency measured using cursors on scope: 19.38Hz

Target ladder left in position #2 overnight - 10mm aperture. Far S2 iris also left open overnight.

Checked for beam induced background from beam scattering on aluminium target frame and/or ladder. FC4 ~ 17pA, FCC ~ 6pA

Run # 181125090005

• Run time: 977s
• Pulser ON, as before
• Target: 10mm aperture
• Beam: 4.0MeV 7Be 2+

Tuned beam for 6.0MeV 7Li 2+

After tuning: FC4 = 1.05nA. Using 10mm aperture FCC = 520pA, using 3mm aperture FCC = 460-480pA.

Collected 7Li + p data using old target CH2 XVI (used for 7Be yesterday)

Run # 181125112005

• Run time: 754s
• Pulser ON, as before
• Target: CH2 XVI
• Beam: 6.0MeV 7Li 2+
• DT ~ 10%

Run # 181125113257

• Run time: 18s
• Pulser ON, as before
• Target: CH2 XVI
• Beam: 6.0MeV 7Li 2+

Moved target ladder to position # 4 - fresh CH2 XVIII

Run # 181125113734

• Run time: 324s
• Pulser ON, as before
• Target: CH2 XVIII
• Beam: 6.0MeV 7Li 2+

See attached picture 1 for a sample spectrum from one of the Far S2 front strips. See attached picture 2 for the diode spectrum.

Moved target ladder to position #5 - natC III

Run # 181125114513

• Run time: 620s
• Pulser ON, as before
• Target: natC III
• Beam: 6.0MeV 7Li 2+

After the previous run, it was discovered the pulser was still being split between the far S2 preamp test input, and the oscilloscope (morning check of pulser frequency). Therefore the pulser had an additional load and we expect a shift in the pulser amplitude compared to runs made yesterday.

Checking for beam induced background, the target ladder was moved to position #2 - blank 10mm aperture

Run # 181125115810

• Run time: 386s
• Pulser ON, as before
• Target: Blank 10mm aluminium frame
• DT ~ 8%
• FCC ~ 400pA

On 24/11/2018:

After the short test with 4.0MeV 7Li (see eLog #55) the beam was tuned for 4.0MeV 7Be 2+.

Run # 181124103943

• Run time: 43s
• Target: CH2 XVI
• Beam: 4.0MeV 7Be 2+
• Comment: Far S2 iris was closed!

Run # 181124104408

• Run time: 3971s
• Pulser ON, as before
• Target: CH2 XVI
• Beam: 4.0MeV 7Be 2+

After this run we checked the beam current:

FC4 = 10pA

Using 10mm aperture FCC = 4.5pA, using 3mm aperture FCC = 4.0pA

Attempted to increase beam current by adjusting bending magnet - optimum: 413.30mT

Run # 181124120558

• Run time 7930s
• Pulser ON, as before
• Target: CH2 XVI
• Beam: 4.0MeV 7Be 2+

See attached picture 1 for a sample spectrum from the S2 front strip. See attached picture 2 for the diode spectrum - the peaks from 7Be and 7Li are visible. Recall the diode has a 0.9um mylar protective foil in front of it.

Run # 181124141834

• Run time: 3362s
• Pulser ON, as before
• Target: CH2 XVI
• Beam: 4.0MeV 7Be 2+

Further attempts to increase beam current, ioniser increased from 24.0 -> 24.5A. FC4 = 15pA

Run # 181124154345

• Run time: 3609s
• Pulser ON, as before
• Target: CH2 XVI
• Beam: 4.0MeV 7Be 2+

Checked beam current: using 10mm aperture FCC = 4pA (time: 16:44)

Decreased oven temperature -> FC4 = 16pA

Run # 181124165221

• Run time: 4221s
• Pulser ON, as before
• Target: CH2 XVI
• Beam: 4.0MeV 7Be 2+

Collected background using carbon target:

Run # 181124180623

• Run time: 463s
• Pulser ON, as before
• Target: natC III
• Beam: 4.0MeV 7Be 2+

Beam current seemed unstable, run stopped, no actions taken. FCC ~ 5pA.

Run # 181124182304

• Run time: 3647s
• Pulser ON, as before
• Target: natC III
• Beam: 4.0MeV 7Be 2+

See attached picture 3 for a sample spectrum from the S2 front strip. The spectrum indicates hydrogen contamination is present on the carbon foil. See attached picture 4 for the diode spectrum.

After run: checked beam current. FC4 = 18pA. Using 10mm aperture FCC = 5.5pA.

Leaving for the night:

Far S2 leak I = 1.87uA. Far S2 and diode biases off.

19:25 pressures (mBar):

• TPU1 = 1.4e-6
• TPU2 = 3.7e-7
• TPD1 = 7.0e-7
• TPD2 = 6.6e-7
• CHUP = Sensor Off
• CHDW = No Sensor

On 24/11/2018:

At 8:35 the chamber pressures read (mBar):

• TPU1 = 2.2
• TPU2 = 2.2
• TPD1 = 2.2
• TPD2 = 2.0
• CHUP = Sensor Off
• CHDW = No Sensor

The chamber was vented and the CH2 XV target replaced with new ones.

See picture 1 for target ladder after dismounting - the beam spot from 7Li is clearly visible on CH2 XV.

The target ladder configuration is now:

See picture 2 for the new configuration.

The target ladder was remounted and at 9:15 the chamber pumped down. The far S2 still has the 12um mylar protective foil.

By 9:30 the pressures read (mBar):

• TPU1 = 4.6e-5
• TPU2 = 7.4e-6
• TPD1 = 6.8e-6
• TPD2 = 8.7e-6
• CHUP = Sensor Off
• CHDW = No Sensor

The Far S2 was biased to -130V, leak I = 1.38 uA. The diode biased to -70V, leak I = 0.00uA

A beam of 7Li 2+ 4.0MeV was focused onto the target position.

After focussing, FC4 = 260 pA, FCA = 250 pA. Both of these faraday cups are before the target chamber.

After focussing with the 10mm aperture, FCC = 195 pA. Focussing with the 3mm aperture, FCC = 190 pA. Faraday cup C (FCC) is after the target chamber.

A spectrum was collected for 7Li 4.0MeV

Run # 181124101041

• Run time: 717s
• Pulser ON, 25 Hz, as before
• Target: CH2 XVI
• Beam: 4.0 MeV 7Li 2+
• Trigger rate: 3285/s
• DT ~ 6%

On 23/11/2018:

After the runs with 7Li on CH2 15, we moved the target ladder to position 5: carbon foil #3 (~590 ug/cm^2)

Run # 181123214406

• Run time: 1247
• Pulser ON, same settings as run # 181123130304

Beam intensity = 150pA on FCC with 3mm aperture

For the night we closed the quadrupole and line valves, and switched off the pumps and detectors.

On 23/11/2018:

Tuned beam for 4.0 MeV 7Li, charge state 2+

Measured transmission of beam through FCC using 3 mm and 10 mm size collimators: 66 pA with 10 mm -> 60 pA with 3 mm -> 91% transmission

FC4 = (330 - 263) pA = 127 pA

Set target ladder to position 3 - CH2 target 15 (880 +/- 40 ug/cm^2)

Start run

• Run # 181123130304
• Pulser: 70000 amplitude, x10 attenuation, 25Hz frequency (250Hz minimum fine setting), positive polarity
• Run time ~30 minutes

Start run

• Run # 181123134943
• Pulser: as above
• Run time 588 seconds

Moved to position #2 on target ladder, 10mm collimator. Increasing beam intensity -> have to refocus

Moved ladder to position #1 (3mm collimator). Closed iris. Refocusing.

Beam intensity after refocus: ~140pA with 10mm, ~90pA with 3mm. Trigger rate ~ 5500 counts/s

Moved ladder to position #3: CH2 target 15

Run # 181123142805

• Pulser: as above
• Run time: 1034

We found high rates on ADC 1 -> swapped input cables between ADC 1 and ADC 2 (modules #2 and #3)

Run # 181123144810

• Run time: 417
• Pulser: as above

Set RAL thresholds to 20mV for first 8 modules

Run # 181123150803

• Run time: 398
• Pulser: as above

Did not help with ADC 1 counting less than ADC 2. Swapping ADC 1 with ADC 4.

Run # 181123151711

• Run time: 324
• Pulser: as above

Swapping back ADC 4 -> ADC 1. Found ECL cable between the MALU module corresponding to ADC 1 and OR not plugged in. Trigger rate now 44000. Re-optimising noise.

RAL first 6 modules thresholds set to 30 mV. DT ~ 44%, high trigger rate.

First 3 RAL thresholds set to 35 mV, next 3 RAL thresholds set to 20 mV. Preamp box lid removed.

Run # 181123162236

• Run time: 348
• Pulser OFF

Run # 181123163138

• Run time: 1561
• Pulser: ON, rate: 2.5 Hz, other settings unchanged

Run # 181123165817

• Run time: 3731
• Pulser as previous run

Run # 181123180118

• Run time: 1971
• Pulser ON, as before

Run # 181123183556

• Run time: 1638
• Pulser ON, as before

Checking beam intensity:

• Beam intensity = 197pA in FC4 at 18:34
• Beam intensity = 100 pA (91->105 pA) in FCC at 19:00

Run # 181123191153

• Run time: 7029
• Pulser ON, as before

Checking beam intensity:

• Beam current = 167 pA in FC4 at 21:00
• Beam current = 83 pA in FCC at 21:00

Lowering RAL thresholds:

• RAL #1 and 2 thresholds set to 25mV
• RAL #3 threshold set to 20mV
• RAL #4, 5, and 6 thresholds unchanged at 20mV

Now trigger rate ~ 5kHz, dead time ~ 8 - 10%

Run # 181123212726

• Run time: 807
• Pulser ON, as before
• Target: CH2 XV
• RAL #3 threshold increased to 25mV during this run

After previous run (# 181123212726) pulser frequency setting set to 25Hz, other settings unchanged

On 23/11/2018:

10:15 started pumping down chamber with Ecodry 2

RAL thresholds:

• First 4 RALs = 10mV
• 5th RAL = 17mV
• 6th RAL = 20mV
• 7th and 8th RALs ECL disconnected
• 9th - 16th RALs not in use (no near S2)

10:30 pressures ~ 1mBar, opened T1600 backing valve, Turbos switched on

10:35 pressures (mBar):

• TPU1 = 5.2e-5
• TPU2 = 6.4e-6
• TPD1 = 6.0e-6
• TPD2 = 8.7e-6
• CHUP = 2.3e-5
• CHDW = 5.5e-5

Biased detectors: Far S2 bias = -130V, leak I = 1.54uA. Diode bias = -70V, leak I = 0.02uA.

Replaced diode TFA, now using channel 4 on new TFA. Diode connected to 3rd ADC channel 16 (counting from 0)

Started pulser only run

• Run # 181123111015

Closed far S2 iris (82.5mm actuator setting). Set target ladder to blank 10mm target frame.

Disconnected vacuum gauges located below chamber on same side as target ladder is mounted - noise improved

Started pulser only run

• Run # 181123113237

On 22/11/2018 in the afternoon:

We increased the ADC thresholds to 40 (previously 8).

For an alpha source with pulser connected, the event multiplicity dropped from ~63 to ~10. Dead time ~ 7%

Checking the timing signals for the near S2:

• RAL X channels 0 - 5 bad, 6 and 7 good -> disconnected timing
• RAL U, XII, XIII, R, and S good
• RAL W channels 0 - 5 good, 6 and 7 bad
• RAL Q all bad -> disconnected timing

Started alpha source run with pulser (same pulser settings as run before)

• Run # 181122161955

After run the Far S2 RAL thresholds set to 10mV, the close S2 thresholds set to 50mV

Started alpha source run, no pulser

• Run # 181122170947

Stopped run due to poor alpha rate -> ECL-Nim ribbon cable disconnected.

Checking bias:

• Far S2 bias = -130V, leak I = 1.91uA
• Close S2 bias = -129.9V, leak I = 13.11uA
• diode bias = -70V, leak I = 0uA

Vented chamber and checked 12um mylar foil in front of close S2 - no visual damage. LEft

Close detector changed: S2 2623-26 (505um) replaced with S2 2623-18 (508um). Mounted new S2 in close position with 12um mylar

Removed alpha source - needed by other experiment. Otherwise target ladder configuration is same as eLog entry #47

Checked grounding cables going from preamps to ICU boxes were tightly connected

Attempted to bias close S2 -> no leak current! Left lab for the day.

The next morning (23/11/2018):

We found the BNC - SMC bulkhead connector attached to the near S2 preamp box is missing a pin. We dismounted the near S2.

We observed ~50kHz noise on Far S2, this is removed when we lifted the preamp - ICU box ribbon cables away from the chamber vacuum gauges.

The FAIR DAQ IP address: 192.168.1.90

The data is saved in /Local_Parts/Part0DE/

After each run we should copy the data to the 7Be shift folder: /home/circe/7Be_pp/181122/

We convert the data to a .root file via the command: fair2root ./run#

To convert the data to root we need to use the fairdef.in config file

The target ladder is set for position 7 - the double alpha source.

Looking at the FAIR DAQ, for the Far S2 the first RAL amplifier (XV) shows:

• Alphas at channel 700
• Pulser centroid at channel ~2640, with 9 channel FWHM -> corresponds to 44 keV FWHM at 4.91 keV/channel

The close S2 shows:

• Alphas at channel 700
• Same pulser centroid as far S2, with 6 channel FWHM -> corrsponds to 24 keV FWHM at 4.91 keV/channel

We reenabled the top ICU box channels 0 and 5 (disabled during Feb 2018 shift)

We started an alpha-source run using the 241Am and 239Pu source, type: EA X, product number: 111109-1242002. Photo of source storage case is attached.

Alpha activity at 25/03/2010: 8.153 kBq

We found the following strange behaviour

With DAQ list mode OFF:

• Trigger rate ~2300 - 2700/s
• Event mult ~ 140
• DT~18%

With DAQ list mode ON:

• Trigger rate ~300 - 900/s
• Event mult ~140
• DT ~ 70 - 90%

Currently ADC 2, 3, 4, and 5 are in use by the far and near S2's. ADC 6 and TDC 7 are not currently in use (we will need ADC 6 for the pin diode)

We set the lower threshold for ADC6 and TDC7 to 2046 out of 2047 channels - effectively disabling the two.

Now with list mode ON:

• Trigger rate ~ 1500 - 1700 /s
• Event mult ~ 65 - 70
• DT ~ 30 - 50 %

We restarted the DAQ machine

We started an alpha source run:

• Run number: 181122123034
• DT ~ 7 - 19%
• Trigger rate ~ 700 - 1000/s
• Event mult ~ 63

The PB-4 Pulser Settings are:

• Frequency: 250 Hz
• Delay: 1 us
• Rise Time: 0.1 us
• Fall Time: 100 us
• Reference: INT
• Polarity: +ve
• Amplitude on scope: 260mV
• Attenuation: X10 (X10 switch up, X2, X5, and the other X10 switch are down)

This morning at 8:35am the pressures read (in mBar):

• TPU1 = 2.0e-6
• TPU2 = 4.5e-7
• TPD1 = 8.1e-7
• TPD2 = 7.9e-7
• CHUP = 4.7e-7
• CHDW = 1.1e-5

The detectors were biased. Far S2 leak I = 1.54uA, near S2 leak I = 12.53uA.

It was discovered the ECL-NIM-ECL converter located immediately to the left of the pulser has broken channels - the last 8 channels. Instead of connecting the 32 pin ribbon cable to the input and taking lemo outputs 5 and 13,  we are now connecting two single channel pin cables to inputs 1 and 2, and taking the corresponding lemo outputs.

We found RAL X sometimes doesn't produce a trigger for the pulser.

We replaced RAL I with RAL XIV, RAL XIV is bad.

We replaced RAL XIV with RAL XV,  RAL XV is good.

We finished setting the RAL thresholds.

Today we mounted the far aperture used to control the far iris. No problems were encountered with this.

We mounted the target ladder with the following configuration, see also pictures 1 and 2:

The alpha source is 241Am + 239Pu

We also have mounted the near and far S2's with 12um mylar, and the pin diode with 0.9um mylar.

We only had the far iris arm actuator mounted, because a new iris arm for the near iris mount was being manufactured in the CIRCE workshop.

During ~midday through the early afternoon we found vacuum problems. These were solved by remounting the far chamber lid, and also remounting the far iris arm actuator (This had incorrect length bolts).

The new iris arm for the near S2 came back from the workshop, unfortunately we still could not mount it. We decided against mounting this iris arm, and instead mount the near S2 with the iris completely open and the 12um mylar protective foil.

We will only be able to measure at Elab = 4MeV, becasue at Elab = 6MeV the 7Li penetrates through 12um mylar and so we would be risking the near S2 during beam tuning (not an option!).

We mounted the near S2 with iris open and 12um mylar foil. The far S2 was already mounted with 12um foil and the iris arm aperture. The far S2 iris was opened fully (setting 1.5mm on actuator) ready for pumping and alpha source measurement.

At 16:50 we started the Ecodry 1 and 2 pumps and opened the manual gate valve. By 16:55 we fully opened the gate valve and also the T1600 backing valve, allowing both ecodrys to pump on the chamber. We then switched on the turbos.

By 17:20 the pressures read (in mBar):

• TPU1 = 3.4e-5
• TPU2 = 3.3e-6
• TPD1 = 3.4e-6
• TPD2 = 4.1e-6
• CHUP = 1.2e-5
• CHDW = 2.8e-5

During pump down we mounted the preamp boxes with daisy chained BNC cables.

We applied preamp power, correct currents drawn: ~1.5A for +ve and ~500mA for -ve

Far S2 biased to -130V, leak I = 1.46uA. Near S2 biased to -130V, leak I = 2.48uA.

Checking for noise, we see the following RMS noise in the RAL amps:

Diode biased to -70V, leak I = 0.02uA

We tested for ground loops - no obvious loops found for either S2 preamp

We connected the RAL amps to the FAIR DAQ, and started an alpha source run with pulser. The dead time was excessively high, ~90%

We started adjusting RAL thresholds up to RAL S, then we called it a day.

The Far S2 leak I = 1.4 uA, near S2 leak I = 3.3 uA.

We unbiased the detectors, switched off the NIM, CAMAC, and RAL crates, and also switched off the preamp power. We didn't wanted anything damaged from potential overnight thunderstorms.

At 20:35 the pressures read (in mBar):

• TPU1 = 6.3e-6
• TPU2 = 8.0e-7
• TPD1 = 1.2e-6
• TPD2 = 1.2e-6
• CHUP = 6.2e-6
• CHDW = 1.4e-5

On 20/11/2018:

After the electronics tests in air (see eLog entry #44) we started to setup the chamber for vacuum tests with an alpha source.

We started mounting the aperture used for controlling the near iris arm, however we encountered a problem. The iris arm got stuck and could not move in either direction (into or out of the chamber)

We dismounted both preamps. After bending the near iris arm's hook we managed to dismount the chambers central lid.

Before doing anything else, we dismounted the near S2 and 12um mylar foil.

A new iris arm for the near iris needs to be manufactured by the workshop in CIRCE. The workshop was closed for the end of the day, so we also stopped for the day.

On 20/11/2018:

At 9:00 we walked into the lab, David R reported he found all the pumps OFF. A thunderstorm occurred overnight causing a power outage.

Last night we had switched off the electronics (Preamp power, RAL amp rack, and NIM bin).

This morning we determined everything was ok to switch on.

Using eLog entries #26 and #27 as reference we mounted the following detectors and foils:

• Far S2: 2323-18, 12um mylar
• Near S2: 2623-26, 12um mylar
• Silicon pin diode: 0.9um mylar

The pin diode used in previous tests had something deposited (fingerprint?) on the crystal, so we replaced this with a new clean diode.

We mounted the detectors and foils inside the chamber, the target ladder was kept in its configuration with all blank frames (see eLog entry # 41). See attached picture 1 for the 12um mylar mounted in front of the far S2.

We mounted preamp I on the near position and preamp II on the far position, as will be used during the measurement.

We sealed the chamber to ensure it was light tight.

We applied pramp power, expected currents were drawn.

With no S2 bias we see high noise on the majority of the RAL amplifiers for both preamps I and II. We switched off the lab lighting and found the chamber was indeed light tight - there were no observable changes in noise.

We discovered CH2 of the Silena HV module does not supply bias.

We applied -10V bias to both S2's. The far S2 is biased using CH1 and the near S2 is biased using CH4 of the HV module. The leakage currents read: Far S2 = 0.35uA, Near S2 = 1.81uA.

With bias RAL X CH 0 baseline RMS noise ~ 55mV.

We biased the pin diode with its operating -70V using CH3 of the HV module, leak I = 0.01uA.

We decided to switch off all biases and prepare for tests under vacuum with an alpha source.

CH1 and 4 of the HV module were set to -130V ready for the S2's

On 19/11/2018:

During the vacuum test - see eLog entry #43 we performed noise tests on the preamplifiers with no S2 detector connected

First we performed a "tabletop" test - the preamplifiers were not connected to the chamber.

Preamp I for the near S2 is connected to RAL modules (reading left to right): X, XII, XIII, R, S, Q, U, and W, via long (~5m) preamp - ICU cables 13, 14, 15, and 16

Preamp II for the far S2 is connected to RAL modules (reading left to right): I, II, XI, IV, V, VI, VII, VIII, via long (~5m) preamp - ICU cables 0, 1, 2, and 3

We powered preamps I and II with + and - 15V. The power supply shows the correct currents drawn: ~1.5A for +ve and ~0.75A for -ve

We found our test 16 pin cables #45 had a dead channel 0, we switched to cable #46 which shows all 8 channels working.

We found the following dead channels on the RAL modules:

We mounted preamps I and II to the top of the chamber. We mounted preamp I on the far S2 mount and preamp II on the near S2 mount, however we were not connecting to the S2's and so continued with the electronics tests.

Now we saw the following dead channels on the RAL modules:

We checked the signal to noise ratio for RAL X CH0:

The input pulser amplitude = 50mV, the RAL analogue amplitude = 950 mV, the RMS noise = 40mV. The S/N ~4.2%.

We stopped tests for the day.

On 19/11/2018:

We mounted the following in the chamber:

• Iris frames - no S2 detectors or mylar
• Si pin diode mount with 0.9um mylar - no diode
• Target ladder with blank frames - same configuration as elog entry #41

At 15:20 we started roughing pumps Ecodry 1 and 2. We opened the manual gate valve followed by the T1600 valve.

After reaching ~10^-2 mBar we started the following turbos:

• Up 1
• Up 2
• Down 1
• Down 2
• T1600
• Entrance 3
• CSSM

By 15:30 the CSSM turbo had reached 56 krpm operating speed and the Up and Down turbos had reached 833 Hz operating speed.

At 19:51 just before we left the lab the pressures read, in mBar:

• TPU1 = 3.7e-6
• TPU2 = 6.9e-7
• TPD1 = 1.0e-6
• TPD2 = 1.2e-6
• CHUP = 6.0e-6
• CHDW = 1.4e-5

On 19/11/2018:

During the target ladder calibration (see elog entry #41) we also replaced the collimator (thickness ~24mm, diameter 3mm) located immediately upstream from the target ladder - that is between the upstream and central sections of the chamber. We mounted an aluminium collimator (thickness ~1mm, diameter 5mm). See attached picture 1.

Using the same telescopic sight as that used for the target ladder calibration, we aligned the 5mm collimator with the beam axis.

On 19/11/2018:

There were three CH2 targets already mounted on the target frame, CH2 III, IV, and a damaged target. We dismounted these.

We noticed these previous target were mounted on the incorrect side of the target ladder, resulting in them being offset upstream from the central axis of the target ladder. This means for the previous tests in February and April 2018 the targets were mounted 3mm (target ladder thickness) upstream from the central position of the ladder.

We mounted blank 10 and 3mm target frames onto the target ladder in the correct centralised position, see attached pictures 1 and 2.

We performed the target ladder calibration using a downstream telescopic sight. The calibration is in agreement with the previous February 2018 calibration.

See attached picture 3 for the calibrated positions, this table is located on the magnet downstream of the chamber.

See attached for Electronics Channel Map spreadsheet.

This is valid for the February 2018 Beamtime; it maps out the Far S2 Strips onto the ADC channels

A map should be produced and updated for each beamtime to ensure S2 Strip -> ADC Channel is correctly documented.

Date: 07/04/2018

Began dismounting detectors:

• All detectors powered off
• Closed line and quadrupole valves
• Preamp power off
• Stopped turbos
• Closed manual gate valve and T1600 Backing valve
• Stopped Ecodry 1 and 2 roughing pumps
• Switched off CAMAC and RAL electronic crates
• FC - 0 suppression voltage switched off (was set to -360V for beam measurements)
• Switched off both NIM crates

After venting the chamber I dismounted both S2 detectors and the 12um mylar in front of each detector

I also dismounted the diode from the chamber, but left the 0.9um mylar glued onto the 4mm diameter metal collimator

I left the target ladder in the chamber

I remounted the central and downstream lids onto the chamber, the diode mount with mylar was left mounted on the central lid

We performed a general cleanup around the lab of the tools used during this shift

At 19:30 we left the lab ^_^