Gafchromics foil was mounted on empty brass frame back to back with Li sample

Neutron beam goes well through the sample. Centered ~1 cm from sample center. Conclusion: no changes needed (too risky to make it worse and it is ok now)

dE Detector: W1-20 3186-9 20 um

E Detector: W1-150 3458-4 144 um

Voltages and Leakage Currents:

dE: 6 V, 0.02 muA

E: 50 V, 0.05 muA

MSL type W1(SS)-20

3186-9  20um Depletion voltage 3V Operating voltage 6V
3585-12 20um Depletion voltage 2V Operating voltage 4V

MSL type W1(DS)-150

3458-1 157um Depletion voltage 22V Operating voltage 52V
3458-4 144um Depletion voltage 18V Operating voltage 48V

• Start 9th August, access to EAR-2 11 am earliest but can start in rack area before
• Setup to be used: 1 dE (16 strips, 20 um thickness) + 1 E (16x16 strips, 150 um thickness. We have a spare for each thickness
• Sample and detectors to be mounted on the same flange

Things to check:

• alignment with beam centre (lasers and/or gafchromics foils)
• is the setup stable to knockes, can all detector / sample positions be well reproduced when making changes

Once setup us completed:

• checks with pulser
• mounf LiF sample number 3 and run with neutron beam
• check that all strips have signals
• confirm shape of gamma flash and that short times can be anaysed in both detectors (~1.8 us after flash)

If everything working:

• measure LiF-3 and the switch to Al-26
• towards end of the run we can also measure B-3 and the empty brass frame (Frame without mylar)
• proton statistics: 1E17 LiF-3, 1F17 B-3, ~3E17 Empty, 5.5 E18 Al-26

Travel times

Nick: 8-16, Annie 8-12, Tom, 7 -?, Claudia, 8-10, Emmanuel asap until end of run

Measurement runs until Octover 2nd. Disassembly by Nick and Emmanuel.

additional trips during the measurement as required (if something breaks/fails etc. )

Attached: photos of previous setup

TO Do: MCA availability at nTOF for quick noise checks (Nick)

            how many  channels in 14 bit, how many 12 bit (Nick)

          depletion voltages   for detectors (Tom)

          Register the eqipment at CERN as Edinburgh property (Claudia)

Box 1

1. RC412 Cables

2. Screws and parts for rails

3. Small rails

Box 2

1. Vacuum valves

2. IDC cables

Box 3 (Detectors)

1. WI-20

3186-9

2. WI-150

3458-4

3. WI-150

3458-1

Box 4 (Detector)

1. WI-20

3485-12

*List

**We also have the tube for the long rails

21:15 Changed from detectors in-beam to boron-10 sample 3 in-beam (in-beam measurement got 1000 triggers, 500 of which were dedicated). The sample was mounted identically to LiF 3. An attempt was made to replace the 20-micron dE detector with a 50-micron one, but the screwholes on the 50-micron detector did not match the 300-micron E-detector ones and therefore could not be mounted. 20-micron detector was therefore re-attached. Planning to run for 12 hours with boron than dismount.

After long beam-off, changed detector mount by moving it 2 cm forward into the beam, after removing LiF 3.

Increased detector-target (LiF 3) separation by 1.5 cm. Had to replace the support strut under the detectors due to the previous one being fuly retracted even for minimal target-detector separation. This change may affect detector rotation relative to the target.

DEED 6 and 9 no signal throughout the campaign.

EFED 27 high oscillations in baseline throughout the campaign.

The pulser has been switched from triggering from beam trigger to running at a 10 Hz rate, and will now appear in random places in signal traces. Planned to run overnight measuring LiF3, switch to empty + detector in beam in the morning.

Still using pulser triggered from protons. 12 microsecond delay from protons to gamma-flash + 11 microsecond delay from gamma flash to pulser. 20 mV pulser output into 50 ohm impedance (10 mV final output) of both polarities (using two pulsers, one NE pulser and one BNC PB5 pulser). Changed pulser setting to run with 11 microsecond delay for approx. 2 hour, then change to an overnight run with pulser running NOT triggered from beam.

Still using pulser triggered from protons. 12 microsecond delay from protons to gamma-flash + 1.75 microsecond delay from gamma flash to pulser. 20 mV pulser output into 50 ohm impedance (10 mV final output) of both polarities (using two pulsers, one NE pulser and one BNC PB5 pulser). Changed pulser setting to run with 5 microsecond delay for approx. 1 hour, then change to 10 microsecond delay.

Photographs of assembly up to the first pulser test with LiF3.

Changed from LiF 4 to LiF 3 after running with LiF 4 overnight (run title on n_TOF DAQ was not updated to refelect the change, and still says LiF 4, but the material setting of the run states correctly that hte run is with LiF 3).

Added pulser triggered from protons. 12 microsecond delay from protons to gamma-flash + 1.75 microsecond delay from gamma flash to pulser. 20 mV pulser output into 50 ohm impedance (10 mV final output) of both polarities (using two pulsers, one NE pulser and one BNC PB5 pulser). Planning torun with 1.75 microsecond delay for approx. 1 hour, change to 5 microsecond delay.