Laser surveying team worked till 11. Chamber was too high by 3mm close to the jet target and 6mm by the turbo pump (towards the dipole). 

CARME lowered appropriate amount using bolts under CARME feet. Height checked using a laser on the centre point line of the middle flange turbo end and mid point on the front of the chamber (see images). During lowering front foot swapped and valve supports moved slightly to give more clearance for opening. ~13cm clearance for opening the chamber currently. 

Pipe and single bellow connecting CARME to dipole replaced by two bellows and new pipe. Rest of open ports on chamber closed. 

Thermocouple feedthrough flange installed under the motors flange in the turbo pump section. One internal thermocouple hooked onto kapton cable connected to MACOR and one thermocouple left floating in the chamber. Floating thermocouple corresponds to right output on feedthrough, thermocouple on kapton corresponds to left output on feedthrough. Image taken from flanges at the top of the chamber, quality is poor due to lack of maneouvering space.  

Baking frame partially assembled around the chamber. Full assembly requires removing valve airlines to get under the valve pipe, will be done Monday morning. Took measurements for the RGA around the chamber, should be able to fit in multiple positions without conflict with baking jacket. 

Test

Noticed bursts of high energy noise on aida01 and aida02 during run 47 and 48.

Good events rate jumps from 10-20k range to 250k. ADC data items rate jumps from 0-1 to 2k. Data rate being written increases to ~2500 kb/s from ~20 kb/s

Effect appears short lived ~30s at a time. On 18/2/22 the asic was check loaded which appeared to remove the increased rate but due to the time taken to asic check the burst had already finished.

Asic 2 on aida01 and asic 1 on aida02 are affected. See attached plots.

Fast comparator threshold HEC currently set to 0x2 for all

Zoomed in region of aida 1 asic 2 and the same region for asic 1 to see the difference are attached.

Upper part of the frame was mounted. In order to do so, the valve was closed, turbo wire and hose were disconnected and then connected. Valve was opened again. See pictures 1-2.

Bottom part of the tent was constructed with 3 heaters (from one of the controllers) at the front, 4 in the middle, and 4 at the back (4+4 from the other controller). See pictures 3.

Thermocouples were tested and connected to TC08 modules.

Wire connecting to four heaters was damaged which caused a spark and sound when the upper tent was being constructed. This caused a power failure two times, turning off all three pumps. The upper valve was immediately closed. Power supplies of heaters were disconnected and pumps were turned on again. Valve was opened again as well.

Construction of tent is paused. Waiting for the wire to be repaired by tomorrow and start again.

11.15 Pirani 1.0e-03mbar IE514 2.72e-08mbar

16.35 Pirani 1.0e-03mbar IE514 2.61e-08mbar

10:10  IE514 2.0e-08mbar

Upstream part of the CARME is covered.

09:26  IE514 1.96e-08mbar

16.40 CB/ML install fibre optic cable from patch panel beneath dipole downstream of YR09/CARME chamber to VETAR2 front panel fibre connector - see attachments 1 & 2.

VETAR2 LCD display changes from magenta to cyan.

DAQ stop. DAQ reset. DAQ setup.

All system wide checks OK.

WR timestamp control - attachment 3 is timed 16.43.11 UTC+1

WR timestamp 0x17B101E7 7FCD1ACD -> 1707147827543349965ns -> 1707147827s -> Monday, February 5, 2024 3:43:47 PM UTC ( https://www.epochconverter.com/ )

One of the detectors was damaged while mounting (see pictures 1-3).

Second detector was found already damaged when opened (see pictures 4-5).

9:30 Bias remained stable overnight - 60V 2.95 uA.

10:00 No grounding attached initailly. Pulser ON, lots of noise across all ~250-300 kHz across biased detector. Waveforms and histograms saved to /tmp. Pulser width for aida 6 ~300 channels. Aida 7,8 similar, aida 5 producing no ADC data. 

11:00 Grounding connected as in elog 181. Rates decreased to ~180-250 kHz. Waveforms and histograms saved to /tmp. 

12:00 Bias slowly increased too 100V giving a leakage current of ~3.5 uA which was stable for several hours. Bias varied between 60V and 100V for noise reduction perposes, 80V deemed least noisy at the time, noise still ~180-200 kHz

13:30 New grounding trialled. Bottom detector removed from pulser and grounding loops so that only the biased detector is grounded. Bias set to 80V

14:00 Rates significantly reduced for aida 6,7,8 - aida5 still producing no ADC data. Rates are in range 15-50 kHZ with noisy channels accounting for most of the rates. Waveforms and histograms saved to /tmp. Pulser peak on aida 6 ~300 channels. 

16:00 Aida 5 fee investigated to reason it is not producing data. FEE was not properly connected to ERNI connector due to incorrect installation of black adaptor card mount. Adaptor card mount reinstalled and fee remounted. Aida 5 now produces ADC with similar rates to aida6,7,8. 

During investigation of aida5, aida4 and 5 were swapped. Config files relating to MAC addresses, polarity etc of FEES has been updated. Elog 175 will be appended to include this swap.  

19:00 Bias set to 80V, DAQ running with pulser off to allow for alpha detection overnight. 

Connected all FEEs.

The two top fees corresponding to the bottom right detector are connected to damaged flexi rigid PCBs. The top one is missing an pin that should not be connected to anything, while the bottom one has a slightly cracked connector and is missing the top left pin. Spares should be in Edinburgh.

Found that the flexi rigid PCB connected to the bottom most FEE of the bottom-left detector has a damaged ground lemo connector. Possibly pulled during mounting? The bias cables were off most of the time. Seems to bias fine using the other bias lemo, but not ideal.

Attached, a V-I plot of the four detectors being biased. Note bottom-left was only biased to 120V vs. 150 since it shows relatively high leakage current. Time is wrong - bias was given over ~2 minutes. Unclear why the x-axis is incorrect.

Leakage currents for all detectors, and especially bottom-left and bottom-right drop significantly waiting a sufficently long amount of time, e.g. down to ~5.5 uA after 15 minutes.

To create this plots in case it is needed.

ssh to CARMEbakingpi

cd Programs/caenlogger

python3 caenlogger.py

This will capture the data and pass it to the server (carme-gsi) in ~/caen_current.dat where they will be APPENDED. Delete / save / move the file from the CARME server if required. Backups are in Programs/caenlogger/bias_logs

THEN Bias on

THEN

ssh carme-gsi

cd Programs/caenlogger

gnuplot plot_current.gp

The left (inside ring) bellow for the motors rod was replaced.

Replacing the bellow involved;

• One person holding the metal plate the detectors are mounted on (cabling remains plugged in) while the operation is performed. 
• The motors box is supported by the cryring crane by its mounting points
• Bolts on the flange connecting to the chamber can then be undone. The whole motors section (rod included) is then moved out of the chamber using the crane and someone to stabilise the rod as it slides off the detector plate. 
• Once off the chamber, the steel cover can be removed by disconnecting from the flange and from the motors box. Best to perform on a table. 
• The bellow is then removed by removing the nuts on the small flange (kf 25) connecting the bellow to the box. The bolts for these bolts are very long and go through the motors box from the moving metal plate seen in the attached image. 
• Follow these steps in reverse to install the new bellow. 

While replacing the bellow, it was noticed the long bolts for the small flange were too short. It was therefore very difficult to re-attach the nuts with any torque. The thickness of the head of the bolts was shortend to effectively lenghten the bolt which was sufficient to tighten the nuts. New bolts should be bought in case of replacing the bellows again. 

The orbit of the beam in the ring was re-configured so that the beam position is more central.

With the target density at ~6e11 at/cm2 this allowed a target overlap scan using the beam lifetime to be performed. 

Beam put into bunched mode to allow the number of particles to be observed on Grafana.

The number of particles injected at the start of the cycle was then compared to the number of particles at the end of the cycle to gauge the % of the beam lost.

A flat top region was observed where >99% of the particles in the ring were lost. The centre of this flat top corresponds to a horizontal beam position of 1.0 mm

Attachment 1 - Grafana plot of beam intensity

Attachment 2 - Plot of overlap

Target density this morning had stabalised at 7e11 at/cm2

This is sufficient to test the beam/target overlap using the lifetime of the beam in the ring.

Previous attempt at this method was done at 1.5e11 at/cm2 where lifetime from residual gas and target are essentially the same.

Beam set to bunched. Beam position varied by 1mm and the number of particles in the ring taken from Grafana plots. Particles at injection compared with at dump.

Significantly more beam loss at > 8 mm beam position with highest value at 8.75 mm. This is the maximum we can move the beam.

Test repeated with no target. Same beam loss rate for all positions. We see a clear difference with the target only at positions > 8mm.

Test repeated with original electron cooler voltage Gleb tuned with last night. Same outcome -> cooler voltage has no significant impact on overlap (for 0.1V at least)

Overlap using count rate over 7.5 minutes also tested. DSSD 1 (top right) used as gauge as no beam stripe is seen in this detector. 

At horizontal position 4 mm (previous estimation of overlap) we saw a small increase in counts around 4.7 MeV with the target off compared to target on (76 vs 57)

At horizontal position 8.75 mm we saw a large decrease in counts around 4.7 MeV with target off compared to target on (95 vs 290)

It appears clear the overlap is at 8.75 mm. Future runs will use this as horizontal beam position.

For 200keV the optimal horizontal position is -5mm.
For 250keV the optimal horizontal position is -2mm.

Both values are already given to the operators, so tomorrow we can just switch to 200keV and go on :)

Nonetheless, we now went to 250keV and start measuring.

14:01

Run 36 started.

We put both detectors to the fully out position. Detectors then driven IN using the pnuematic motor only once the beam is ready and driven fully out before beam dumping.

We notice the right arm is significantly slower than the left arm and does not manage to go fully out before being told to go back in. This is not ideal.

Run stopped.

14:10

Run 37 started

Right arm is positioned at pot = 70.49 and remains stationary. The left arm is moved with the ring cycle. When IN left arm pot = 62.71 mm. When out left arm pot = 18.89 mm

Movement signals are being saved to jan MBS system and can be used to seperate out injection periods on other runs where both detectors will be stationary.

All beam and target settings are the same as for Run 35.

Spectrum browser rates for each FEE when left arm IN shown in (attachment 1). Rates dependent on beam cycle, when detectors move out, rates in left arm drop significantly as expected.

XY and energy histogram plots from monitoring code (attachments 2+3)

We see the Rutherford much more well defined on the bottom left detector now (it is further in and halo effect is reduced). Still some low energy counts (may be due to detector movement -> need to test without beam)

Top left detector energy histogram looks a lot different, still much halo effect.

we will collect some stats for 30 mins or so

14:57

Run 37 Stopped. Run 38 started.

Faraday cup to the ring closed. No beam in the ring. Left arm of the detectors still moving IN and out of the beam with the ring cycle.

Very little counts observed in energy spectra.

15:02

Run 38 stopped so Gleb can change the beam energy. Run 39 started.

15:30

1.5 MeV/u beam currently being tuned

Target is ON, setpoint = 135 K

System checks OK - white rabbit fail diff ~ 9

Temperatures OK

Merger OK

Data rate ~ 1400 kb/sec

Leakage current ~ 3.41 uA

Aida 1 and 2 missing channels from previous days appear working on stat layout 2 and xy pixel total plot (attachment 3)

17:12

Beam tuning complete. See attached Ex rate histogram.

The cryo compressor is being turned OFF for around 1 hour to remove any frozen nitrogen which may be the cause of the increased pressures observed.

Beam OFF to do so.

System checks OK - white rabbit fail diff ~ 9

Temperatures OK

Merger OK

Data rate ~ 200 kb/sec

Compressor OFF, setpoint on controller is 273 K

18:51

Pressure in the ring recovered quickly after closing valves to gas jet (attachment 5)

Increasing temperature caused a large spike in pressure in the inlets. E1 turbo briefly shut down due to the pressure increase, since restarted and pressure back in the -4 mbar range. (attachment 6)

Temperature being decreased

Beam back ON

data rate ~ 1500 kb/sec

merger OK

Temperatures OK

System checks OK - white rabbit diff ~ 12

21:58

After cooling the jet target, expected density is not achieved. E4 pressure is ~4E-10 mbar compared to ~2E-8mbar previously. Temperature reduced to 127K E4 pressure increases however stilll within -10 mbar range.

With beam on target we see rutherford peak at ~3 MeV, however it is much reduced.

Beam OFF to investigate inside the cave.

Decreasing temperature of nozzle in 0.5 k steps to see effect on E4 and S1 dump.

05:00

Beam ON ~2E6 pps, still fluctates between 2e6 and 6e6 (like a step function)

Target ON and open to the ring

YR09xxx ETarget ~1.8e-10

Target E4 inlet pressure 8.3E-9 mbar

Dump S3 ~ 6.8E-10 mbar

Nozzle temperature 150 K

Run 54 started, monitoring code restarted.

06:47

Beam ON ~2.0E6 pps, still fluctates between 1e6 and 6e6 (like a step function)

Target ON and open to the ring

YR09xxx ETarget ~1.8e-10 (saturated)

Target E4 inlet pressure 8.0E-9 mbar

Dump S3 ~ 6.6E-10 mbar

Nozzle temperature 150 K

Run 54 started, monitoring code restarted.