17:00

Scraper tests conducted. We tried moving in the scrapers both at a fixed position throughout and also moving with the injection cycle.

We were unable to find a good position with the scrapers that did not produce significant scattering in the detectors.

Therefore we have moved the scrapers back to the fully out position.

Run 42 started.

We have increased the storage time to 10 reps (1 minute) in order to investigate the shoulders on the 3He peaks online and whether it is likely from injection. I think it is likely just a calibration issue

D+ beam deuterium target. D+ beam energy is 0.75 MeV/u. (beam calc calculation is 0.7619 MeV/u). See previous entry for beamcalc.

Beam calc - Attachment 1

Target density is about 2e12 at/cm2

All four detectors positioned fully out and stationary.

Left potentiometer = 18.86 mm

Right potentiometer = 19.8 mm

Ring cycle time is 60 seconds. Note we see some hydrogen in in the spectrum, this disapears after a few seconds.

Target T1=30.0K, T2=31.6K.

Nozzle position x=-2.96, z=1.72 mm

YR09-Etarget pressure = 2.0e-10 mbar.

Cooler set value = 439 V, 15 mA. Read value = 439.81 V, 12.88 mA

All leakage currents look good

Beam position. Vertical =0.0mm , Horizontal=-1.5 mm

Beam intensity ~6e8 on bunched beam, 6e8 on coasting.

Data rate ~ 416kB/s

slow comparator threshold to 0x24 (360 keV)