[Mott] Mott work summary for Tuesday, Feb. 11

[Joseph Grames]

Mott work summary for Tuesday Feb. 11th is shown below. For those off-site you can access electronic logbook (https://logbooks.jlab.org) with your JLAB username and password to view all entries, pictures, plots, etc.

In spite of being down majority of shift, good progress on addressing instrumental asymmetry.

1. Verified MAD correctors work fine.

2. Measured ~2G field from VIP3D00, fabricated mu-metal shield and reduced to ~1G.

3. Down 1hr for PSS issue

4. Down 1hr for 0L valve FSD configuration issue (not allowed to mask)

5. Restored 5.0MeV w/ 499MHz beam to 1um Au target

6. Compared instrumental asymmetry and rates for different setups:
a) steered in 0L, but centered on 3D => no improvement
b) centered in 0L, but steered in 3D => no improvement

7. Identified that we hadn't set dE HV large enough resulting in descrepant E/dE coincidences

8. Down 3hr for 0L valves
a) confused state required iocin2 reboot
b) fast valve PS failure required replacement

9. Recovered beam and adjusted PMT HV for dE pulse height closer to ~200mV

10. L/R elastic rates coming into balance and instrumental asymmetry consistent with zero.

11. Ending shift with three dump runs: degaussed, +5A, -5A; to identify that dump is not affecting elastic signal. Will be able to better address with 31MHz, but no more time tonight.