May 30

(return)

1. GHADDG4G - no signal observed
2. Machine experiment - research on k1-stability of various HADES configurations
3. very weak signals from 1 GeV 1e7 protons/s beam
4. gas grids OK, but screens often did not see beam (even TH2DFA)
5. observation: one has to move by about 0.2 1/m in 21D k1-space in order to destroy focusing on target
6. low quality data, GHADDF4 with frame grabber in video mode.

Data analysis

History of measured current changes in investigated magnets over night of experiment:

This shows the distribution of current measurements of GHADQD11, configuration 7453, from 00:00 to 00:10, converted to k1L using the official calibration curves:

This shows GHADQD11 data, configuration 0052, from 01:07:05 for 10 minutes:

This shows GHADQD11 data, configuration 3574, from 04:12:00 for 7 minutes:

This shows GHADQD11 data, configuration 5697, from 05:14:00 for 8 minutes:

This shows GHADQD11 data, configuration 7627 (last one), from 06:38:00 for 10 minutes:

Conclusions:

• the short-term stability (precision) of magnet k1L value setting is about 10^-6 1/m.

• at 10 min time scale some drifts and power converter regulations are already visible
• accuracy on k1L values:

• there is a regular shift between set and get k1L value (maybe due to accuracy of used calibration functions?)
• the difference has of course larger impact at low k1L value