Note issue #1887

Monday 7th November, 14:00 GMT, MICE meeting room.


Alan Young
Victoria Blackmore

Statistics on empty data
1. We have about 15000 events per momentum setting after Rogers cuts
2. Is that sufficient? study at ~ 0.1 MeV/c momentum bias which is about 1 % of the energy change; transverse variables have better resolution; demonstrate px/py resolutions at the 1 % level as well which is probably enough.
3. We can't check emittance change for empty data set at required precision - need about 50,000 events for that (see J.Cobb MICE Note)
4. Magnet alignment; we cant do alignment empty and apply the result to full - because the magnets have to move to do the install.
DECISION: We can live with existing empty data sets; but would be nice to have "empty" with more statistics to check for null result

Statistics required on full data
1. We didn't go into too much detail - but a "couple of days" on each setting should be sufficient. In which case we aim for about 10 settings (with some settings getting higher priority and aiming for better statistics - TBD).
2. The feeling was that the concern about emittance bias/transmission issues was sufficient that a beta/acceptance scan has higher priority than momentum scan.


Discussion of proposed settings...

  • A nice setting - but how does it fit into a paper?
  • ACTION: Give Ao the settings shown in slides; for 7500 he can use the ones on the wiki for best acceptance
  • ACTION: Add - max beta function in the TKD region plot
  • ACTION: Check - low beta/high acceptance region for flip i.e. "cape of good hope"
  • DECISION: Flip mode looks better. We should just start in flip mode
  • High transmission - how does this fit into a paper?
  • What emittance reduction is available?

Updated by Rogers, Chris over 6 years ago ยท 6 revisions