Choose timezone
Your profile timezone:
ATF2 weekly meeting
→
Asia/Tokyo
Webex, ATF LC mtg room (Universe)
Webex, ATF LC mtg room
Universe
Kiyoshi Kubo
(KEK)
-
-
15:00
→
16:00
webex sessionConvener: Dr Kiyoshi Kubo (KEK)Minutes of ATF2 meeting 20120706
Presentations:
We have the two analyses on the swapping performance, which are complement studies indeed.
G. White showed that swapping has no significant effect for any of studied optics, BX2.5BY1, optimized BX10BY1 and present BX10BY1 (linear Twiss rematched from BX2.5BY1).
However, the present BX10BY1 is not enough for achieving the 37nm with the TWISS mismatch or large (horizontal) emittance observed by the OTRs. Optimization of strengths of all quadrupole and sextuple magnets is necessary to squeeze the beam size.
He also discussed on considerations for QD0/QF1 BPM removal for mitigate multipole field error of the final doublet.
T. Okugi showed in his slide-4 that there is no significant effect of the swapping up to beta*_x=6mm with the re-matched optics by using additional corrections of Ychro, Ygeom and SK1FF knobs, i.e. the beam size of less than 40nm can be achieved. Ychro and Ygeom are another multiknobs by changing strengths of 5 sextupole magnets in the final focus system.
He also reported effects of multipole field of final doublet and effect of additional skew quadrupole corrector.
1, Quad swapping in FF
Both G. White and T. Okugi reported that no significant improvement is expected by swapping magnets.
We decided that we do not swap magnets in this shutdown, because it would be risky with small expected benefit (also, the alignment team has other things to do).
Swapping in winter shutdown may be considered, if further studies show significant expected improvement.
There is a different opinion that we should make the beamline as good as possible.
2, Multipole field induced by feedthrough of S-band BPM attached to the Final Doublet (FD).
G. White (and SLAC team) proposed more study of the magnetic field.
(Report of Okugi also showed importance of multipole field of FD)
For studies: T. Tauchi will send drawings of the BPM to C. Spencer. Spencer will send instruction of magnetic field measurement to Tauchi.
3, Skew Sextupole Correctors
Okugi suggested adding a skew sextupole corrector (in addition to SK1FF).
More studies necessary on the effectiveness and effects of misalignment of the correctors.
White and Okugi will make reports on this issue in the next meeting.
4, Actual size of carbon wire at IP
Direct measurement of the wire was proposed by White.
N. Terunima will try, though it may be difficult to measure absolute size accurately.
5, Schedule of Oct-Dec run
We agreed:
- - - - -
October (2 weeks)
? “commissioning” of upgraded IPBSM
? Attempts at 30-174 degree mode tuning?
? Re-commissioning of linac with modulator upgrades
? 3Hz operations (DR BPM problem -> ask Fermi Lab)
? DR optics check, emittance tuning
? Set up and calibration of monitors
? Study issues
? Low-emittance extraction and stability study
? IP matching
? IPBPM setup & alignment of FD orbit / IPBPM system with IPBSM detector
? Other ?
November 5-16 (2 weeks)
? Attempts at 30-174 degree mode tuning?
? Written procedure of tuning plan.
? Further student “on-the-job” training
November 26 ? December 21 (4 weeks)
? Continuous tuning
- - - - -
K. Kubo will distribute this schedule and ask collaborators to send; any other study items or things to do, and their possible travel plans.
We will discuss details in the next meeting.
6, Schedule of meeting
We will have meetings on 7/13 and 7/20.
No meeting 8/10 and 8/17.
We will decide later for 7/27, 8/3, 8/24 and later dates.
7, Agenda of next meeting (7/13)
Detailed Schedule of Oct-December
On skew sextupole correctors (Reports by White and Okugi)
and IP Multiknobs
How to write common tuning procedures on Wiki with instructions. (? may be ?)
IPBSM status report
Planning next meetings
8, White and Okugi will report summary of modeling of multi-knobs in next-next meeting.
- 15:00
- 15:10
-
15:20
Discussion and decision of Magnet Swap 20m
-
15:40
Schedule of Oct-Dec Run 10m
-
15:50
Plan of future meetings 10m
-
15:00
→
16:00
