Week 47

Machine coordinators Oliver Bruning and Jorg Wenninger

Day	Date	Beam	No beam	%
Friday	20-Nov	5	0
Saturday	21-Nov	15	9
Sunday	22-Nov	8	16
Week 47	Beam/Nobeam	28	25	53

Started with beam just after 18.00 Friday

Beam 1

• 18.50 TDI out and beam1 to IR3 (after some problems with BLM signals)

• 19.00 beam through CMS

– beam1 through to IP6 è quench in S56 (cell A12L6)

– Provoked by trajectory correction. Understood.

• 19.55 Starting again injection of Beam1

– corrected beam to IP6, 7, 8, 1

• 20.40 Beam 1 around and makes 2 turns

– Working on tune measurement, orbit, dump and RF

– Beam makes several hundred turns (not captured)

• Integers 64 59, fractional around .3 (Qv trimmed up .1)

• 20.50 Beam 1 on beam dump at point 6

• 21.50 Beam 1 captured

Beam 2

• 22.15 Switching to Beam2

• 22.20 Beam dump due to beam losses on TDI

• 23.10 Start threading Beam2

– Round to 7 6 5 2 1

• 23.40 First Turn Beam2

– Working on tune measurement, orbit, dump and RF

– Beam makes several hundred turns (not captured)

• Integers 64 59, fractional around .3 (Qv trimmed up .05)

• 24.10 Beam 2 captured

Saturday 21^st November

Pre-cycle magnets, pick up the pieces, access

Beam 1 again from 16.00

RF fine tuning

BI on tune, orbit and more

Circulate and not dump

Beam stays an hour (I=0.9I₀), Lifetime 10h

From 19.00

RF finished for now

Dispersion and Chromaticity

Kick response (with circulating beam 1) overnight

Sunday 22^nd November

Pre-cycle magnets, pick up the pieces, access

19.00 Vacuum problem in LINAC (pump power supply)

Switch to beam dump tracking tests

Test ramps with all elements (collimators)

Beam 2 again from 24.00 (03.00), circulate and dump

RF phase adjustments

Tune orbit coupling chromaticity measurement / adjust

Significant chromaticity trims needed (-10 both planes)

Coupling also worse than for beam 1

Splash events for ATLAS done

Interlock tertiaries in 1 (other 3 IP already done)

Circulate and not dump

Lifetime about 3 hours

RF phase lock not on