“Intermediate” Filling Patterns

for the 2010 Heavy Ion Run Aim:

Devise LHC ion filling patterns with a number of bunches somewhere between 2 bunches/ ring (during first setting up) and the one with >100 bunches for higher luminosity

Content: Filling with 20 bunches/ring and regular spacing (apart gaps for abort gap and non- colliding bunches) Few batches from the 140/128/120 bunches/ring scheme

Outlook: Two proposals with ~20 bunches/ring

… amongst many possible schemes … criterion to choose one No dephasing of the two rings to optimize collisions schedule

Adopt (refine, optimize …) one of the schemes and discuss with people concerned (e.g. are two bunches spaced by 3700 ns feasible for SPS …)

       

October 2010 “Intermediate” Filling Patterns for the 2010 Ion Run C.Carli and J.Jowett 1/6

Filling with 20 bunches/ring and regular spacing

• Basic building block (corresponds to one SPS batch): two bunches spaced by 3700 ns and “Injection kicker”: 3725 ns

• 3 such blocks fill exactly one LHC quarter, leave out last batch for abort gap keeper• To obtain non-colliding bunches for all experiments, if 1st buckets encounter in point 1

– Remove batch 3 of ring 2 (colliding with ring 1 abort gap in ALICE)– Remove batch 6 of ring 1 for non-colliding bunches from both rings in all experiments

Ring 1 filling pattern (ring 2 similar – 3rd batch missing instead of 6th)

Batch 6 removedfor ring 1

Batch 3 removedfor ring 2

October 2010 “Intermediate” Filling Patterns for the 2010 Ion Run C.Carli and J.Jowett 2/6

Filling with 20 bunches/ring and regular spacing

Bucket number

Number bunches

Spacing (ns)

1 2 3700

2971 2 3700

5941 2 3700

8911 2 3700

11 881 2 3700

17 821 2 3700

20 791 2 3700

23 761 2 3700

26 731 2 3700

29 701 2 3700

Bucket number

Number bunches

Spacing (ns)

1 2 3700

2971 2 3700

8911 2 3700

11 881 2 3700

14 851 2 3700

17 821 2 3700

20 791 2 3700

23 761 2 3700

26 731 2 3700

29 701 2 3700

Filling sequence for ring 1 Filling sequence for ring 2

For completeness: filling sequence as defined via application in CCC

October 2010 “Intermediate” Filling Patterns for the 2010 Ion Run C.Carli and J.Jowett 3/6

Filling with 20 bunches/ring and regular spacing

• Collision schedules for ALICE and CMS

Ring 1 filling pattern (ring 2 similar – 3rd batch missing instead of 6th)

October 2010 “Intermediate” Filling Patterns for the 2010 Ion Run C.Carli and J.Jowett 4/6

Few batches from the 140/128/120 bunches/ring

• Basic building block (corresponds to one SPS batch) from 140/128/120 bunches/ring scheme• One blocks at the beginning of each quarter• To obtain non-colliding bunches for all experiments, add additional batches

– Batch 5 for ring 1– Batch 23 for ring 2

October 2010 “Intermediate” Filling Patterns for the 2010 Ion Run C.Carli and J.Jowett 5/6

Few batches from the 140/128/120 bunches/ring

Bucket number

Number bunches

Spacing (ns)

1 4 500

3961 4 500

8911 4 500

17 821 4 500

26 731 4 500

Filling sequence for ring 1 Filling sequence for ring 2

For completeness: filling sequence as defined via application in CCC

Bucket number

Number bunches

Spacing (ns)

1 4 500

8911 4 500

17 821 4 500

21 781 4 500

26 731 4 500

October 2010 “Intermediate” Filling Patterns for the 2010 Ion Run C.Carli and J.Jowett 6/6