Procedure for Phase A.8:
 
Step
Activity
Who
Priority
A.8.1
Prepare ramp, single beam, ring 1
    1

.01
Snap–back prediction, incorporation into functions, decay at stop point to be anticipated.
MA/OP
1

.02
450 GeV trim incorporation.
OP
1

.03
Prepare RF [Note 1].
RF/OP
1

.04
Transverse feedback ON.
  

 2

.05
Load Power Converters functions.
OP

 1

.06
Collimators (however, not ramped during first attempts).
OP

 2

.07
Timing table configured and loaded in the CBCM.
OP
  1

.08

 BLM thresholds up the ramp - check.

BI/OP

 1

.09

 TDI, TCT, TCLI OUT. Kickers OFF.

OP

 1

.10

 Check BLM threshold table (energy dependent).

BI/OP

1
A.8.2
Ramp single beam;  ring 1
    

.01
Send timing event: Start Ramp.

 OP

  1

.02
Monitor: Lifetime, tunes, orbit, energy, beam losses, beam sizes (synchrotron light).
OP
  1

.03
Measurements [Note 2].

 OP/RF

1/2

.04
Feed-forward of measured frequency offset for eventual switch to synchro-loop operation.
RF
2 Parasitic

.05
Feedbacks [Note 3].

OP/BI 

 
   - Orbit feedback  

1
   - PLL  

1
   - Tune and Coupling  

2

.06
Tracking [Note 4].
OP
1

.07
Transfer functions (may be difficult).
MA
2

.08

 Chromaticity (RF modulation synchronized with orbit/dispersion).

OP/BI

1

.09

 Beta beating measurement at intermediate energies – local orbit checks. OP/ABP 1
A.8.3
Post Ramp analysis
    

.01

 Feed-forward of measured frequency offset for eventual switch to synchro-loop operation. RF/OP

2

.02

 Feed-forward of tune measurements. OP/ABP

1

.03

 Analysis of orbit and feed-forward of orbit corrections (if Global Orbit Feed-Back (GOFB) not operational). OP/ABP

1

.04

 Analysis of GOFB correction and feed-forward if operational. OP/ABP

2

.05

 Chromaticity.    

.06
Beta beating.
RF/OP
1
A.8.4
Beam at Intermediate Intensity
    

.01
Follow decay of tune, chromaticity and orbit.
OP/ABP
1

.02
Measure tune, coupling, orbit – only correct if really required.
OP/ABP
1

.03
Check optics [Note 5].
OP/ABP
1

.04

Beam dump commissioning [Note 6].
BT
1
A.8.5
Iterate
    
.01
Dump at progressively higher energies. Proposal: 7 steps from 450 GeV to 7 TeV.
OP
1
.02
Repeat previous steps at each benchmark energy.
OP
1
.03
The full procedure will have to be repeated for beam 2.
OP
1
A.8.6
Commission collimators and protection devices in the ramp [Note 7]

 Coll/BT

 1
A.8.7
Commission feedback using PLL [Note 8]

 BI

 1

 

Notes on procedures

Note 1: during commissioning we ramp with radial loop and we can feed-forward the measured frequency correction into the function (in operation we use synchro loop). Procedure:

  1. Load model RF functions.

  2. Radial loop on – to be done after last injection and before start ramp.

Note 2:

  1. Capture losses (flash loss of out-of-bucket beam at start of ramp).

  2. Continuous measurements of frequency response of loops during ramp (RF/Parasitic).

  3. Bunch length (emittance growth), RF noise. (RF/Parasitic).

 

Note 3: Feedbacks

  1. Orbit feedback:
    • Synchronized acquisition and feed-forward.
    • Global orbit feedback a.s.a.p.
  2. PLL:
    • Continuous tune, coupling.
    • High priority: feed forward.
  3. Tune and coupling:
    • First ramps can be attempted w/o these feedbacks, however, in our interest to commission them a.s.a.p. Critical will be measurements to monitor variations during snap-back and in the ramp.

Note 4:  the real time orbit acquisition allows us to check the relative tracking during the ramp with similar or better accuracy in delta (use difference w.r.t. injection) as compared to injection.

Note 5: IR2 optics changes at some point in the ramp.

Note 6:

  • Check energy tracking calibration (MKD, MSD, MKB).

  • Orbit/aperture.

  • Extraction trajectory.

  • Instrumentation.

  • Kicker timings, retriggering.

  • Post mortem and XPOC.

The first commissioning of the LBDS with pilot is done in A.3.3 and A.3.7.

Note 7: Procedure should have  essentially been commissioned without beam. Watch closed orbit at collimators and related beam losses. No cleaning issue for pilot. Primary needs to be defined. 10σ TCDQ at 450 GeV; primary closer - could leave for first attempts based on findings during 450 GeV optimization.

Note 8: If not done already.