Procedure for Phase A.3:

Details of activities: Sequence: circulate & dump, unless indicated otherwise

Step A.3.1: (pilot intensity): RF instrumentation final commissioning for pilot intensity [2 rings separate], check for 1 ring then for other

1. Check bunch 1 timing with revolution frequency and abort gap

   • Verify: 40 MHz clock and f_rev distributed and received by BI

2. Commission remaining longitudinal diagnostics if not already done in phase A.2

Step A.3.2: (pilot intensity): BCTFR and BPM checks with pilot intensity [2 rings separate]

1. Commission BCTFR in circulating beam mode

   1. Time in BCTFR with respect to RF

2. Calibrate BPMs system and correct: ring1, ring2, YASP

   1. Optional: fine tuning: correction of injection steering errors

   2. Time in BPM system - bunch tagging

      • Set turn clock with respect to end of abort gap

      • Check first turn, orbit, see if centered → feedback to RF

3. Commission real time channel for continuous orbit measurement with beam

4. Scan few (recommendation: all) orbit correctors and acquire all monitors - polarity and rough calibration

5. Flatten orbit in injection regions and dumping region

6. Use response data for first rough linear optics check ([1])

   1. Acquire trajectory data (not only orbit data)

      • trajectory data can be used to reveal where optics model problems have their source

Step A.3.3: (pilot intensity): First commissioning of beam dumping system [2 rings separate]

1. With circulating pilot :

   1. Sequence: circulate & dump (1 s delay - depends on lifetime)

   2. Check orbit correction works in point 6, at TCDQ and MSD

   3. With nominal optics and orbit information set TCDQ and TCS in IR6 to ~10 sigma and check setting with beam measurement ([2])

      • centering, aloss response, TCDQ/TCS tracking, ...

   4. Commission dedicated synch BPM signal

      1. check analogue signal from kicker trigger BPMs is correctly transmitted

   5. Adjust kicker timing - with single pilot (bunch 1) adjust MKD kick delay with respect to revolution frequency. Note UA access needed for each trim, so only 1 or 2 iterations

   6. Measure aperture with circulating beam (bump + BLMs)

      1. H: TCDS entrance, MSD exit

      2. H&V: MSD

2. With extracted pilot: sequence circulate & dump or inject & dump

   1. TD line BI commissioning

      1. BLMs, BPMSE, BPMD, BTVSE, BTVD, BTVDD, FBCTs

      2. BDI acquired data - check all beam-dependant transient signals  are acquired correctly for XPOC

   2. Check position of bunch dumped on TDE block - steer if needed

      1. Adjust energy tracking if needed - local intervention to change EPROMS

      2. Adjust IPOC/XPOC references if needed

Step A.3.4: (3 х 10¹⁰): Commission systems with higher intensity [2 rings separate]

1. Move in TDI

   1. Center around orbit and set to 10 sigma according to best available optics and orbit knowledge, no dedicated beam based alignment yet

2. BCT system (possible accuracy [3]):

   1. Commission BCTDC to give acquisition updates at 1 Hz

   2. Commission safe beam flag: 1Hz intensity measurement of BCTDC: acquisition + generation + distribution

   3. Commission BCTFR in bunch-by-bunch mode

   4. Commission beam presence flag (BCTFR): acquisition + generation + distribution

   5. Verify logic at SPS master BIC concerning LHC safe beam flag (can force false) and beam presence

   6. Commission lifetime measurement with BCTFR

   7. Cross-calibrate BCTDC and BCTFR

3. Tune Meter commissioning, chromaticity measurement:

   1. Commission chirped tune measurement using transverse damper (priority 1)

   2. Commission single kick tune measurement using MKQ & BBQ (priority 1)

   3. Commission chirped tune measurement using BQK & BBQ (priority 2)

   4. Commission head-tail chromaticity measurement  (priority 1) , need MKQ excitation

4. Initial BLM system commissioning: PARASITICALLY:

   1. Adjust thresholds on "accidental quench & learn basis" - PARASITICALLY (priority 1)

   2. Optional: lose/quench on purpose: which magnets to be quenched in case: [4] (page 5) (priority 2)

Step A.3.5: (3 х 10¹⁰): Lifetime optimisation - get to 1 hr [2 rings separate]

• Adjust chromaticity (decoherence), tune, orbit, coupling

Step A.3.6: (3 х 10¹⁰) Establish cycling machine [2 rings separate]

1. Without beam

   1. Test sequence for cycling machine and programmed dump at injection plateau

2. With beam (first attempt with pilot intensity, after success resume with 3 x 10¹⁰)

   1. Verify reproducibility of orbit (also energy matching)

      1. RMS, maxima

      2. at injection point

   2. Verify reproducibility of loss patterns during injection

   3. Verify reproducibility of lifetime

Step A.3.7: (3 х 10¹⁰): Further commissioning of beam instrumentation with lifetime > 1hr [2 rings separate]

1. Systematic BPM & corrector calibration: ring1, ring2, YASP

   1. Scan all orbit correctors and acquire all monitors - polarity and calibration

      • 30 s per COD (530 CODs per plane)

   2. Check response data for BPM/COD polarities and calibrations

   3. Flatten orbit in injection regions and dumping region

   4. Use response data for  linear optics check: LOCO [1]

      • phase advance, beta, coupling

      • use trajectory data, not only orbit data

   5.  BPMs and correctors in common sections

2. Commission PLL tune & coupling measurement

3. Commission wire scanners

   1. may need to slow them down to get desired resolution on single bunch

      • 2 m per second → 180 micron per point

   2. Cross-calibrate with the SPS

4. Commission synchrotron light monitors

   1. Commission undulators (priority 1)

   2. (pilot intensity) Commission abort gap monitor (BSRA) (priority 1)

      1. Change gate of BSRA over injection bucket to have enough intensity

      2. Commission optics - will require tunnel intervention for fine adjustment

      3. Calibrate photon production versus proton number

      4. If interlocked: set interlock threshold: 10 % of quench limit in p⁺/m

      5. Check timing (gate over abort gap)

   3. Commission synchrotron light beam size monitor (priority 2) - can be done parasitically, running continuously

5. Commission rest gas ionisation monitor

   1. Commission gas injection system

   2. Optional: checks of signal for different injected emittances, beam position, stability etc.

    

Step A.3.8:  (3 х 10¹⁰): Basic optics checks in addition to LOCO results and optimisation ([5]) [2 rings separate]

1. Acquire multi-turn data for harmonic analysis → phase

   1. Generate oscillations by mis-steering injection (note aperture limit in MSI)

   2. Optional: use MKQ for excitation

   3. Evaluate beta functions at dump elements in IR6 and for MSI, TDI, TCDD, transverse damper (Q7, Q9, dampers)

      1. Store in database (needed for setting of absorbers)

   4. Rough estimation of beta function at wires

      1. Store in database (needed for emittance measurement)

   5. Check reproducibility after cycling

2. Measure emittance (wire scanner)

   1. Store in database for collimators

   2. Check reproducibility after cycling

3. RF tuning:

   • Observe 400 MHz component of bunch intensity (BCTDC) vs. time to optimise the machting voltage: bunch phase module

   • Deduce longitudinal losses

   • Measure longitudinal profile and bunch length vs. time (RF: scope in SR4, CCC: mountain range/OASIS)

Step A.3.9: (3 х 10¹⁰): Further commissioning of beam dumping system [2 rings separate]

1. With circulating beam:

   1. First checks of beam stability and settings at TCDQ elements - SW interlock tests

   2. First checks of TCDQ-beam positioning stability and protection (see details of procedure here [2])

   3. Check beam dependent HW interlocks (orbit in IR6, direct BLM on TCDQ) ↔ MCS for BPM;

   4. Measure aperture with circulating beam

      • H: TCDS entrance, MSD exit, TCDQ, TCS

      • H&V: MKD, MSD, TCDQM (retract TCDQ)

   5. Check reproducibility of orbit in point 6, re-check part of the apertures

   6. Sequence circulate & dump: (pilot intensity) check abort gap watchdog with beam:

      • TDI needs to be in (~ 10 sigma)

      • Try to inject bunch into forbidden buckets: should end up on the TDI

        • Scan forbidden RF buckets

2. With extracted beam: sequence circulate & dump (inject & dump also possible if needed)

   1. Measure extraction trajectory and extraction line aperture

      • H aperture: TCDS, MSD exit using closed orbit bumps to displace beam

      • Check explicitly that aperture is adequate for 14/15 MKD - steer orbit in IR6 (cannot unplug 1 MKD). Need to change orbit angle by 270 / 15 urad. Beware of BPM interlock!

   2. Check IPOC, logging, fixed displays, PM, XPOC ([6])

   3. Check thermal response of TDE

   4. (pilot intensity): Adjust fine kicker timing with 2 pilots  (bunch 1 & 2808) to define abort gap. Note UA access needed for each trim (power of mains can stay on).

   5. TD line aperture and MKD and MKB sweep waveform overshoot measurements by changing injected bunch number: ~20 initial points.

   6. Check reproducibility using XPOC data

    

Step A.3.10: (3 х 10¹⁰): Commission feedback systems (needs sufficient life time) [2 rings separate]

1. Commission RF radial loop [7]:

   1. Switch from synchro to radial loop after injection transient (synchro loop off)

   2. Commission radial pick-up electronics and digital acquisition

   3. Displace beam with radial steering (OP)

   4. Apply a step to measure radial loop response (RF)

   5. Optimise loop dynamics - gains (RF)

   6. Rough estimation of dispersion at the wires

      1. Store in database to update optics information for emittance measurement

      2. Measure emittance

2. Commission transverse feedback equipment

   1. Commission damper pick-ups

      1. Verify signal levels in BPMCs (damper pick-ups) versus transverse bunch position (calibrate with orbit BPMs)

      2. Equalize delay of BPMCs from Q7 and Q9 locations (needs local adjustment at SR4)

   2. Commission RF front-end of damper

      1. Required: stable tune, phase advance known Q7->Q9->damper (both planes, both beams); beta functions known at Q7, Q9, dampers

      2. Generate injection oscillations (mis-steering injection), check available damper kick strength

      3. Commission analog front-end

      4. Commission digitization and f_rev tagging for bunch

3. Commission RF radial modulation

4. Commission continuous chromaticity measurement

   1. Requires RF modulation to be operational ( ~ 1 Hz modulation)

   2. Optimise PLL to track tune modulation

5. Commission orbit feedback

   1. Use "best guess" optics model, as far as measured

   2. Operate with a low effective closed loop bandwidth (e.g. 0.1 Hz)

   3. Check at critical locations (TDI, TCDQ). SW interlock tolerances to be defined.

6. Commission tune & coupling feedback with PLL

   1. Verify trim quadrupole calibration (16 circuits per beam) if not done already

   2. Verify trim skew quadrupole calibration (12 circuits B1 & 10 circuits B2) if not done already

      • robust tune feedback needs coupling correction → commissioning tunes should help: 64.285/59.385

   3. Operate with a low effective closed loop bandwidth

Step A.3.11: (3 х 10¹⁰): Rough setting up of TDI [2 rings separate]

1. First checks of feedback and stability at TDI

   1. Mode: circulate & dump

   2. Lock the orbit with orbit feedback

   3. Measure stability and reproducibility

2. Verify the centering of the TDI with circulating beam

   1. Mask BLM thresholds at TDI

   2. Centre TDI jaws with beam

   3. Unmask BLMs

3. Optional: verify alignment of TDI with respect to trajectory/orbit:  

   1. Inject & dump with BCTFR in IR4 → would have to be redone with circulating beam

   2. Or: circulate & dump, BLM signals at TDI and BCT readings [8]

4. Set TDI to 10 sigma with the measured information

   • Optional: take beam envelope into account if difference between nominal beam size at upstream and downstream end large