Beam tests
Pilot Beam for the most part:
- Single bunch
- Intensity: 5 to 10 x 109 protons per bunch
- Below quench limit if loss over > 5 m.
- 2 orders of magnitude below damage threshold.
To be used with two main stipulations: don’t irradiate Alice, and don’t
irradiate the rest of the ring too much. The clear aim will be to minimise
losses and use beam sparingly when we know where it’s going. There will be zero
crossing angle in Alice which opens the local aperture considerably.
Main goals of test:
- Commission injection system: final part of TI2, septa, kickers and
TDI. Check stability of transfer lines and ability to steer injection point.
Commission screens. Beam to TDI.
- Commission Beam Loss Monitor system see below
- Commission trajectory acquisition and correction. Thread beam to
dump. Check all related beam instrumentation: BLMs, BPMs (polarity,
offsets). This will
be the first, provisional check of the aperture. Check energy
matching. [Need TI2/LHC continuous sequence]
- Linear optics checks: check trajectory versus kick, phase advance,
BPM and corrector polarity. Coupling. Matching between TI2 and sector. Determination
of Twiss functions. Need to establish standard procedure to identify and
correct all local sources of phase advance errors.
- Mechanical aperture checks. Bumps - check the aperture in the cold machine is free and has the expected size.
- Field quality checks. Check design fields, field harmonics, fields due to offsets
between beam and magnet.
- Test control and correction (corrector polarity, cabling, control
system, software, procedures, …).
- Hardware exposure to beam will allow first reality checks of assumptions
of quench limits and the like.
Proposed tests