W.Venturini / M.Solfaroli

1. Preparation for Ions in LHC • CONTENT: • Beam characteristics and MP concerns • BI configuration • Operational settings • Collimators • Planning • Shift breakdown Thanks to: P.Baudrenghien, G.Bellodi, B.Goddard, J.J.Gras, D.Jacquet, J.Jowett, M.Lamont, S.Redaelli, F.Roncarolo, M.Sapinsky, R.Steinhagen W.Venturini / M.Solfaroli

2. Beam Characteristics • Bunch intensity = 7x107 ions (5.74 x109 charges/bunch) • Squeezed to 3.5m • Transverse normalized emittance ~1.5/0.8 μm (nominal/used, for the same beam size as for protons) • First setup with 2 bunches/beam (still safe beam @3.5TeV) and collisions in all IPs • Nominal filling scheme (128b) for luminosity production being finalized (see J.Jowett’s slides) • Energy of the nominal beam (128b) ~400kJ • Possibility of quench in the DSs negligible with this intensity • SBF reduction factor still to be decided. Proposal for 2 or 2.5 as it’s the maximum we can do while keeping safe beam measurable (2b beam still safe @3.5TeV) W.Venturini - M.Solfaroli

3. Beam Instrumentation W.Venturini - M.Solfaroli

4. Settings management • Ramp and Squeeze functions are ready in a dedicated Hypercycle(EARLY-IONS_3.5TeV) • Most settings identical to protons but: • RF ( functions are ready) • Xing angles in collisions • Collimation • To minimize the changes, Xing settings maintained as for p throughout INJECTION, RAMP and SQUEEZE: • Xing angle to be set at: • 0 μrad for IP1 and IP5 • -140 μrad (external angle) for IP2. As ALICE wants to flip the spectrometer polarity during the run the external angle will be later set at +140 μrad • Same Xing angle as for protons and parallel separation for IP8 (no collision required) W.Venturini - M.Solfaroli

5. Collimation system (I) • If possible, no changes to IP7 and IP3 settings all over the cycle • Cross calibration of orbit reading with protons: • Inject high intensity p bunch (LOW BPM sensitivity) • Correct against reference orbit • Inject low intensity p bunch and record orbit (HIGH BPM sensitivity) • Inject an Ions bunch and check that orbit is the same • Define it as Ions reference orbit • Test ramp with safe Ions beam (2b), collimators at injection settings and OFB on to establish reference orbit up to high energy • During squeeze use same orbit reference as for protons and measure the optics W.Venturini - M.Solfaroli

6. Collimation system (II) • Subsequent ramp with the same collimator settings as for p till the end of the squeeze, then: • Keep IP8 separation and Xing angle • Change Xing angles as required in IP1, IP2 and IP5 • Set-up of TCTs around new collision orbit • As a result only one collimator set-up to be done at top energy • Loss maps: • done in 5 configuration for p • Suggested a minimum of 3 (~4 fills) for Ions @: • Injection • End of squeeze • Collisions • SHADOWING OF ZDC…OPEN PROBLEM – to MPP W.Venturini - M.Solfaroli

7. Planning <<We’ll be starting with a machine that already does the equivalent with protons so we should be able to run through many procedures smoothly>> W.Venturini - M.Solfaroli

8. Shift Breakdownfrom start to first collisions J.Jowet W.Venturini - M.Solfaroli

9. Shift Breakdownfrom start to first collisions J.Jowet W.Venturini - M.Solfaroli

10. Open questions • Transverse emittance: • as low as possible? 0.8 μm? • ADT off? • Longitudinal emittance: • start without blow-up (in case of need it should be ready (Philippe B.)) • Re-steering of transfer lines? • LBDS - special tests? • Loss maps configuration to be decided • Shadowing of ZDC…OPEN PROBLEM – to MPP • LHCb dipole and compensator off? W.Venturini - M.Solfaroli