LHC PIC performance and aspects related to the injectors G. Arduini with input from O. Brüning, R. De Maria, S. Fartoukh, P. Fessia, S. Gilardoni, B. Gorini, L. Rossi, G. Rumolo, R. Tomàs
Main Hardware changes: being finalized PIC • New TAS, 60 mm, IT, D1, 150 mm, correctors • New collimatorswith buttons, new materialsfor robustness and impedance, new TCTs in IR1-5 for D2-Q5 for cleaning and protection • Arc sextupoles (MS) at 600A • SC links in IR15, QRL • New poweringwith SC links at P7 (RR) • New Cryoplant P4 for SCRF • Cryoplants in P1,5 • Beampipes and Y chamberbetween D1 and TAN3
LHC Injection to Collisions • 5% intensity loss assumed • 20% emittance blow-up budget, implies: • Control of the additive sources of blow-up • Control of the blow-up due to electron clouds (successful scrubbing in the dipoles) • Impedance reduction with metallic collimators
Assumptions for the performance estimates • Average pile-up limitin IP1-5: • 140 evt per crossing; • 1.4 evt/mm accepted but 0.7 evt/mm shouldbe the target; • Burn-off and pile-up estimation based on: • Assumed visible cross-section: 85 mb; • Assumed total cross-section: 100 mb; • Emittanceevolutionincluding: • IBS • Radiation damping • Can representprettywell performance in 2012 (when no instabilitesobserved). Onlyunknownlifetime component is >100 h.
PIC @ 6.5 TeV (Pile-up limit at 140) • b*=40/20 cm could be relaxed to gain aperture and reduce pile-up density (e.g. 50/25 - S. Fartoukh) with little loss in integrated luminosity. • Required beam-beam separation being finalized (13 sigmas might be preferable with flat beams)
Some Conclusions • Significant margin: possibility to produce up to 120 fb-1/year but • Pile-up is the stronger limitation for the performance • BCMS and Standard production schemes give similar performance