New scheme with Linac4 increase bunch density in the PSB by a factor 2, in order to: Make nominal LHC beam in single batch (simpler operation).
Present scheme LHC nominal beam in PS with 3x1x2 PSB bunches (3 rings x 1 bunch x 2 batches), at the limit of what can be achieved by the injectors ( ppb). Structures and klystrons dimensioned for 50 Hz Power supplies and electronics dimensioned for 2 Hz, 1.2 ms pulse.īottleneck for higher brightness at PSB injection: Incoherent space charge tune shift dominates injection process. Chopping at low energy to reduce beam loss at PSB.
rate for accelerating structures 50 Hz Re-use 352 MHz LEP RF components: klystrons, waveguides, circulators. particles per pulseđ.0 × 1014 Transverse emittanceĐ.4 p mm mrad Max. Beam Duty Cycle % Chopper Beam-on FactorĖ5 % Chopping scheme: 222 transmitted /133 empty buckets Source current 80 mA RFQ output currentė0 mA Linac pulse currentĔ0 mA N. Ion species H− Output Energy 160 MeV Bunch Frequency MHz Max. H− particles + higher injection energy (160/50 MeV, factor 2 in bg2) same tune shift in PSB with twice the intensity. Space provided at the end of the linac for the connection to the SPLĥ Linac4 Parameters Ion species H− Output Energy 160 MeV Power supplies, electronics and infrastructure (water, electricity) dimensioned only for low beam power operation (PSB, LP-SPL). Accelerating structures and klystrons dimensioned for high duty operation.
THE 50S IPHI UPGRADE
Injector to Low Power-SPL (2018- ?): Hz, 20 mA, 1.2 ms only minor upgrade (few power supplies) Injector to High Power-SPL (>2020 ?): Hz, 40 mA, 1.2 ms max important upgrade (RF modulators, power supplies, cooling, etc.) Main consequences on the design: Shielding dimensioned for the SPL high beam power operation (1 W/m beam loss). Linac4 is designed to operate in 3 different modes: Injector to PS Booster ( ?): Hz, 40 mA, 400 ms.
THE 50S IPHI PS2
PS PSB PS2 - SPS Transfer line Future SPL Present 50 MeV Linac2 Linac4 Position and orientation allow a future extension to the SPL. It will be built at the place of “Mount Citron”, made in the 50’s with the excavation materials of the PS. Linac4 will replace Linac2 (50 MeV) as injector to the PSB. To understand the present, we need to know the pastģ Linac4 on the CERN site PS PSB PS2 - SPS Transfer line Future SPL Approval of White Paper by CERN Council (June). 2007: define a new location for Linac4, permitting extension to LP (Low-power)-SPL. Linac4 Technical Design Report issued December 2006. 2006: first draft of “White Paper”, including Linac4 construction in the frame of LHC Upgrade plans. Agreements with France (IPHI RFQ) and with ISTC (prototypes in Russia). 2003: energy up to 160 MeV, called “Linac4” (4th linac to be built at CERN) 2004: start Linac4 R&D, - started CARE Activity on high-intensity linacs (HIPPI), for ( ). 2001: idea to build in a first stage the warm part of the SPL (120 MeV) in the old PS South Hall and use it to inject H− into the PSB, improving the beam brightness in the PS complex. HHH Workshop – 1st step into the post-LHC eraġ996: first proposal of a Superconducting Proton Linac (SPL) at CERN, using the LEP accelerating system (cavities + RF) for a high power linac, with injection into the PS at 2 GeV. Vretenar for the Linac4 design team"- Presentation transcript:ġ Linac4 M.
0 kommentar(er)
