Conceptual design of the SPL II: A high-power superconducting H−H^- linac at CERN

An analysis of the revised physics needs and recent progress in the technology of superconducting RF cavities have led to major changes in the speci cation and in the design for a Superconducting Proton Linac (SPL) at CERN. Compared with the rst conceptual design report (CERN 2000012) the beam energy is almost doubled (3.5 GeV instead of 2.2 GeV), while the length of the linac is reduced by 40% and the repetition rate is reduced to 50 Hz. The basic beam power is at a level of 45MW and the approach chosen offers enough margins for upgrades. With this high beam power, the SPL can be the proton driver for an ISOL-type radioactive ion beam facility of the next generation (`EURISOL'), and for a neutrino facility based on superbeam C beta-beam or on muon decay in a storage ring (`neutrino factory'). The SPL can also replace the Linac2 and PS Booster in the low-energy part of the CERN proton accelerator complex, improving signi cantly the beam performance in terms of brightness and intensity for the bene t of all users including the LHC and its luminosity upgrade. Decommissioned LEP klystrons and RF equipment are used to provide RF power at a frequency of 352.2 MHz in the lowenergy part of the accelerator. Beyond 90 MeV, the RF frequency is doubled to take advantage of more compact normal-conducting accelerating structures up to an energy of 180 MeV. From there, state-ofthe- art, high-gradient, bulk-niobium superconducting cavities accelerate the beam up to its nal energy of 3.5 GeV. The overall design approach is presented, together with the progress that has been achieved since the publication of the rst conceptual design report

The SPL (II) at CERN, a Superconducting 3.5 GeV H- Linac

A revision of the physics needs and recent progress in the technology of superconducting (SC) RF cavities have triggered major changes in the design of a SC H-linac at CERN. With up to 5MW beam power, the SPL can be the proton driver for a next generation ISOL-type radioactive beam facility (âEURISOLâ) and/or supply protons to a neutrino () facility (conventional superbeam + beta-beam or -factory). Furthermore the SPL can replace Linac2 and the PS booster (PSB), improving significantly the beam performance in terms of brightness, intensity, and reliability for the benefit of all proton users at CERN, including LHC and its luminosity upgrade. Compared with the first conceptual design, the beam energy is almost doubled (3.5GeV instead of 2.2 GeV) while the length is reduced by 40%. At a repetition rate of 50 Hz, the linac reuses decommissioned 352.2MHz RF equipment from LEP in the low-energy part. Beyond 90MeV the RF frequency is doubled, and from 180MeV onwards high-gradient SC bulkniobium cavities accelerate the beam to its final energy of 3.5GeV. This paper presents the overall design approach, together with the technical progress since the first conceptual design in 2000

Design of a Side-Coupled Linear Accelerator Structure for Linac4

In Linac 4, proposed as a future H¯ linear accelerator for CERN, a Side-Coupled Linac (SCL) structure will accelerate the beam from 90 MeV to 160 MeV. This note presents the preliminary SCL design, including 2D and 3D RF structure design, layout optimisation, setting up of matched beam optics parameters and a multiparticle beam dynamics analysis

Beam Dynamics for a New 160 MeV H−H^{-} Linac at CERN (LINAC4)

Linac4 is a normal conducting H- linac proposed at CERN to provide a higher proton flux to the CERN accelerator chain. It should replace the existing Linac2 as injector for the PS booster (PSB). The same machine can also operate in the future as the front end of the SPL, a 2.2 GeV superconducting linac with 1.8 mA average current. At present Linac4 consists of a Radio Frequency Quadrupole (RFQ), a chopper line, a Drift Tube Linac (DTL), and Cell Coupled DTL (CCDTL) all operating at 352.2 MHz and finally a Side Coupled Linac (SCL) at 704.4 MHz. This paper discusses the overall beam dynamics concept, presents the optics for the different sections of the machine and compares end-to-end simulations realised with two tracking codes (PATH and IMPACT). The influence of phase/energy errors is discussed and the challenging features in the current design are highlighted

EU contract number RII3-CT-2003-506395 CARE Conf-04-014-HIPPI

This paper discusses the overall beam dynamics concept, presents the optics for the different sections of the machine and compares end-to-end simulations realised with two tracking codes (PATH and IMPACT). The influence of phase/energy errors is discussed and the challenging features in the current design are highlighte