IPAC2012 - List of Authors (Ostiguy, J.-F.)

Paper	Title	Page
TUPPC010	Study of Effects of Failure of Beamline Elements and its Compensation in CW Superconducting Linac	1173
	A. Saini, K. Ranjan University of Delhi, Delhi, India C.S. Mishra, J.-F. Ostiguy, N. Solyak, V.P. Yakovlev Fermilab, Batavia, USA
	Project-X is the proposed high intensity proton facility to be built at Fermilab in United States. First stage of the Project-X consists of H^- superconducting linac (SC) which will be operated in continuous wave (CW) mode to accelerate the beam from kinetic energy of 2.1 MeV to 3 GeV. The operation in CW mode puts stringent tolerances on the beam line components, particularly at low energy section. The failure of beam line elements result in mismatch of the beam with the following sections due to different beam parameters than designed parameters. It makes the beam unstable which causes emittance dilution, and ultimately results in beam losses. In worst case, it can affect the reliability of the machine and may lead to the shutdown of the linac to replace the failed elements. Thus, it is important to study impacts of these effects and their compensation to restore linac performance to avoid beam interruption. This paper presents the studies performed for the failure of accelerating cavity and focusing magnets at the critical locations in the Project-X CW superconducting linac

WEPPC044	Multipole Effects Study for Project X Front End Cavities	2309
	P. Berrutti, M.H. Awida, I.V. Gonin, J.-F. Ostiguy, N. Solyak, V.P. Yakovlev Fermilab, Batavia, USA
	Effects of RF field asymmetry along with multipoles have been studied in Project X front end cavities. One family of half wave resonators operating at 162.5 and two of spoke resonators operating at 325 MHz have been analysed. HWR and spoke resonators unlike elliptical cavities, do not have axial symmetry, hence a quadrupole perturbation to the beam is present. The purpose of this paper is to explain the approach and the calculation method used to understand and overcome the drawbacks due to the RF field asymmetry.

THPPP056	Beam Loss Due to Misalignments, RF Jitter and Mismatch in the Fermilab Project-X 3GeV CW Linac	3868
	J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, J.-F. Ostiguy, A. Saini, B.G. Shteynas, N. Solyak Fermilab, Batavia, USA
	This paper presents an analysis of beam losses along the current design of the FNAL 3 GeV superconducting cw linac. Simulations from the RFQ exit up to the end of the linac (~430 meters) are performed on the FermiGrid using the beam dynamics code TRACK. The impact of beam mismatch, element misalignments, and RF jitter on the beam dynamics is discussed and corresponding beam loss patterns are presented. A correction scheme to compensate for misalignments is described.

THPPP057	PXIE Optics and Layout	3871
	V.A. Lebedev, S. Nagaitsev, J.-F. Ostiguy, A.V. Shemyakin, B.G. Shteynas, N. Solyak Fermilab, Batavia, USA
	The Project X Injector Experiment (PXIE) will serve as a prototype for the Project X front end. The aim is to validate the Project-X design and to decrease technical risks, known to be mainly related to the front end. PXIE will accelerate a 1 mA CW beam to about 25 MeV. It will consist of an ion source, LEBT, CW RFQ, MEBT, two SC cryomodules, a diagnostic section and a beam dump. A bunch-by-bunch chopper located in the MEBT section will allow formation of an arbitrary bunch structure. PXIE deviates somewhat from the current Project-X front end concept in that it provides additional instrumentation and relies on a reduced number of kickers for bunch chopping; the diagnostic section also include an RF separator to allow studying extinction of removed bunches. The paper discusses the main requirements and constraints motivating the facility layout and optics. Final adjustments to the Project X front end design, if needed, will be based on operational experience gained with PXIE. Operated by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.

THPPP091	Status of the Project-X CW Linac Design	3948
	J.-F. Ostiguy, P. Berrutti, J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, A. Saini, B.G. Shteynas, N. Solyak, V.P. Yakovlev Fermilab, Batavia, USA
	Superconducting CW linac was proposed for Project X to accelerate H⁻ beam from 2.1 MeV to 3 GeV with nominal peak and average currents of respectively 5 mA and 1 mA. Linac built of 5 different families of resonators: half-wave, spoke (2), and elliptical (2) working at 162.5 MHz 325 MHz and 650 MHz to cover all energy range. Cavities and focusing elements are assembled in cryomodules. In baseline design all cryomodules are separated by short warm sections. It makes machine more reliable and maintainable and provide space for beam diagnostics and collimation. A long (~10m) gap between cryomodules at1 GeV is also being considered to provide space for beam extraction for nuclear experimental program. In paper we present the latest lattice of the linac baseline design and results of beam studies for this lattice. We briefly compare performance of the baseline design with alternative one without half-wave resonator section.

Paper

Title

Page

Study of Effects of Failure of Beamline Elements and its Compensation in CW Superconducting Linac

1173

A. Saini, K. Ranjan
University of Delhi, Delhi, India
C.S. Mishra, J.-F. Ostiguy, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, USA

Project-X is the proposed high intensity proton facility to be built at Fermilab in United States. First stage of the Project-X consists of H^- superconducting linac (SC) which will be operated in continuous wave (CW) mode to accelerate the beam from kinetic energy of 2.1 MeV to 3 GeV. The operation in CW mode puts stringent tolerances on the beam line components, particularly at low energy section. The failure of beam line elements result in mismatch of the beam with the following sections due to different beam parameters than designed parameters. It makes the beam unstable which causes emittance dilution, and ultimately results in beam losses. In worst case, it can affect the reliability of the machine and may lead to the shutdown of the linac to replace the failed elements. Thus, it is important to study impacts of these effects and their compensation to restore linac performance to avoid beam interruption. This paper presents the studies performed for the failure of accelerating cavity and focusing magnets at the critical locations in the Project-X CW superconducting linac

WEPPC044

Multipole Effects Study for Project X Front End Cavities

2309

P. Berrutti, M.H. Awida, I.V. Gonin, J.-F. Ostiguy, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, USA

Effects of RF field asymmetry along with multipoles have been studied in Project X front end cavities. One family of half wave resonators operating at 162.5 and two of spoke resonators operating at 325 MHz have been analysed. HWR and spoke resonators unlike elliptical cavities, do not have axial symmetry, hence a quadrupole perturbation to the beam is present. The purpose of this paper is to explain the approach and the calculation method used to understand and overcome the drawbacks due to the RF field asymmetry.

THPPP056

Beam Loss Due to Misalignments, RF Jitter and Mismatch in the Fermilab Project-X 3GeV CW Linac

3868

J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, J.-F. Ostiguy, A. Saini, B.G. Shteynas, N. Solyak
Fermilab, Batavia, USA

This paper presents an analysis of beam losses along the current design of the FNAL 3 GeV superconducting cw linac. Simulations from the RFQ exit up to the end of the linac (~430 meters) are performed on the FermiGrid using the beam dynamics code TRACK. The impact of beam mismatch, element misalignments, and RF jitter on the beam dynamics is discussed and corresponding beam loss patterns are presented. A correction scheme to compensate for misalignments is described.

THPPP057

PXIE Optics and Layout

3871

V.A. Lebedev, S. Nagaitsev, J.-F. Ostiguy, A.V. Shemyakin, B.G. Shteynas, N. Solyak
Fermilab, Batavia, USA

The Project X Injector Experiment (PXIE) will serve as a prototype for the Project X front end. The aim is to validate the Project-X design and to decrease technical risks, known to be mainly related to the front end. PXIE will accelerate a 1 mA CW beam to about 25 MeV. It will consist of an ion source, LEBT, CW RFQ, MEBT, two SC cryomodules, a diagnostic section and a beam dump. A bunch-by-bunch chopper located in the MEBT section will allow formation of an arbitrary bunch structure. PXIE deviates somewhat from the current Project-X front end concept in that it provides additional instrumentation and relies on a reduced number of kickers for bunch chopping; the diagnostic section also include an RF separator to allow studying extinction of removed bunches. The paper discusses the main requirements and constraints motivating the facility layout and optics. Final adjustments to the Project X front end design, if needed, will be based on operational experience gained with PXIE.
Operated by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.

THPPP091

Status of the Project-X CW Linac Design

3948

J.-F. Ostiguy, P. Berrutti, J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, A. Saini, B.G. Shteynas, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, USA

Superconducting CW linac was proposed for Project X to accelerate H⁻ beam from 2.1 MeV to 3 GeV with nominal peak and average currents of respectively 5 mA and 1 mA. Linac built of 5 different families of resonators: half-wave, spoke (2), and elliptical (2) working at 162.5 MHz 325 MHz and 650 MHz to cover all energy range. Cavities and focusing elements are assembled in cryomodules. In baseline design all cryomodules are separated by short warm sections. It makes machine more reliable and maintainable and provide space for beam diagnostics and collimation. A long (~10m) gap between cryomodules at1 GeV is also being considered to provide space for beam extraction for nuclear experimental program. In paper we present the latest lattice of the linac baseline design and results of beam studies for this lattice. We briefly compare performance of the baseline design with alternative one without half-wave resonator section.