IPAC2012 - List of Authors (Solyak, N.)

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

TUPPP092	Renovated Two-stage Bunch Compressor for the International Linear Collider	1801
	S. Seletskiy BNL, Upton, Long Island, New York, USA N. Solyak Fermilab, Batavia, USA
	The International Linear Collider (ILC) utilizes a Bunch Compressor (BC) in the Damping Ring to Main Linac Transfer Line (RTML) that compresses the RMS bunch length from 6 mm to 300 micrometers before sending the beam to the Main Linac. It was decided to utilize a two stage BC for the design baseline, since it provides an additional option for the ILC to work with 150 micrometers long bunches and reduces the energy spread at the RTML exit under normal operational conditions. In this paper we report the new design of the optimized two-stage bunch compressor.

TUPPR043	New Baseline Design of the ILC RTML System	1915
	N. Solyak, V.V. Kapin, A. Vivoli Fermilab, Batavia, USA S. Seletskiy BNL, Upton, Long Island, New York, USA
	The new ILC baseline was proposed in 2009 (Strawman baseline - SB2009) to minimize cost of the machine and accommodate many changes made in the design of the accelerator systems. The biggest changes are made in the central area, where BDS, RTML, DR, electron and positron sources are sharing the tunnels. A new layout of the compact DR and re-location of the electron and positron sources to the main tunnel requires a new lattice design for all beamlines in this area. The lattice design was coordinated between accelerator systems and Convention Facility and Siting (CFS) group to eliminate conflicts between beamlines and satisfy construction requirements. In this paper we present a new design of the RTML electron and positron lattices in the central area and other modifications made in the RTML line to accommodate changes to the beamline layouts.

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.

WEPPC045	Optimization of the Geometric Beta for the SSR2 Cavities of the Project X	2312
	P. Berrutti, M.H. Awida, I.V. Gonin, N. Solyak, A. Vostrikov, V.P. Yakovlev Fermilab, Batavia, USA
	Project X based on the 3 GeV CW superconducting Linac and is currently in the R&D phase. The cw SC Linac starts from a low-energy SCRF section (2.1 - 165 MeV) containing three different types of resonators. HWR f=162.5 MHz (2.1 - 11 MeV) having β= 0.11, SSR1 f= 325 MHz (11 - 35 MeV) having β = 0.21. In this paper we present the analysis that lead to the final design of SSR2 f=325 MHz cavity (35 - 165 MeV). We present the results of optimization of the geometric beta and the comparison between single, double and triple spoke resonators used in Project X frontend.

WEPPC047	Effects of the RF Field Asymmetry in SC Cavities of the Project X	2318
	I.V. Gonin, M.H. Awida, P. Berrutti, A. Saini, B.G. Shteynas, N. Solyak, V.P. Yakovlev Fermilab, Batavia, USA P.N. Ostroumov ANL, Argonne, USA
	The low-energy SCRF section of CW SC linac of Project X starts from Half Wave Resonators (HWR) having operating frequency f=162.5 MHz, optimal β= 0.11 and will accelerate the beam from 2 MeV up to 11 MeV. The preliminary analysis of beam dynamics shows that multipole effects caused by asymmetry of RF fields in HWR cavities aren’t negligible. In this paper we present the analysis of influence of multipole effects on beam dynamics and discuss the possible solutions how to compensate these effects.

WEPPC054	Resonance Excitation of Longitudinal High Order Modes in Project X Linac	2336
	A.I. Sukhanov, M.H. Awida, I.V. Gonin, T.N. Khabiboulline, A. Lunin, N. Solyak, V.P. Yakovlev Fermilab, Batavia, USA
	Results of simulation of power loss due to excitation of longitudinal high order modes (HOMs) in the accelerating superconducting RF system of CW linac of Project X are presented. Beam structures corresponding to the various modes of Project X operation are considered: CW regime for 3 GeV physics program; pulsed mode for neutrino experiments; and pulsed regime, when Project X linac operates as a driver for Neutrino Factory/Muon Collider. Power loss and associated heat load due to resonance excitation of longitudinal HOMs are shown to be small in all modes of operation. Conclusion is made that HOM couplers can be removed from the design of superconducting RF cavities of Project X linac.

WEPPC059	A Two-stage Injection-locked Magnetron for Accelerators with Superconducting Cavities	2348
	G.M. Kazakevich, G. Flanagan, R.P. Johnson, F. Marhauser, M.L. Neubauer Muons, Inc, Batavia, USA B. Chase, S. Nagaitsev, R.J. Pasquinelli, N. Solyak, V. Tupikov, D. Wolff, V.P. Yakovlev Fermilab, Batavia, USA
	Funding: Supported in part by SBIR Grant 4743 11SC06261 A concept for a two-stage injection-locked CW magnetron intended to drive Superconducting Cavities (SC) for intensity-frontier accelerators has been proposed. The concept is based on a theoretical model that considers a magnetron as a forced oscillator; the model has been experimentally verified with a 2.5 MW pulsed magnetron. The two-stage CW magnetron can be used as a RF power source for Fermilab’s Project-X to feed separately each of the SC of the 8 GeV pulsed linac. For Project-X the 1.3 GHz two-stage magnetron with output power of 20-25 kW and expected output/input power ratio of about 35-40 dB would operate in a quasi-CW mode with a pulse duration ≤ 10 ms and repetition rate of 10 Hz. The magnetrons for both stages should be based on the commercial prototypes to decrease the cost of the system. An experimental model of the two-stage CW S-band magnetron with peak power of 1 kW, with pulse duration of 1-10 ms, has been developed and built for study. A description of the theoretical and experimental models, simulations, and experimental results are presented and discussed in this work.

WEPPD035	Design Considerations for an MEBT Chopper Absorber of 2.1MeV H⁻ at the Project X Injector Experiment at Fermilab	2585
	C.M. Baffes, M.H. Awida, A.Z. Chen, Y.I. Eidelman, V.A. Lebedev, L.R. Prost, A.V. Shemyakin, N. Solyak, V.P. Yakovlev Fermilab, Batavia, USA
	Funding: Operated by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the United States Department of Energy The Project X Injector Experiment (PXIE) will be a prototype of the Project X front end that will be used to validate the design concept and decrease technical risks. One of the most challenging components of PXIE is the wide-band chopping system of the Medium Energy Beam Transport (MEBT) section, which will form an arbitrary bunch pattern from the initially CW 162.5 MHz 5mA beam. The present scenario assumes diverting 80% of the beam to an absorber to provide a beam with the average current of 1mA to SRF linac. This absorber must withstand a high level of energy deposition and high ion fluence, while being positioned in proximity of the superconductive cavities. This paper discusses design considerations for the absorber, including specific challenges as spreading of energy deposition, management of temperatures and temperature-induced mechanical stresses, radiation effects, surface effects (sputtering and blistering), and maintaining vacuum quality. Thermal and mechanical analyses of a conceptual design are presented, and future plans for the fabrication and testing of a prototype are described.

WEPPD058	The Project-X 3 GeV Beam Distribution System	2651
	D.E. Johnson, M.H. Awida, M.S. Champion, I.V. Gonin, A.L. Klebaner, N. Solyak, V.P. Yakovlev Fermilab, Batavia, USA
	In the Project X facility, a 3 GeV H⁻ CW beam is delivered to three users simultaneously. This will be accomplished by selectively filling appropriate RF buckets at the front end of the linac and then utilizing a RF splitter to transversely separate bunches to three different target halls. A compact TE113 squashed-wall superconducting RF cavity has been proposed to produce the initial vertical deflection. The transport line optics, cavity design parameters, and cryogenic system requirements will be presented.

WEPPR029	Alternative Cavity for H E Part of the Project X linac	2997
	A. Lunin, A. Saini, N. Solyak, A.I. Sukhanov, V.P. Yakovlev Fermilab, Batavia, USA
	An alternative superconducting elliptical cavity is suggested for High Energy (HE) part of the Project X linac. The cavity is suitable to operate at CW regime with high beam current (10 mA), which is critical for Accelerator-Driven Subcritical (ADS) systems and for intense muon source for future Neutrino Factory or Muon Collider. We present the algorithm of the cavity shape optimization, comprehensive tolerances analysis and the solution for monopole High Order Modes (HOM) damping. Based on these results we estimated the probabilities of cryogenic losses per cryomodule and a growth of the beam longitudinal emittance due to the resonance excitation of monopole HOMs in the HE linac for Project X.

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.

THPPP058	PXIE: Project X Injector Experiment	3874
	S. Nagaitsev, S.D. Holmes, R.D. Kephart, J.S. Kerby, V.A. Lebedev, C.S. Mishra, A.V. Shemyakin, N. Solyak, R.P. Stanek Fermilab, Batavia, USA D. Li LBNL, Berkeley, California, USA P.N. Ostroumov ANL, Argonne, USA
	A multi-MW proton facility, Project X has been proposed and is currently under development at Fermilab. As part of this development program, we are constructing a prototype of the front end of the Project X linac at Fermilab. The construction and successful operations of this facility will validate the concept for the Project X front end, thereby minimizing the primary technical risk element within the Project. The Project X Injector Experiment (PXIE) can be constructed over the period FY12-16 and will include an H⁻ ion source, a CW 2.1-MeV RFQ and two SC cryomodules providing up to 30 MeV energy gain at an average beam current of 1 mA. Successful operations of the facility will demonstrate the viability of novel front end technologies that will find applications beyond Project X in the longer term.

THPPP063	CW Room Temperature Re-buncher for the Project X Front End	3880
	G.V. Romanov, M.H. Awida, M. Chen, I.V. Gonin, S. Kazakov, R.A. Kostin, V.A. Lebedev, N. Solyak, V.P. Yakovlev Fermilab, Batavia, USA
	At Fermilab there is a plan to construct the Project X Injector Experiment (PXIE) facility - a prototype of the front end of the Project X, a multi-MW proton source based on a superconducting linac. The construction and successful operations of this facility will validate the concept for the Project X front end, thereby minimizing the primary technical risk element within the Project. The front end of the linac contains a cw room-temperature MEBT section which comprises an ion source, RFQ, and high-bandwidth bunch selective chopper. The length of the MEBT exceeds 9 m, so three re-bunching cavities are used to support the beam longitudinal dynamics. The paper reports RF design of the re-bunchers along with preliminary beam dynamic and thermal analysis of the cavities.

THPPP090	Project X Functional Requirements Specification	3945
	S.D. Holmes, S. Henderson, R.D. Kephart, J.S. Kerby, I. Kourbanis, V.A. Lebedev, C.S. Mishra, S. Nagaitsev, N. Solyak, R.S. Tschirhart Fermilab, Batavia, USA
	Funding: Work supported by the Fermi Research Alliance, under contract to the U.S. Department of Energy. Project X is a multi-megawatt proton facility being developed to support a world-leading program in Intensity Frontier physics at Fermilab. The facility is designed to support programs in elementary particle and nuclear physics, with possible applications to nuclear energy research. A Functional Requirements Specification has been developed in order to establish performance criteria for the Project X complex in support of these multiple missions, and to assure that the facility is designed with sufficient upgrade capability to provide U.S. leadership for many decades to come. This paper will describe the Functional Requirements for the Project X facility, their recent evolution, and the rationale for these requirements.

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.

THPPR012	Lorentz Force Compensation for Long Pulses in SRF Cavities	3990
	Y.M. Pischalnikov, G.I. Cancelo, B. Chase, D.J. Crawford, D.R. Edstrom, Jr, E.R. Harms, R.A. Kostin, W. Schappert, N. Solyak Fermilab, Batavia, USA
	Lorentz force compensation of 8ms pulses in Tesla style elliptical cavities has been studied in Fermilab SRF Test Facility. Detuning measurements and compensation results are presented.

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

TUPPP092

Renovated Two-stage Bunch Compressor for the International Linear Collider

1801

S. Seletskiy
BNL, Upton, Long Island, New York, USA
N. Solyak
Fermilab, Batavia, USA

The International Linear Collider (ILC) utilizes a Bunch Compressor (BC) in the Damping Ring to Main Linac Transfer Line (RTML) that compresses the RMS bunch length from 6 mm to 300 micrometers before sending the beam to the Main Linac. It was decided to utilize a two stage BC for the design baseline, since it provides an additional option for the ILC to work with 150 micrometers long bunches and reduces the energy spread at the RTML exit under normal operational conditions. In this paper we report the new design of the optimized two-stage bunch compressor.

TUPPR043

New Baseline Design of the ILC RTML System

1915

N. Solyak, V.V. Kapin, A. Vivoli
Fermilab, Batavia, USA
S. Seletskiy
BNL, Upton, Long Island, New York, USA

The new ILC baseline was proposed in 2009 (Strawman baseline - SB2009) to minimize cost of the machine and accommodate many changes made in the design of the accelerator systems. The biggest changes are made in the central area, where BDS, RTML, DR, electron and positron sources are sharing the tunnels. A new layout of the compact DR and re-location of the electron and positron sources to the main tunnel requires a new lattice design for all beamlines in this area. The lattice design was coordinated between accelerator systems and Convention Facility and Siting (CFS) group to eliminate conflicts between beamlines and satisfy construction requirements. In this paper we present a new design of the RTML electron and positron lattices in the central area and other modifications made in the RTML line to accommodate changes to the beamline layouts.

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.

WEPPC045

Optimization of the Geometric Beta for the SSR2 Cavities of the Project X

2312

P. Berrutti, M.H. Awida, I.V. Gonin, N. Solyak, A. Vostrikov, V.P. Yakovlev
Fermilab, Batavia, USA

Project X based on the 3 GeV CW superconducting Linac and is currently in the R&D phase. The cw SC Linac starts from a low-energy SCRF section (2.1 - 165 MeV) containing three different types of resonators. HWR f=162.5 MHz (2.1 - 11 MeV) having β= 0.11, SSR1 f= 325 MHz (11 - 35 MeV) having β = 0.21. In this paper we present the analysis that lead to the final design of SSR2 f=325 MHz cavity (35 - 165 MeV). We present the results of optimization of the geometric beta and the comparison between single, double and triple spoke resonators used in Project X frontend.

WEPPC047

Effects of the RF Field Asymmetry in SC Cavities of the Project X

2318

I.V. Gonin, M.H. Awida, P. Berrutti, A. Saini, B.G. Shteynas, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, USA
P.N. Ostroumov
ANL, Argonne, USA

The low-energy SCRF section of CW SC linac of Project X starts from Half Wave Resonators (HWR) having operating frequency f=162.5 MHz, optimal β= 0.11 and will accelerate the beam from 2 MeV up to 11 MeV. The preliminary analysis of beam dynamics shows that multipole effects caused by asymmetry of RF fields in HWR cavities aren’t negligible. In this paper we present the analysis of influence of multipole effects on beam dynamics and discuss the possible solutions how to compensate these effects.

WEPPC054

Resonance Excitation of Longitudinal High Order Modes in Project X Linac

2336

A.I. Sukhanov, M.H. Awida, I.V. Gonin, T.N. Khabiboulline, A. Lunin, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, USA

Results of simulation of power loss due to excitation of longitudinal high order modes (HOMs) in the accelerating superconducting RF system of CW linac of Project X are presented. Beam structures corresponding to the various modes of Project X operation are considered: CW regime for 3 GeV physics program; pulsed mode for neutrino experiments; and pulsed regime, when Project X linac operates as a driver for Neutrino Factory/Muon Collider. Power loss and associated heat load due to resonance excitation of longitudinal HOMs are shown to be small in all modes of operation. Conclusion is made that HOM couplers can be removed from the design of superconducting RF cavities of Project X linac.

WEPPC059

A Two-stage Injection-locked Magnetron for Accelerators with Superconducting Cavities

2348

G.M. Kazakevich, G. Flanagan, R.P. Johnson, F. Marhauser, M.L. Neubauer
Muons, Inc, Batavia, USA
B. Chase, S. Nagaitsev, R.J. Pasquinelli, N. Solyak, V. Tupikov, D. Wolff, V.P. Yakovlev
Fermilab, Batavia, USA

Funding: Supported in part by SBIR Grant 4743 11SC06261
A concept for a two-stage injection-locked CW magnetron intended to drive Superconducting Cavities (SC) for intensity-frontier accelerators has been proposed. The concept is based on a theoretical model that considers a magnetron as a forced oscillator; the model has been experimentally verified with a 2.5 MW pulsed magnetron. The two-stage CW magnetron can be used as a RF power source for Fermilab’s Project-X to feed separately each of the SC of the 8 GeV pulsed linac. For Project-X the 1.3 GHz two-stage magnetron with output power of 20-25 kW and expected output/input power ratio of about 35-40 dB would operate in a quasi-CW mode with a pulse duration ≤ 10 ms and repetition rate of 10 Hz. The magnetrons for both stages should be based on the commercial prototypes to decrease the cost of the system. An experimental model of the two-stage CW S-band magnetron with peak power of 1 kW, with pulse duration of 1-10 ms, has been developed and built for study. A description of the theoretical and experimental models, simulations, and experimental results are presented and discussed in this work.

WEPPD035

Design Considerations for an MEBT Chopper Absorber of 2.1MeV H⁻ at the Project X Injector Experiment at Fermilab

2585

C.M. Baffes, M.H. Awida, A.Z. Chen, Y.I. Eidelman, V.A. Lebedev, L.R. Prost, A.V. Shemyakin, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, USA

Funding: Operated by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the United States Department of Energy
The Project X Injector Experiment (PXIE) will be a prototype of the Project X front end that will be used to validate the design concept and decrease technical risks. One of the most challenging components of PXIE is the wide-band chopping system of the Medium Energy Beam Transport (MEBT) section, which will form an arbitrary bunch pattern from the initially CW 162.5 MHz 5mA beam. The present scenario assumes diverting 80% of the beam to an absorber to provide a beam with the average current of 1mA to SRF linac. This absorber must withstand a high level of energy deposition and high ion fluence, while being positioned in proximity of the superconductive cavities. This paper discusses design considerations for the absorber, including specific challenges as spreading of energy deposition, management of temperatures and temperature-induced mechanical stresses, radiation effects, surface effects (sputtering and blistering), and maintaining vacuum quality. Thermal and mechanical analyses of a conceptual design are presented, and future plans for the fabrication and testing of a prototype are described.

WEPPD058

The Project-X 3 GeV Beam Distribution System

2651

D.E. Johnson, M.H. Awida, M.S. Champion, I.V. Gonin, A.L. Klebaner, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, USA

In the Project X facility, a 3 GeV H⁻ CW beam is delivered to three users simultaneously. This will be accomplished by selectively filling appropriate RF buckets at the front end of the linac and then utilizing a RF splitter to transversely separate bunches to three different target halls. A compact TE113 squashed-wall superconducting RF cavity has been proposed to produce the initial vertical deflection. The transport line optics, cavity design parameters, and cryogenic system requirements will be presented.

WEPPR029

Alternative Cavity for H E Part of the Project X linac

2997

A. Lunin, A. Saini, N. Solyak, A.I. Sukhanov, V.P. Yakovlev
Fermilab, Batavia, USA

An alternative superconducting elliptical cavity is suggested for High Energy (HE) part of the Project X linac. The cavity is suitable to operate at CW regime with high beam current (10 mA), which is critical for Accelerator-Driven Subcritical (ADS) systems and for intense muon source for future Neutrino Factory or Muon Collider. We present the algorithm of the cavity shape optimization, comprehensive tolerances analysis and the solution for monopole High Order Modes (HOM) damping. Based on these results we estimated the probabilities of cryogenic losses per cryomodule and a growth of the beam longitudinal emittance due to the resonance excitation of monopole HOMs in the HE linac for Project X.

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.

THPPP058

PXIE: Project X Injector Experiment

3874

S. Nagaitsev, S.D. Holmes, R.D. Kephart, J.S. Kerby, V.A. Lebedev, C.S. Mishra, A.V. Shemyakin, N. Solyak, R.P. Stanek
Fermilab, Batavia, USA
D. Li
LBNL, Berkeley, California, USA
P.N. Ostroumov
ANL, Argonne, USA

A multi-MW proton facility, Project X has been proposed and is currently under development at Fermilab. As part of this development program, we are constructing a prototype of the front end of the Project X linac at Fermilab. The construction and successful operations of this facility will validate the concept for the Project X front end, thereby minimizing the primary technical risk element within the Project. The Project X Injector Experiment (PXIE) can be constructed over the period FY12-16 and will include an H⁻ ion source, a CW 2.1-MeV RFQ and two SC cryomodules providing up to 30 MeV energy gain at an average beam current of 1 mA. Successful operations of the facility will demonstrate the viability of novel front end technologies that will find applications beyond Project X in the longer term.

THPPP063

CW Room Temperature Re-buncher for the Project X Front End

3880

G.V. Romanov, M.H. Awida, M. Chen, I.V. Gonin, S. Kazakov, R.A. Kostin, V.A. Lebedev, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, USA

At Fermilab there is a plan to construct the Project X Injector Experiment (PXIE) facility - a prototype of the front end of the Project X, a multi-MW proton source based on a superconducting linac. The construction and successful operations of this facility will validate the concept for the Project X front end, thereby minimizing the primary technical risk element within the Project. The front end of the linac contains a cw room-temperature MEBT section which comprises an ion source, RFQ, and high-bandwidth bunch selective chopper. The length of the MEBT exceeds 9 m, so three re-bunching cavities are used to support the beam longitudinal dynamics. The paper reports RF design of the re-bunchers along with preliminary beam dynamic and thermal analysis of the cavities.

THPPP090

Project X Functional Requirements Specification

3945

S.D. Holmes, S. Henderson, R.D. Kephart, J.S. Kerby, I. Kourbanis, V.A. Lebedev, C.S. Mishra, S. Nagaitsev, N. Solyak, R.S. Tschirhart
Fermilab, Batavia, USA

Funding: Work supported by the Fermi Research Alliance, under contract to the U.S. Department of Energy.
Project X is a multi-megawatt proton facility being developed to support a world-leading program in Intensity Frontier physics at Fermilab. The facility is designed to support programs in elementary particle and nuclear physics, with possible applications to nuclear energy research. A Functional Requirements Specification has been developed in order to establish performance criteria for the Project X complex in support of these multiple missions, and to assure that the facility is designed with sufficient upgrade capability to provide U.S. leadership for many decades to come. This paper will describe the Functional Requirements for the Project X facility, their recent evolution, and the rationale for these requirements.

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.

THPPR012

Lorentz Force Compensation for Long Pulses in SRF Cavities

3990

Y.M. Pischalnikov, G.I. Cancelo, B. Chase, D.J. Crawford, D.R. Edstrom, Jr, E.R. Harms, R.A. Kostin, W. Schappert, N. Solyak
Fermilab, Batavia, USA

Lorentz force compensation of 8ms pulses in Tesla style elliptical cavities has been studied in Fermilab SRF Test Facility. Detuning measurements and compensation results are presented.