PAC2013 - List of Authors (Chase, B.)

Paper

Title

Page

Longitudinal Beam Dynamics and LLRF Requirements for the Project X Pulsed Linac

439

A. Vivoli, G.I. Cancelo, B. Chase, N. Solyak, P. Varghese
Fermilab, Batavia, USA

Project X is a high intensity proton facility being developed to support the intensity frontier physics program over the next two decades at Fermilab. The Reference Design is based on a continuous wave (CW) superconducting 3 GeV linac providing up to 1 and 3 MW of beam power at 1 and 3 GeV respectively, while a superconducting pulsed linac provides acceleration of roughly 4.3% of the beam delivered from the CW linac to the 8 GeV injection energy of the existing Recycler/Main Injector complex. In this paper we present the results of simulation of longitudinal beam dynamics and Low Level RF (LLRF) control system in the pulsed linac, operated for long pulses in presence of errors and cavity detuning for different RF configurations and settings, and set the requirements for the LLRF necessary to fulfill the specifications of the design.

Slides TUODB2 [8.618 MB]

WEPHO15

Modeling of Magnetron Transmitter for the Project X CW 1 GEV Linac

966

G.M. Kazakevich, R.P. Johnson
Muons, Inc, Illinois, USA
B. Chase, R.J. Pasquinelli, V.P. Yakovlev
Fermilab, Batavia, USA

A 650 MHz 50 kW transmitter with a wide-band control in phase and power, based on injection-locked CW magnetrons, intended to drive individually Superconducting RF (SRF) cavities has been proposed for the Project X CW 1 GeV linac. Utilization of the magnetron RF sources for the intensity-frontier project will save a significant capital cost in comparison with traditional RF sources based on klystrons, Inductive Output Tubes (IOTs), solid-state amplifiers. The transmitter setup has been modelled experimentally and by simulation using 2.45 GHz CW magnetrons with output power up to 1 kW. The measurements and simulations performed with the injection-locked magnetrons demonstrated capability of the proposed transmitter concept to power individually the superconducting cavities suppressing parasitic modulation of the accelerating field caused by mechanical oscillation (microphonics and oscillations resulted from Lorentz-force), beam loading, dynamic tuning errors, and other low-frequency disturbances of the magnetron performance. Results of the experimental and theoretical modelling are analysed and discussed in this paper.

THPBA17

Status Of PXIE 200 Ω MEBT Kicker Development

1268

G.W. Saewert, M.H. Awida, B. Chase, H. Pfeffer, D. Wolff
Fermilab, Batavia, USA
D. Frolov
Kuban State University, Krasnodar, Russia

Funding: Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U. S. Department of Energy
The proposed Project X machine at Fermilab must deliver a widely varying bunch pattern to provide beam to several experiments quasi-simultaneously. Beam will be chopped on a bunch-by-bunch basis. The Project X Injector Experiment (PXIE) will be the test bed to demonstrate the beam chopping ability to form an arbitrary bunch pattern. The chopper system will selectively kick out individual beam bunches in the 2.1 MeV Medium Energy Beam Transport (MEBT) section downstream of the RFQ producing a CW 162.5 MHz H⁻ bunch stream. The chopper system will consist of two individual traveling wave kickers working in sync to deflect undesired beam bunches to an absorber. Presently two kicker system versions are under development. One proposed version is a 50 Ω planar structure driven by a ±250 V linear amplifier. The second proposed version is a 200 Ω helical, microstrip line structure driven by a 500 V bipolar switch. This paper describes the development status of the 200 Ω version and includes the design concept, comparison of 3D modeling work with prototype measurements, 200 Ω hardware description and progress with the driver.

Paper	Title	Page
TUODB2	Longitudinal Beam Dynamics and LLRF Requirements for the Project X Pulsed Linac	439
	A. Vivoli, G.I. Cancelo, B. Chase, N. Solyak, P. Varghese Fermilab, Batavia, USA
	Project X is a high intensity proton facility being developed to support the intensity frontier physics program over the next two decades at Fermilab. The Reference Design is based on a continuous wave (CW) superconducting 3 GeV linac providing up to 1 and 3 MW of beam power at 1 and 3 GeV respectively, while a superconducting pulsed linac provides acceleration of roughly 4.3% of the beam delivered from the CW linac to the 8 GeV injection energy of the existing Recycler/Main Injector complex. In this paper we present the results of simulation of longitudinal beam dynamics and Low Level RF (LLRF) control system in the pulsed linac, operated for long pulses in presence of errors and cavity detuning for different RF configurations and settings, and set the requirements for the LLRF necessary to fulfill the specifications of the design.
	Slides TUODB2 [8.618 MB]

WEPHO15	Modeling of Magnetron Transmitter for the Project X CW 1 GEV Linac	966
	G.M. Kazakevich, R.P. Johnson Muons, Inc, Illinois, USA B. Chase, R.J. Pasquinelli, V.P. Yakovlev Fermilab, Batavia, USA
	A 650 MHz 50 kW transmitter with a wide-band control in phase and power, based on injection-locked CW magnetrons, intended to drive individually Superconducting RF (SRF) cavities has been proposed for the Project X CW 1 GeV linac. Utilization of the magnetron RF sources for the intensity-frontier project will save a significant capital cost in comparison with traditional RF sources based on klystrons, Inductive Output Tubes (IOTs), solid-state amplifiers. The transmitter setup has been modelled experimentally and by simulation using 2.45 GHz CW magnetrons with output power up to 1 kW. The measurements and simulations performed with the injection-locked magnetrons demonstrated capability of the proposed transmitter concept to power individually the superconducting cavities suppressing parasitic modulation of the accelerating field caused by mechanical oscillation (microphonics and oscillations resulted from Lorentz-force), beam loading, dynamic tuning errors, and other low-frequency disturbances of the magnetron performance. Results of the experimental and theoretical modelling are analysed and discussed in this paper.

THPBA17	Status Of PXIE 200 Ω MEBT Kicker Development	1268
	G.W. Saewert, M.H. Awida, B. Chase, H. Pfeffer, D. Wolff Fermilab, Batavia, USA D. Frolov Kuban State University, Krasnodar, Russia
	Funding: Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U. S. Department of Energy The proposed Project X machine at Fermilab must deliver a widely varying bunch pattern to provide beam to several experiments quasi-simultaneously. Beam will be chopped on a bunch-by-bunch basis. The Project X Injector Experiment (PXIE) will be the test bed to demonstrate the beam chopping ability to form an arbitrary bunch pattern. The chopper system will selectively kick out individual beam bunches in the 2.1 MeV Medium Energy Beam Transport (MEBT) section downstream of the RFQ producing a CW 162.5 MHz H⁻ bunch stream. The chopper system will consist of two individual traveling wave kickers working in sync to deflect undesired beam bunches to an absorber. Presently two kicker system versions are under development. One proposed version is a 50 Ω planar structure driven by a ±250 V linear amplifier. The second proposed version is a 200 Ω helical, microstrip line structure driven by a 500 V bipolar switch. This paper describes the development status of the 200 Ω version and includes the design concept, comparison of 3D modeling work with prototype measurements, 200 Ω hardware description and progress with the driver.