PAC2013 - List of Authors (Awida, M.H.)

Paper	Title	Page
WEPAC21	Tuning Process of SSR1 Cavity for Project X at FNAL	832
	P. Berrutti, M.H. Awida, T.N. Khabiboulline, D. Passarelli, L. Ristori, V.P. Yakovlev Fermilab, Batavia, USA
	SSR1 is a family of single spoke resonators to be used in Project X at Fermi National Laboratory. These cavities operate in CW regime having nominal frequency of 325 MHz and optimal beta of 0.22. SSR1 cavities will accelerate H⁻ ions after the Half Wave Resonator (HWR) section from 9 MeV to 32 MeV. In the near future this cavity will be used in Project X Injector Experiment (PXIE), which contains the ion source, the LEBT, the MEBT, the RFQ of Project X, and a cryogenic temperature section, having one HWR and one SSR1 cryomodule. SSR1 cavities have been built and tested at FNAL, the preparation of these resonators includes RF tuning which is the main focus of this paper. The frequency of the cavity is carefully chosen prior to the vertical test, and it is adjusted before welding the helium vessel to obtain 325 MHz nominal frequency for the dressed cavity in operating conditions. Several SSR1 cavities have been tuned at FNAL, the procedure, the hardware and the data are presented.

WEPAC25	New Helium Vessel and Lever Tuner Designs for the 650 MHz Cavities for Project X	841
	I.V. Gonin, M.H. Awida, E. Borissov, M.H. Foley, C.J. Grimm, T.N. Khabiboulline, M. Merio, Y.M. Pischalnikov, L. Ristori, V.P. Yakovlev Fermilab, Batavia, USA
	The design of 5-cell elliptical 650 MHz β=0.9 cavities to accelerate H⁻ beam of 1 mA average current in the range 467-3000 MeV for the Project X Linac is currently under development at Fermilab. A new design of the Helium Vessel (HV) was developed for these cavities with the main goal of optimizing the frequency sensitivity df/dP by keeping the cavity stiffness reasonably small. We also present a design of the new lever tuner system. The HV in the new design is equipped with the tuner located at the end of the cavity instead of the initially proposed blade tuner located in the middle. We will present mechanical design results and ANSYS analyses for both the slow and fast tuners.

WEPAC29	CM2, Second 1.3GHz Cryomodule Fabrication at Fermilab	844
	T.T. Arkan, M.H. Awida, P. Berrutti, E. Borissov, C.M. Ginsburg, C.J. Grimm, E.R. Harms, A. Hocker, T.N. Khabiboulline, Y.O. Orlov, T.J. Peterson, R.V. Pilipenko, Y.M. Pischalnikov, K.S. Premo, L. Ristori, W. Schappert, V.P. Yakovlev Fermilab, Batavia, USA
	Funding: US Department of Energy CM2 is the second 1.3GHz Cryomodule assembled at the Cryomodule Assembly Facility (CAF) in Fermi National Accelerator Laboratory. The string has a doublet magnet, beam position monitor and eight cavities. All the cavities are qualified at 35 MV / m gradient at the Horizontal Test Facility before assembly. The dressed cavities were outfitted with magnetic shielding, blade tuner, and the cold mass was assembled based on the Tesla TTF Type III+ cryomodule design. CM2 is currently being installed into the test stand in NML where it will be cooled down and high power tested. CM2 will also be the first cryomodule that an electron beam will be put through at the NML facility. This will be a proof of principle for the planned Advanced Superconducting Test Accelerator (ASTA) facility at NML. This paper describes the assembly steps, the quality assurance methods and the challenges that we experienced during assembly and qualification steps at CAF. De

WEPAC32	Wakefield Loss Analysis of the Elliptical 3.9 GHz Third Harmonic Cavity	847
	M.H. Awida, P. Berrutti, T.N. Khabiboulline, A. Saini, V.P. Yakovlev Fermilab, Batavia, USA
	Third harmonic 3.9 GHz elliptical cavities are planned to be used in many particle accelerator projects such as XFEL, NGLS, and ASTA. In this paper, the wakefield losses due to single bunch passage are analysed considering bunches of RMS length 8 mm down to ultra short ones of 10 μm length. Both the loss and kick factors are numerically calculated for bunches of relatively long length (>1 mm) using CST wakefield solver. The data is then used to extrapolate asymptotically the values for ultra-short bunches by finding the wake functions. These calculations are essential to estimate the cryogenic losses in cryomodules and for beam dynamic analysis.

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

Tuning Process of SSR1 Cavity for Project X at FNAL

832

P. Berrutti, M.H. Awida, T.N. Khabiboulline, D. Passarelli, L. Ristori, V.P. Yakovlev
Fermilab, Batavia, USA

SSR1 is a family of single spoke resonators to be used in Project X at Fermi National Laboratory. These cavities operate in CW regime having nominal frequency of 325 MHz and optimal beta of 0.22. SSR1 cavities will accelerate H⁻ ions after the Half Wave Resonator (HWR) section from 9 MeV to 32 MeV. In the near future this cavity will be used in Project X Injector Experiment (PXIE), which contains the ion source, the LEBT, the MEBT, the RFQ of Project X, and a cryogenic temperature section, having one HWR and one SSR1 cryomodule. SSR1 cavities have been built and tested at FNAL, the preparation of these resonators includes RF tuning which is the main focus of this paper. The frequency of the cavity is carefully chosen prior to the vertical test, and it is adjusted before welding the helium vessel to obtain 325 MHz nominal frequency for the dressed cavity in operating conditions. Several SSR1 cavities have been tuned at FNAL, the procedure, the hardware and the data are presented.

WEPAC25

New Helium Vessel and Lever Tuner Designs for the 650 MHz Cavities for Project X

841

I.V. Gonin, M.H. Awida, E. Borissov, M.H. Foley, C.J. Grimm, T.N. Khabiboulline, M. Merio, Y.M. Pischalnikov, L. Ristori, V.P. Yakovlev
Fermilab, Batavia, USA

The design of 5-cell elliptical 650 MHz β=0.9 cavities to accelerate H⁻ beam of 1 mA average current in the range 467-3000 MeV for the Project X Linac is currently under development at Fermilab. A new design of the Helium Vessel (HV) was developed for these cavities with the main goal of optimizing the frequency sensitivity df/dP by keeping the cavity stiffness reasonably small. We also present a design of the new lever tuner system. The HV in the new design is equipped with the tuner located at the end of the cavity instead of the initially proposed blade tuner located in the middle. We will present mechanical design results and ANSYS analyses for both the slow and fast tuners.

WEPAC29

CM2, Second 1.3GHz Cryomodule Fabrication at Fermilab

844

T.T. Arkan, M.H. Awida, P. Berrutti, E. Borissov, C.M. Ginsburg, C.J. Grimm, E.R. Harms, A. Hocker, T.N. Khabiboulline, Y.O. Orlov, T.J. Peterson, R.V. Pilipenko, Y.M. Pischalnikov, K.S. Premo, L. Ristori, W. Schappert, V.P. Yakovlev
Fermilab, Batavia, USA

Funding: US Department of Energy
CM2 is the second 1.3GHz Cryomodule assembled at the Cryomodule Assembly Facility (CAF) in Fermi National Accelerator Laboratory. The string has a doublet magnet, beam position monitor and eight cavities. All the cavities are qualified at 35 MV / m gradient at the Horizontal Test Facility before assembly. The dressed cavities were outfitted with magnetic shielding, blade tuner, and the cold mass was assembled based on the Tesla TTF Type III+ cryomodule design. CM2 is currently being installed into the test stand in NML where it will be cooled down and high power tested. CM2 will also be the first cryomodule that an electron beam will be put through at the NML facility. This will be a proof of principle for the planned Advanced Superconducting Test Accelerator (ASTA) facility at NML. This paper describes the assembly steps, the quality assurance methods and the challenges that we experienced during assembly and qualification steps at CAF. De

WEPAC32

Wakefield Loss Analysis of the Elliptical 3.9 GHz Third Harmonic Cavity

847

M.H. Awida, P. Berrutti, T.N. Khabiboulline, A. Saini, V.P. Yakovlev
Fermilab, Batavia, USA

Third harmonic 3.9 GHz elliptical cavities are planned to be used in many particle accelerator projects such as XFEL, NGLS, and ASTA. In this paper, the wakefield losses due to single bunch passage are analysed considering bunches of RMS length 8 mm down to ultra short ones of 10 μm length. Both the loss and kick factors are numerically calculated for bunches of relatively long length (>1 mm) using CST wakefield solver. The data is then used to extrapolate asymptotically the values for ultra-short bunches by finding the wake functions. These calculations are essential to estimate the cryogenic losses in cryomodules and for beam dynamic analysis.

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.