IPAC2011 - List of Authors (Faus-Golfe, A.)

Paper	Title	Page
TUPC011	Striplines for CLIC Pre-Damping and Damping Rings*	1012
	C. Belver-Aguilar, A. Faus-Golfe IFIC, Valencia, Spain M.J. Barnes, G. Rumolo CERN, Geneva, Switzerland F. Toral CIEMAT, Madrid, Spain C. Zannini EPFL, Lausanne, Switzerland
	The Compact Linear Collider (CLIC) study explores the scheme for an electron-positron collider with high luminosity and a nominal center-of-mass energy of 3 TeV: CLIC would complement LHC physics in the multi-TeV range. The CLIC design relies on the presence of Pre-Damping Rings (PDR) and Damping Rings (DR) to achieve, through synchrotron radiation, the very low emittance needed to fulfil the luminosity requirements. The specifications for the kicker systems are very challenging and include very low beam coupling impedance and excellent field homogeneity: striplines have been chosen for the kicker elements. Analytical calculations have been carried out to determine the effect of tapering upon the high frequency beam coupling impedance. In addition detailed numerical modeling of the field homogeneity has been performed and the sensitivity of the homogeneity to various parameters, including stripline cross-section, has been studied. This paper presents the main conclusions of the beam impedance calculations and field homogeneity predictions.

TUPC127	Optical Transition Radiation System for ATF2	1317
	J. Alabau-Gonzalvo, C. Blanch Gutierrez, A. Faus-Golfe, J.J. García-Garrigós IFIC, Valencia, Spain J. Cruz, D.J. McCormick, G.R. White, M. Woodley SLAC, Menlo Park, California, USA
	Funding: Funding Agency: FPA2010-21456-C02-01 Work supported in part by Department of Energy Contract DE-AC02-76SF00515 In this paper we present the first measurements performed during the fall 2010 and early 2011 runs. Software development, simulations and hardware improvements to the Multi-Optical Transition Radiation System installed in the beam diagnostic section of the Extraction (EXT) line of ATF2 are described. 2D emittance measurements have been performed and the system is being routinely used for coupling correction. Realistic beam simulations have been made and compared with the measurements. A 4D emittance procedure, yet to be implemented, is also discussed. A demagnifier lens system to improve the beam finding procedure has been designed and will be implemented in a future run. Finally, we discuss further verification work planned for the next run period of ATF.

TUPC129	A Beam Position System for Hadrontherapy Facilities	1323
	A. Faus-Golfe, C. Belver-Aguilar, C. Blanch Gutierrez, J.J. García-Garrigós IFIC, Valencia, Spain E. Benveniste, M. Haguenauer, P. Poilleux LLR, Palaiseau, France
	Funding: MICINN-FPA:AIC10-D-000518 Essential parts of the needed instrumentation for the beam control in the Hadrontherapy accelerators are the Beam Position Monitors (BPM). The measurement of the beam position in Hadronterapy accelerators become more important at the secondary transport lines towards the patient room where this parameter must be completely determined. The BPM described in this paper is a new type of BPM based on four scintillating fibers coupled to four photodiodes to detect the light produced by the fibers when intercepting the beam. We present here the study of the different photodiodes able to read the light emitted by the scintillating fiber, the tests performed in order to find the most suitable photodiode to measure the beam position from the variations in the beam current, the mechanical design and the corresponding acquisition electronics.

TUPC130	Beam Test Performance of the Beam Position Monitors for the TBL Line of the CTF3 at CERN	1326
	J.J. García-Garrigós, C. Blanch Gutierrez, J.V. Civera, A. Faus-Golfe IFIC, Valencia, Spain S. Döbert CERN, Geneva, Switzerland
	Funding: Funding Agency: FPA2010-21456-C02-01 A series of Inductive Pick-Ups (IPU) for Beam Position Monitoring (BPM) with its associated electronics were designed, constructed and tested at IFIC. A full set of 16 BPMs, so called BPS units, were successfully installed in the Test Beam Line (TBL) of the CLIC Test Facility (CTF3) at CERN. In this paper we present the results of the beam test carried out on the BPS units of the TBL in order to determine their beam performances and check the specified operational requirements. We focus particularly on the position resolution parameter which is the BPS figure of merit according to TBL demands and is expected to reach the 5um resolution at maximum beam current (28A). The beam test results of the BPS units are also compared with the parameters from their previous characterization test at lab.

WEPS045	Feasibility Study of a High-gradient Linac for Hadrontherapy	2589
	S. Verdú-Andrés, U. Amaldi, A. Degiovanni TERA, Novara, Italy A. Faus-Golfe, S. Verdú-Andrés IFIC, Valencia, Spain P.A. Posocco CERN, Geneva, Switzerland
	Funding: The research leading to this results has been funded by the Seventh Framework Program [FP7/2007-2013] under grant agreement number 215840-2. Compact, reliable and little consuming accelerators are needed for tumor treatment with hadrons. As solution, TERA proposes CABOTO (CArbon BOoster for Therapy in Oncology), a linac which boosts the energy of carbon ions and H₂ molecules coming from a cyclotron. The linac, typically a Side-Coupled Linac (SCL), is divided into several modules. The beam energy can be varied in steps of about 15 MeV/u without using absorbers by acting on the power (amplitude and/or phase) that feeds the different modules of the linac. This work presents the structure design of a 5.7 GHz high repetition rate SCL for a cyclinac, that accelerates carbon ions from 150 up to 400 MeV/u in less than 25 meters. The beam dynamics for this linac and its particular energy selection system is also discussed for different beam energy outputs.

THPZ032	Evaluation of the Combined Betatron and Momentum Cleaning in Point 3 in Terms of Cleaning Efficiency and Energy Deposition for the LHC Collimation Upgrade	3762
	L. Lari, R.W. Assmann, V. Boccone, M. Brugger, F. Cerutti, A. Ferrari, A. Rossi, R. Versaci, V. Vlachoudis, D. Wollmann CERN, Geneva, Switzerland A. Faus-Golfe, L. Lari IFIC, Valencia, Spain A. Mereghetti UMAN, Manchester, United Kingdom
	Funding: This work has been carried out through of the European Coordination for Accelerator Research and Development (EuCARD), co-sponsored by EU 7th Framework Program. The Phase I LHC Collimation System Upgrade could include moving part of the Betatron Cleaning from LHC Point 7 to Point 3 to improve both operation flexibility and intensity reach. In addition, the partial relocation of beam losses from the current Betatron cleaning region at Point 7 will mitigate the risks of Single Event Upsets to equipment installed in adjacent and partly not adequate shielded areas. A combined Betatron and Momentum Cleaning scenario at Point 3 implies the installation of new collimators and a new collimator aperture layout. This paper shows the whole LHC Collimator Efficiency variation with the new layout proposed at different beam energies. As part of the evaluation, energy deposition distribution in the IR3 region gives indications about the effect of this new implementation not only on the collimators themselves but also on the other beam line elements.

Paper

Title

Page

Striplines for CLIC Pre-Damping and Damping Rings*

1012

C. Belver-Aguilar, A. Faus-Golfe
IFIC, Valencia, Spain
M.J. Barnes, G. Rumolo
CERN, Geneva, Switzerland
F. Toral
CIEMAT, Madrid, Spain
C. Zannini
EPFL, Lausanne, Switzerland

The Compact Linear Collider (CLIC) study explores the scheme for an electron-positron collider with high luminosity and a nominal center-of-mass energy of 3 TeV: CLIC would complement LHC physics in the multi-TeV range. The CLIC design relies on the presence of Pre-Damping Rings (PDR) and Damping Rings (DR) to achieve, through synchrotron radiation, the very low emittance needed to fulfil the luminosity requirements. The specifications for the kicker systems are very challenging and include very low beam coupling impedance and excellent field homogeneity: striplines have been chosen for the kicker elements. Analytical calculations have been carried out to determine the effect of tapering upon the high frequency beam coupling impedance. In addition detailed numerical modeling of the field homogeneity has been performed and the sensitivity of the homogeneity to various parameters, including stripline cross-section, has been studied. This paper presents the main conclusions of the beam impedance calculations and field homogeneity predictions.

TUPC127

Optical Transition Radiation System for ATF2

1317

J. Alabau-Gonzalvo, C. Blanch Gutierrez, A. Faus-Golfe, J.J. García-Garrigós
IFIC, Valencia, Spain
J. Cruz, D.J. McCormick, G.R. White, M. Woodley
SLAC, Menlo Park, California, USA

Funding: Funding Agency: FPA2010-21456-C02-01 Work supported in part by Department of Energy Contract DE-AC02-76SF00515
In this paper we present the first measurements performed during the fall 2010 and early 2011 runs. Software development, simulations and hardware improvements to the Multi-Optical Transition Radiation System installed in the beam diagnostic section of the Extraction (EXT) line of ATF2 are described. 2D emittance measurements have been performed and the system is being routinely used for coupling correction. Realistic beam simulations have been made and compared with the measurements. A 4D emittance procedure, yet to be implemented, is also discussed. A demagnifier lens system to improve the beam finding procedure has been designed and will be implemented in a future run. Finally, we discuss further verification work planned for the next run period of ATF.

TUPC129

A Beam Position System for Hadrontherapy Facilities

1323

A. Faus-Golfe, C. Belver-Aguilar, C. Blanch Gutierrez, J.J. García-Garrigós
IFIC, Valencia, Spain
E. Benveniste, M. Haguenauer, P. Poilleux
LLR, Palaiseau, France

Funding: MICINN-FPA:AIC10-D-000518
Essential parts of the needed instrumentation for the beam control in the Hadrontherapy accelerators are the Beam Position Monitors (BPM). The measurement of the beam position in Hadronterapy accelerators become more important at the secondary transport lines towards the patient room where this parameter must be completely determined. The BPM described in this paper is a new type of BPM based on four scintillating fibers coupled to four photodiodes to detect the light produced by the fibers when intercepting the beam. We present here the study of the different photodiodes able to read the light emitted by the scintillating fiber, the tests performed in order to find the most suitable photodiode to measure the beam position from the variations in the beam current, the mechanical design and the corresponding acquisition electronics.

TUPC130

Beam Test Performance of the Beam Position Monitors for the TBL Line of the CTF3 at CERN

1326

J.J. García-Garrigós, C. Blanch Gutierrez, J.V. Civera, A. Faus-Golfe
IFIC, Valencia, Spain
S. Döbert
CERN, Geneva, Switzerland

Funding: Funding Agency: FPA2010-21456-C02-01
A series of Inductive Pick-Ups (IPU) for Beam Position Monitoring (BPM) with its associated electronics were designed, constructed and tested at IFIC. A full set of 16 BPMs, so called BPS units, were successfully installed in the Test Beam Line (TBL) of the CLIC Test Facility (CTF3) at CERN. In this paper we present the results of the beam test carried out on the BPS units of the TBL in order to determine their beam performances and check the specified operational requirements. We focus particularly on the position resolution parameter which is the BPS figure of merit according to TBL demands and is expected to reach the 5um resolution at maximum beam current (28A). The beam test results of the BPS units are also compared with the parameters from their previous characterization test at lab.

WEPS045

Feasibility Study of a High-gradient Linac for Hadrontherapy

2589

S. Verdú-Andrés, U. Amaldi, A. Degiovanni
TERA, Novara, Italy
A. Faus-Golfe, S. Verdú-Andrés
IFIC, Valencia, Spain
P.A. Posocco
CERN, Geneva, Switzerland

Funding: The research leading to this results has been funded by the Seventh Framework Program [FP7/2007-2013] under grant agreement number 215840-2.
Compact, reliable and little consuming accelerators are needed for tumor treatment with hadrons. As solution, TERA proposes CABOTO (CArbon BOoster for Therapy in Oncology), a linac which boosts the energy of carbon ions and H₂ molecules coming from a cyclotron. The linac, typically a Side-Coupled Linac (SCL), is divided into several modules. The beam energy can be varied in steps of about 15 MeV/u without using absorbers by acting on the power (amplitude and/or phase) that feeds the different modules of the linac. This work presents the structure design of a 5.7 GHz high repetition rate SCL for a cyclinac, that accelerates carbon ions from 150 up to 400 MeV/u in less than 25 meters. The beam dynamics for this linac and its particular energy selection system is also discussed for different beam energy outputs.

THPZ032

Evaluation of the Combined Betatron and Momentum Cleaning in Point 3 in Terms of Cleaning Efficiency and Energy Deposition for the LHC Collimation Upgrade

3762

L. Lari, R.W. Assmann, V. Boccone, M. Brugger, F. Cerutti, A. Ferrari, A. Rossi, R. Versaci, V. Vlachoudis, D. Wollmann
CERN, Geneva, Switzerland
A. Faus-Golfe, L. Lari
IFIC, Valencia, Spain
A. Mereghetti
UMAN, Manchester, United Kingdom

Funding: This work has been carried out through of the European Coordination for Accelerator Research and Development (EuCARD), co-sponsored by EU 7th Framework Program.
The Phase I LHC Collimation System Upgrade could include moving part of the Betatron Cleaning from LHC Point 7 to Point 3 to improve both operation flexibility and intensity reach. In addition, the partial relocation of beam losses from the current Betatron cleaning region at Point 7 will mitigate the risks of Single Event Upsets to equipment installed in adjacent and partly not adequate shielded areas. A combined Betatron and Momentum Cleaning scenario at Point 3 implies the installation of new collimators and a new collimator aperture layout. This paper shows the whole LHC Collimator Efficiency variation with the new layout proposed at different beam energies. As part of the evaluation, energy deposition distribution in the IR3 region gives indications about the effect of this new implementation not only on the collimators themselves but also on the other beam line elements.