IPAC2012 - List of Keywords (linear-collider)

Paper	Title	Other Keywords	Page
MOEPPB001	RF-breakdown Kicks at the CTF3 Two-beam Test Stand	linac, extraction, collider, acceleration	73
	A. Palaia, M. Jacewicz, T. Muranaka, R.J.M.Y. Ruber, V.G. Ziemann Uppsala University, Uppsala, Sweden W. Farabolini CEA/DSM/IRFU, France
	The measurement of the effects of RF-breakdown on the beam in CLIC prototype accelerator structures is one of the key aspects of the CLIC two-beam acceleration scheme being addressed at the Two-beam Test Stand (TBTS) at CTF3. RF-breakdown can randomly cause energy loss and transverse kicks to the beam. Transverse kicks have been measured by means of a screen intercepting the beam after the accelerator structure. In correspondence of a RF-breakdown we detect a double beam spot which we interpret as a sudden change of the beam trajectory within a single beam pulse. To time-resolve such effect, the TBTS has been equipped with five inductive Beam Position Monitors (BPMs) and a spectrometer line to measure both relative changes of the beam trajectory and energy losses. Here we discuss the methodology used and we present the latest results of such measurements.

MOPPR065	A Low-latency Sub-micron Resolution Stripline Beam Position Monitoring System for Single-pass Beamlines	monitoring, feedback, extraction, collider	933
	P. Burrows, D.R. Bett, N. Blaskovic Kraljevic, G.B. Christian, M.R. Davis, A. Gerbershagen, C. Perry JAI, Oxford, United Kingdom R. Apsimon, B. Constance CERN, Geneva, Switzerland J. Resta-López IFIC, Valencia, Spain
	A low-latency, sub-micron resolution stripline beam position monitoring system has been developed for use in single-pass beamlines. The fast analogue front-end signal processor is based on a single-stage RF down-mixer and is combined with an FPGA-based system for digitisation and further signal processing. The system has been deployed and tested with beam at the Accelerator Test Facility at KEK. Performance results are presented on the calibration, resolution and stability of the system. A detailed simulation has been developed that is able to account for the measured performance.

MOPPR066	Study of Transverse Pulse-to-Pulse Orbit Jitter at the KEK Accelerator Test Facility 2 (ATF2)	simulation, extraction, feedback, controls	936
	J. Resta-López, J. Alabau-Gonzalvo IFIC, Valencia, Spain R. Apsimon, B. Constance, A. Gerbershagen CERN, Geneva, Switzerland D.R. Bett, P. Burrows, G.B. Christian, M.R. Davis, C. Perry JAI, Oxford, United Kingdom
	Funding: FPA2010-21456-C02-01 For future linear colliders the precise control and mitigation of pulse-to-pulse orbit jitter will be very important to achieve the required luminosity. Diagnostic techniques for the orbit jitter measurement and correction for multi-bunch operation are being addressed at the KEK Accelerator Test Facility 2 (ATF2). In this paper we present recent studies on the vertical jitter propagation through the ATF2 extraction line and final focus system. For these studies the vertical pulse-to-pulse position and angle jitter have been measured using the available stripline beam position monitors in the beamline. The cases with and without intra-train orbit feedback correction in the ATF2 extraction line are compared.

TUPPP092	Renovated Two-stage Bunch Compressor for the International Linear Collider	wiggler, positron, linac, 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.

TUPPR013	Design Integration and Vision Sharing for the ILC	lattice, linac, collider, damping	1837
	B. List, L. Hagge, S. Sühl, N.J. Walker, N. Welle DESY, Hamburg, Germany
	The Global Design Effort for the International Linear Collider is currently preparing the Technical Design Report, which will be released in early 2013. The starting point of a consistent and correct design is the accelerator lattice, which defines the layout of the machine. Integrating the lattice geometrically and optically provides the basis for civil engineering and conventional facilities planning and finally the cost estimate. Tools that provide three-dimensional visualization of the lattice and tunnel help to perform the design integration and allow sharing a common vision of the final accelerator. We will present the process that was established to arrive at such an integrated design and the tools that were developed to support that process by analyzing and visualizing lattice files.

TUPPR022	Traditional Final Focus System for CLIC	luminosity, lattice, collider, quadrupole	1858
	H. Garcia, A. Latina, R. Tomás CERN, Geneva, Switzerland H. Garcia UPC, Barcelona, Spain
	Next generation linear colliders needs a very strong focalisation to reach nanometer beam size at the Interaction Point. This task and the chromatic correction generated by the strong lenses is done by the Final Focus System. A traditional Final Focus System based on dedicated chromaticity correction sections is presented as an alternative for CLIC Final Focus. The scheme of the lattice is shown and some tolerances in the Final Doublet are calculated. A systematic tuning using Simplex algorithm and sextupole knobs is performed. The complete comparison to the Local Chromaticity correction scheme is presented.

TUPPR048	Short RF Pulse Linear Collider	collider, linac, klystron, wakefield	1924
	C.-J. Jing, S.P. Antipov, A. Kanareykin, P. Schoessow Euclid TechLabs, LLC, Solon, Ohio, USA M.E. Conde, W. Gai, J.G. Power ANL, Argonne, USA
	Funding: DOE SBIR program under Contractor #DE-SC0004320 In general, a high gradient is desirable for future linear collider designs because it can reduce the total linac length. More importantly, the efficiency and the cost to sustain the high gradient should also be considered in the optimization process of an overall design. In this article, we explore a parametric territory of short rf pulse, high group velocity, high frequency, and high gradient, etc., that may lead to an affordable high energy linear collider in the future.

TUPPR060	Detection of Ground Motion Effects on the Beam Trajectory at ATF2	ground-motion, quadrupole, lattice, extraction	1954
	Y. Renier, J. Pfingstner, D. Schulte, R. Tomás CERN, Geneva, Switzerland
	The ATF2 experiment is currently demonstrating the feasibility of the beam delivery system for the future linear collider. The tunning is very critical to obtain the nanometer vertical beam size at the interaction point and in the case of CLIC, ground motion effects on the beam must be corrected. In this respect, as a proof of principle of a ground motion feed forward, the ground motion effects on the beam trajectory are extracted from the beam position monitor readings.

TUPPR065	Wiggler Magnet Design Development for the ILC Damping Rings	wiggler, damping, vacuum, lattice	1969
	J.A. Crittenden, M.A. Palmer, D. L. Rubin CLASSE, Ithaca, New York, USA
	Funding: Work supported by the U.S. Department of Energy DE-SC0006506. The baseline damping ring lattice design for the International Linear Collider employs nearly 60 2.2-m-long superconducting wiggler magnets to provide the damping necessary to achieve the specified horizontal emittance. We describe the OPERA-based finite-element model developed for the 14-pole, 30-cm period, 7.62-cm gap superferric design which meets the 2.1 T peak field requirement. Transfer functions and field uniformity results are discussed. We present results for the accuracy of the optimized analytic model needed for symplectic tracking algorithms, as well as implications for the updated engineering design.

WEPPC007	Image Processing for Characterization of Surfaces of Superconducting RF Cavities	cavity, superconductivity, LabView, collider	2218
	M. Wenskat, S. Aderhold, E. Elsen, S. Karstensen, F. Schlander, L. Steder DESY, Hamburg, Germany
	Funding: ILC HiGrade Optical inspection of finished Nb superconducting RF cavities has worldwide been established as an important tool for identification of field limiting surface features. Single defects in a single cell of a 9-cell cavity may severely constrain the maximum gradient while the micro-structure in the vicinity of a welding seam could affect the quench behavior. DESY has automated the imaging of critical cavity surface areas, in particular those of high magnetic field. With resolution of ~10 μm2 the information volume is large and the systematic examination becomes a necessity. The development of image processing algorithms has been started with two goals: automatic characterization of cavity surface properties and defect detection. The former results aid the quality assessment of cavities after manufacture; the latter serves to push the gradient performance. The status and prospects of the image processing for the European XFEL and ILC will be presented.

WEPPC049	Individual RF Test Results of the Cavities Used in the First US-built ILC-type Cryomodule	cavity, cryomodule, SRF, radio-frequency	2321
	A. Hocker, A.C. Crawford, E.R. Harms, A. Lunin, D.A. Sergatskov, A.I. Sukhanov Fermilab, Batavia, USA G.V. Eremeev, R.L. Geng JLAB, Newport News, Virginia, USA J.P. Ozelis FRIB, East Lansing, USA
	Funding: Work supported in part by the U.S. Department of Energy under Contract No. DE-AC02-07CH11359. Eight 1.3-GHz, nine-cell SRF cavities have been installed in a cryomodule intended to demonstrate the ILC design goal of 31.5 MV/m. These cavities all underwent two types of individual RF testing: a low-power continuous-wave test of the “bare” cavity and a high-power pulsed test of the “dressed” cavity. Presented here is a discussion of the results from these tests and a comparison of their performance in the two configurations.

WEPPD074	Issues and Feasibility Demonstration of Positioning Closed Loop Control for the CLIC Supporting System Using a Test Mock-up with Five Degrees of Freedom	alignment, controls, feedback, collider	2696
	M. Sosin, M. Anastasopoulos, N. Chritin, J. Kemppinen, H. Mainaud Durand, V. Rude, G. Sterbini, S. griffet CERN, Geneva, Switzerland
	Since several years, CERN is studying the feasibility of building a high energy e⁺ e⁻ linear collider: the CLIC (Compact LInear Collider). One of the challenges of such a collider is the pre-alignment precision and accuracy requirement on the transverse positions of the linac components, which is typically 14 μm over a window of 200 m. To ensure the possibility of positioning within such tight constraints, CERN Beams Department’s Survey team has worked intensively at developing the methods and technology needed to achieve that objective. This paper describes activities which were performed on a test bench (mock-up) with five degrees of freedom (DOF) for the qualification of control algorithms for the CLIC supporting system active-pre-alignment. Present understanding, lessons learned (“know how”), issues of sensors noise and mechanical components nonlinearities are presented.

WEPPP068	Latest Performance Results from the FONT5 Intra-train Beam Position and Angle Feedback System at ATF2	feedback, kicker, extraction, collider	2864
	D.R. Bett, R. Apsimon, N. Blaskovic Kraljevic, P. Burrows, G.B. Christian, M.R. Davis, A. Gerbershagen, C. Perry JAI, Oxford, United Kingdom B. Constance CERN, Geneva, Switzerland J. Resta-López IFIC, Valencia, Spain
	A prototype Interaction Point beam-based feedback system for future electron-positron colliders, such as the International Linear Collider, has been designed and tested on the extraction line of the KEK Accelerator Test Facility (ATF). The FONT5 intra-train feedback system aims to stabilize the beam orbit by correcting both the position and angle jitter in the vertical plane on bunch-to-bunch time scales, providing micron-level stability at the entrance to the ATF2 final-focus system. The system comprises three stripline beam position monitors (BPMs) and two stripline kickers, custom low-latency analogue front-end BPM processors, a custom FPGA-based digital processing board with fast ADCs, and custom kicker-drive amplifiers. The latest results from beam tests at ATF2 will be presented, including the system latency and correction performance.

THEPPB012	Pressure Acoustic Waves in Positron Production Targets for Future Lepton Colliders	target, positron, photon, collider	3257
	O.S. Adeyemi, V.S. Kovalenko, L.I. Malysheva, G.A. Moortgat-Pick, A. Ushakov University of Hamburg, Hamburg, Germany A.F. Hartin DESY, Hamburg, Germany F. Staufenbiel DESY Zeuthen, Zeuthen, Germany
	Funding: This work is supported by the German Federal Ministry of Education and Research, Joint Research Project R&D Accelerator "Spin Management", contract number 05H10GUE Future high energy lepton colliders demand high luminosities to achieve its physics goals. For the electron-positron linear collider, the generation of positrons is a non-trivial problem: the positron production target has to a survive huge amount of energy deposited by the bombardment of intense beams of electrons or photons. This causes a rapid increase of the temperature in the target within a very short time period. The resulting thermal stress induces pressure waves and can substantially shorten the operating life-span of for the target material. In this work, we study linear and effects of induced stress through pressure acoustic waves using a hydrodynamic model. The survivability issue of the target is discussed.

THPPC046	Normal Conducting Radio Frequency x-band Deflecting Cavity Fabrication and Validation	alignment, cavity, electron, vacuum	3389
	R.B. Agustsson, L. Faillace, A.Y. Murokh, S. Storms RadiaBeam, Santa Monica, USA D. Alesini INFN/LNF, Frascati (Roma), Italy V.A. Dolgashev SLAC, Menlo Park, California, USA J.B. Rosenzweig UCLA, Los Angeles, California, USA V. Yakimenko BNL, Upton, Long Island, New York, USA
	Funding: U.S. DOE SBIR grant DE-FG02-05ER84370 An X-band Traveling wave Deflector mode cavity (XTD) has been developed and fabricated at Radiabeam Technologies to perform longitudinal characterization of the sub-picosecond ultra-relativistic electron beams. The device is optimized for the 100 MeV electron beam parameters at the Accelerator Test Facility (ATF) at Brookhaven National Laboratory, and is scalable to higher energies. An XTD is designed to operate at 11.424 GHz, and features short filling time, femtosecond resolution, and a small footprint. RF design, structure fabrication, cold testing results and commissioning plans are presented.

THPPD016	Construction and Measurement of Novel Adjustable Permanent Magnet Quadrupoles for CLIC	quadrupole, permanent-magnet, multipole, collider	3530
	B.J.A. Shepherd, J.A. Clarke STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom N.A. Collomb STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
	The CLIC drive beam decelerator requires 41,848 quadrupoles along its 42km length. In response to concerns over the heat load and operating costs of electromagnet systems, ASTeC in collaboration with CERN is developing adjustable permanent magnet-based quadrupoles. This novel design concept uses moving permanent magnets to adjust the quadrupole strength over a wide operating range. The design has focused not just on achieving the field strength and quality required but has also tried to make the design well suited to mass production, as the CLIC project requires 50 magnets to be completed every day for three years. Two permanent magnet quadrupole families have been designed, for the low and high energy ends of the decelerator respectively. We present the current status of the project, including construction and magnetic measurements of the first prototype.

FRYCP01	Physics Results at the LHC and Implications for Future HEP Programmes	collider, proton, luminosity, electron	4190
	R. Heuer CERN, Geneva, Switzerland
	This presentation should review the accumulated data of the TEVATRON and the first two years of LHC operation, highlighting major results and findings for high energy physics. This talk should highlight the most burning questions in high energy physics that emerged in light of these new results and discuss their implication for the planning and preparation of future accelerator projects.
	Slides FRYCP01 [14.536 MB]

Paper

Title

Other Keywords

Page

MOEPPB001

RF-breakdown Kicks at the CTF3 Two-beam Test Stand

linac, extraction, collider, acceleration

73

A. Palaia, M. Jacewicz, T. Muranaka, R.J.M.Y. Ruber, V.G. Ziemann
Uppsala University, Uppsala, Sweden
W. Farabolini
CEA/DSM/IRFU, France

The measurement of the effects of RF-breakdown on the beam in CLIC prototype accelerator structures is one of the key aspects of the CLIC two-beam acceleration scheme being addressed at the Two-beam Test Stand (TBTS) at CTF3. RF-breakdown can randomly cause energy loss and transverse kicks to the beam. Transverse kicks have been measured by means of a screen intercepting the beam after the accelerator structure. In correspondence of a RF-breakdown we detect a double beam spot which we interpret as a sudden change of the beam trajectory within a single beam pulse. To time-resolve such effect, the TBTS has been equipped with five inductive Beam Position Monitors (BPMs) and a spectrometer line to measure both relative changes of the beam trajectory and energy losses. Here we discuss the methodology used and we present the latest results of such measurements.

MOPPR065

A Low-latency Sub-micron Resolution Stripline Beam Position Monitoring System for Single-pass Beamlines

monitoring, feedback, extraction, collider

933

P. Burrows, D.R. Bett, N. Blaskovic Kraljevic, G.B. Christian, M.R. Davis, A. Gerbershagen, C. Perry
JAI, Oxford, United Kingdom
R. Apsimon, B. Constance
CERN, Geneva, Switzerland
J. Resta-López
IFIC, Valencia, Spain

A low-latency, sub-micron resolution stripline beam position monitoring system has been developed for use in single-pass beamlines. The fast analogue front-end signal processor is based on a single-stage RF down-mixer and is combined with an FPGA-based system for digitisation and further signal processing. The system has been deployed and tested with beam at the Accelerator Test Facility at KEK. Performance results are presented on the calibration, resolution and stability of the system. A detailed simulation has been developed that is able to account for the measured performance.

MOPPR066

Study of Transverse Pulse-to-Pulse Orbit Jitter at the KEK Accelerator Test Facility 2 (ATF2)

simulation, extraction, feedback, controls

936

J. Resta-López, J. Alabau-Gonzalvo
IFIC, Valencia, Spain
R. Apsimon, B. Constance, A. Gerbershagen
CERN, Geneva, Switzerland
D.R. Bett, P. Burrows, G.B. Christian, M.R. Davis, C. Perry
JAI, Oxford, United Kingdom

Funding: FPA2010-21456-C02-01
For future linear colliders the precise control and mitigation of pulse-to-pulse orbit jitter will be very important to achieve the required luminosity. Diagnostic techniques for the orbit jitter measurement and correction for multi-bunch operation are being addressed at the KEK Accelerator Test Facility 2 (ATF2). In this paper we present recent studies on the vertical jitter propagation through the ATF2 extraction line and final focus system. For these studies the vertical pulse-to-pulse position and angle jitter have been measured using the available stripline beam position monitors in the beamline. The cases with and without intra-train orbit feedback correction in the ATF2 extraction line are compared.

TUPPP092

Renovated Two-stage Bunch Compressor for the International Linear Collider

wiggler, positron, linac, 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.

TUPPR013

Design Integration and Vision Sharing for the ILC

lattice, linac, collider, damping

1837

B. List, L. Hagge, S. Sühl, N.J. Walker, N. Welle
DESY, Hamburg, Germany

The Global Design Effort for the International Linear Collider is currently preparing the Technical Design Report, which will be released in early 2013. The starting point of a consistent and correct design is the accelerator lattice, which defines the layout of the machine. Integrating the lattice geometrically and optically provides the basis for civil engineering and conventional facilities planning and finally the cost estimate. Tools that provide three-dimensional visualization of the lattice and tunnel help to perform the design integration and allow sharing a common vision of the final accelerator. We will present the process that was established to arrive at such an integrated design and the tools that were developed to support that process by analyzing and visualizing lattice files.

TUPPR022

Traditional Final Focus System for CLIC

luminosity, lattice, collider, quadrupole

1858

H. Garcia, A. Latina, R. Tomás
CERN, Geneva, Switzerland
H. Garcia
UPC, Barcelona, Spain

Next generation linear colliders needs a very strong focalisation to reach nanometer beam size at the Interaction Point. This task and the chromatic correction generated by the strong lenses is done by the Final Focus System. A traditional Final Focus System based on dedicated chromaticity correction sections is presented as an alternative for CLIC Final Focus. The scheme of the lattice is shown and some tolerances in the Final Doublet are calculated. A systematic tuning using Simplex algorithm and sextupole knobs is performed. The complete comparison to the Local Chromaticity correction scheme is presented.

TUPPR048

Short RF Pulse Linear Collider

collider, linac, klystron, wakefield

1924

C.-J. Jing, S.P. Antipov, A. Kanareykin, P. Schoessow
Euclid TechLabs, LLC, Solon, Ohio, USA
M.E. Conde, W. Gai, J.G. Power
ANL, Argonne, USA

Funding: DOE SBIR program under Contractor #DE-SC0004320
In general, a high gradient is desirable for future linear collider designs because it can reduce the total linac length. More importantly, the efficiency and the cost to sustain the high gradient should also be considered in the optimization process of an overall design. In this article, we explore a parametric territory of short rf pulse, high group velocity, high frequency, and high gradient, etc., that may lead to an affordable high energy linear collider in the future.

TUPPR060

Detection of Ground Motion Effects on the Beam Trajectory at ATF2

ground-motion, quadrupole, lattice, extraction

1954

Y. Renier, J. Pfingstner, D. Schulte, R. Tomás
CERN, Geneva, Switzerland

The ATF2 experiment is currently demonstrating the feasibility of the beam delivery system for the future linear collider. The tunning is very critical to obtain the nanometer vertical beam size at the interaction point and in the case of CLIC, ground motion effects on the beam must be corrected. In this respect, as a proof of principle of a ground motion feed forward, the ground motion effects on the beam trajectory are extracted from the beam position monitor readings.

TUPPR065

Wiggler Magnet Design Development for the ILC Damping Rings

wiggler, damping, vacuum, lattice

1969

J.A. Crittenden, M.A. Palmer, D. L. Rubin
CLASSE, Ithaca, New York, USA

Funding: Work supported by the U.S. Department of Energy DE-SC0006506.
The baseline damping ring lattice design for the International Linear Collider employs nearly 60 2.2-m-long superconducting wiggler magnets to provide the damping necessary to achieve the specified horizontal emittance. We describe the OPERA-based finite-element model developed for the 14-pole, 30-cm period, 7.62-cm gap superferric design which meets the 2.1 T peak field requirement. Transfer functions and field uniformity results are discussed. We present results for the accuracy of the optimized analytic model needed for symplectic tracking algorithms, as well as implications for the updated engineering design.

WEPPC007

Image Processing for Characterization of Surfaces of Superconducting RF Cavities

cavity, superconductivity, LabView, collider

2218

M. Wenskat, S. Aderhold, E. Elsen, S. Karstensen, F. Schlander, L. Steder
DESY, Hamburg, Germany

Funding: ILC HiGrade
Optical inspection of finished Nb superconducting RF cavities has worldwide been established as an important tool for identification of field limiting surface features. Single defects in a single cell of a 9-cell cavity may severely constrain the maximum gradient while the micro-structure in the vicinity of a welding seam could affect the quench behavior. DESY has automated the imaging of critical cavity surface areas, in particular those of high magnetic field. With resolution of ~10 μm2 the information volume is large and the systematic examination becomes a necessity. The development of image processing algorithms has been started with two goals: automatic characterization of cavity surface properties and defect detection. The former results aid the quality assessment of cavities after manufacture; the latter serves to push the gradient performance. The status and prospects of the image processing for the European XFEL and ILC will be presented.

WEPPC049

Individual RF Test Results of the Cavities Used in the First US-built ILC-type Cryomodule

cavity, cryomodule, SRF, radio-frequency

2321

A. Hocker, A.C. Crawford, E.R. Harms, A. Lunin, D.A. Sergatskov, A.I. Sukhanov
Fermilab, Batavia, USA
G.V. Eremeev, R.L. Geng
JLAB, Newport News, Virginia, USA
J.P. Ozelis
FRIB, East Lansing, USA

Funding: Work supported in part by the U.S. Department of Energy under Contract No. DE-AC02-07CH11359.
Eight 1.3-GHz, nine-cell SRF cavities have been installed in a cryomodule intended to demonstrate the ILC design goal of 31.5 MV/m. These cavities all underwent two types of individual RF testing: a low-power continuous-wave test of the “bare” cavity and a high-power pulsed test of the “dressed” cavity. Presented here is a discussion of the results from these tests and a comparison of their performance in the two configurations.

WEPPD074

Issues and Feasibility Demonstration of Positioning Closed Loop Control for the CLIC Supporting System Using a Test Mock-up with Five Degrees of Freedom

alignment, controls, feedback, collider

2696

M. Sosin, M. Anastasopoulos, N. Chritin, J. Kemppinen, H. Mainaud Durand, V. Rude, G. Sterbini, S. griffet
CERN, Geneva, Switzerland

Since several years, CERN is studying the feasibility of building a high energy e⁺ e⁻ linear collider: the CLIC (Compact LInear Collider). One of the challenges of such a collider is the pre-alignment precision and accuracy requirement on the transverse positions of the linac components, which is typically 14 μm over a window of 200 m. To ensure the possibility of positioning within such tight constraints, CERN Beams Department’s Survey team has worked intensively at developing the methods and technology needed to achieve that objective. This paper describes activities which were performed on a test bench (mock-up) with five degrees of freedom (DOF) for the qualification of control algorithms for the CLIC supporting system active-pre-alignment. Present understanding, lessons learned (“know how”), issues of sensors noise and mechanical components nonlinearities are presented.

WEPPP068

Latest Performance Results from the FONT5 Intra-train Beam Position and Angle Feedback System at ATF2

feedback, kicker, extraction, collider

2864

D.R. Bett, R. Apsimon, N. Blaskovic Kraljevic, P. Burrows, G.B. Christian, M.R. Davis, A. Gerbershagen, C. Perry
JAI, Oxford, United Kingdom
B. Constance
CERN, Geneva, Switzerland
J. Resta-López
IFIC, Valencia, Spain

A prototype Interaction Point beam-based feedback system for future electron-positron colliders, such as the International Linear Collider, has been designed and tested on the extraction line of the KEK Accelerator Test Facility (ATF). The FONT5 intra-train feedback system aims to stabilize the beam orbit by correcting both the position and angle jitter in the vertical plane on bunch-to-bunch time scales, providing micron-level stability at the entrance to the ATF2 final-focus system. The system comprises three stripline beam position monitors (BPMs) and two stripline kickers, custom low-latency analogue front-end BPM processors, a custom FPGA-based digital processing board with fast ADCs, and custom kicker-drive amplifiers. The latest results from beam tests at ATF2 will be presented, including the system latency and correction performance.

THEPPB012

Pressure Acoustic Waves in Positron Production Targets for Future Lepton Colliders

target, positron, photon, collider

3257

O.S. Adeyemi, V.S. Kovalenko, L.I. Malysheva, G.A. Moortgat-Pick, A. Ushakov
University of Hamburg, Hamburg, Germany
A.F. Hartin
DESY, Hamburg, Germany
F. Staufenbiel
DESY Zeuthen, Zeuthen, Germany

Funding: This work is supported by the German Federal Ministry of Education and Research, Joint Research Project R&D Accelerator "Spin Management", contract number 05H10GUE
Future high energy lepton colliders demand high luminosities to achieve its physics goals. For the electron-positron linear collider, the generation of positrons is a non-trivial problem: the positron production target has to a survive huge amount of energy deposited by the bombardment of intense beams of electrons or photons. This causes a rapid increase of the temperature in the target within a very short time period. The resulting thermal stress induces pressure waves and can substantially shorten the operating life-span of for the target material. In this work, we study linear and effects of induced stress through pressure acoustic waves using a hydrodynamic model. The survivability issue of the target is discussed.

THPPC046

Normal Conducting Radio Frequency x-band Deflecting Cavity Fabrication and Validation

alignment, cavity, electron, vacuum

3389

R.B. Agustsson, L. Faillace, A.Y. Murokh, S. Storms
RadiaBeam, Santa Monica, USA
D. Alesini
INFN/LNF, Frascati (Roma), Italy
V.A. Dolgashev
SLAC, Menlo Park, California, USA
J.B. Rosenzweig
UCLA, Los Angeles, California, USA
V. Yakimenko
BNL, Upton, Long Island, New York, USA

Funding: U.S. DOE SBIR grant DE-FG02-05ER84370
An X-band Traveling wave Deflector mode cavity (XTD) has been developed and fabricated at Radiabeam Technologies to perform longitudinal characterization of the sub-picosecond ultra-relativistic electron beams. The device is optimized for the 100 MeV electron beam parameters at the Accelerator Test Facility (ATF) at Brookhaven National Laboratory, and is scalable to higher energies. An XTD is designed to operate at 11.424 GHz, and features short filling time, femtosecond resolution, and a small footprint. RF design, structure fabrication, cold testing results and commissioning plans are presented.

THPPD016

Construction and Measurement of Novel Adjustable Permanent Magnet Quadrupoles for CLIC

quadrupole, permanent-magnet, multipole, collider

3530

B.J.A. Shepherd, J.A. Clarke
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
N.A. Collomb
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom

The CLIC drive beam decelerator requires 41,848 quadrupoles along its 42km length. In response to concerns over the heat load and operating costs of electromagnet systems, ASTeC in collaboration with CERN is developing adjustable permanent magnet-based quadrupoles. This novel design concept uses moving permanent magnets to adjust the quadrupole strength over a wide operating range. The design has focused not just on achieving the field strength and quality required but has also tried to make the design well suited to mass production, as the CLIC project requires 50 magnets to be completed every day for three years. Two permanent magnet quadrupole families have been designed, for the low and high energy ends of the decelerator respectively. We present the current status of the project, including construction and magnetic measurements of the first prototype.

FRYCP01

Physics Results at the LHC and Implications for Future HEP Programmes

collider, proton, luminosity, electron

4190

R. Heuer
CERN, Geneva, Switzerland

This presentation should review the accumulated data of the TEVATRON and the first two years of LHC operation, highlighting major results and findings for high energy physics. This talk should highlight the most burning questions in high energy physics that emerged in light of these new results and discuss their implication for the planning and preparation of future accelerator projects.

Slides FRYCP01 [14.536 MB]