IPAC2014 - List of Authors (Grudiev, A.)

Paper	Title	Page
TUPME008	Status of the CLIC-UK R&D Programme on Design of Key Systems for the Compact Linear Collider	1354
	P. Burrows, R. Ainsworth, T. Aumeyr, D.R. Bett, N. Blaskovic Kraljevic, L.M. Bobb, S.T. Boogert, A. Bosco, G.B. Christian, L. Corner, F.J. Cullinan, M.R. Davis, D. Gamba, P. Karataev, K.O. Kruchinin, A. Lyapin, L.J. Nevay, C. Perry, J. Roberts, J. Snuverink, J.R. Towler JAI, Egham, Surrey, United Kingdom R. Ainsworth, T. Aumeyr, S.T. Boogert, A. Bosco, P. Karataev, K.O. Kruchinin, L.J. Nevay, J.R. Towler Royal Holloway, University of London, Surrey, United Kingdom P.K. Ambattu, G. Burt, A.C. Dexter, M. Jenkins, S. Karimian, C. Lingwood, B.J. Woolley Cockcroft Institute, Lancaster University, Lancaster, United Kingdom L.M. Bobb, R. Corsini, D. Gamba, A. Grudiev, A. Latina, T. Lefèvre, C. Marrelli, M. Modena, J. Roberts, H. Schmickler, D. Schulte, P.K. Skowroński, J. Snuverink, S. Stapnes, F. Tecker, R. Tomás, R. Wegner, M. Wendt, W. Wuensch CERN, Geneva, Switzerland J.A. Clarke, S.P. Jamison, P.A. McIntosh, B.J.A. Shepherd STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom N.A. Collomb, D.G. Stokes STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom L. Corner Oxford University, Physics Department, Oxford, Oxon, United Kingdom W.A. Gillespie, R. Pan, M.A. Tyrk, D.A. Walsh University of Dundee, Nethergate, Dundee, Scotland, United Kingdom R.M. Jones UMAN, Manchester, United Kingdom
	Six UK institutes are engaged in a collaborative R&D programme with CERN aimed at demonstrating key aspects of technology feasibility for the Compact Linear Collider (CLIC). We give an overview and status of the R&D being done on: 1) Drive-beam components: quadrupole magnets and the beam phase feed-forward prototype. 2) Beam instrumentation: stripline and cavity beam position monitors, an electro-optical longitudinal bunch profile monitor, and laserwire and diffraction and transition radiation monitors for transverse beam-size determination. 3) Beam delivery system and machine-detector interface design, including beam feedback/control systems and crab cavity design and control. 4) RF structure design. In each case, where applicable, we report on the status of prototype systems and performance tests with beam at the CTF3, ATF2 and CesrTA test facilities, including plans for future experiments.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME008
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TUPRI014	Modelling and Long Term Dynamics of Crab Cavities in the LHC	1578
	R. Appleby, D.R. Brett UMAN, Manchester, United Kingdom J. Barranco García, R. De Maria, A. Grudiev, R. Tomás CERN, Geneva, Switzerland
	Funding: The research leading to these results has received funding from the European Commission under the FP7 project HiLumi LHC, GA no. 284404, co-funded by the DoE, USA and KEK, Japan. The High Luminosity upgrade of the Large Hadron Collider (HL-LHC) aims to achieve an integrated luminosity of 250-300 fb-1 per year. This upgrade includes the use crab cavities to mitigate the geometric loss of luminosity arising from the beam crossing angle. The tight space constraints at the location of the cavities leads to cavity designs which are axially non-symmetric and have a potentially significant effect on the long term dynamics and dynamic aperture of the LHC. In this paper we present the current status of advanced modelling of crab cavities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI014
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TUPRI049	Geometric Beam Coupling Impedance of LHC Secondary Collimators	1677
SUSPSNE059	use link to see paper's listing under its alternate paper code
	O. Frasciello, S. Tomassini, M. Zobov INFN/LNF, Frascati (Roma), Italy A. Grudiev, N. Mounet, B. Salvant CERN, Geneva, Switzerland
	Funding: Work supported by European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404 The High Luminosity LHC project is aimed at increasing the LHC luminosity by an order of magnitude. One of the key ingredients to achieve the luminosity goal is the beam intensity increase. In order to keep under control beam instabilities and to avoid excessive power losses a careful design of new vacuum chamber components and an improvement of the present LHC impedance model are required. Collimators are the main impedance contributors. Measurements with beam have revealed that the betatron coherent tune shifts were by about a factor of 2 higher with respect to the theoretical predictions based on the current model. Up to now the resistive wall impedance has been considered as the major impedance contribution for collimators. By carefully simulating their geometric impedance we show that for the graphite collimators with half-gaps higher than 10 mm the geometric impedance exceeds the resistive wall one. In turn, for the tungsten collimators the geometric impedance dominates for all used gap values. Hence, including the geometric collimator impedance into the LHC impedance model enabled us to reach a better agreement between the measured and simulated collimator tune shifts.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI049
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WEOCA02	Recent Results from CTF3 Two Beam Test Stand	1880
	W. Farabolini, F. Peauger CEA/DSM/IRFU, France Ch. Borgmann, J. Ögren, R.J.M.Y. Ruber Uppsala University, Uppsala, Sweden R. Corsini, D. Gamba, A. Grudiev, M.A. Khan, S. Mazzoni, J.L. Navarro Quirante, R. Pan, J.R. Towler, N. Vitoratou, K. Yaqub CERN, Geneva, Switzerland
	From mid-2012, the Two Beam Test Stand (TBTS) in the CTF3 Experimental Facility is hosting 2 high gradient accelerating structures powered by a single power extraction and transfer structure in a scheme very close to the CLIC basic cell. We report here about the results obtained with this configuration as: energy gain and energy spread in relation with RF phases and power, octupolar transverse beam effects compared with modeling predictions, breakdown rate and breakdown locations within the structures. These structures are the first to be fitted with Wake Field Monitors (WFM) that have been extensively tested and used to further improve the structures alignment on the beam line. These results show the unique capabilities of this test stand to conduct experiments with real beams.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEOCA02
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WEPME015	High-gradient Test Results from a CLIC Prototype Accelerating Structure: TD26CC	2285
	W. Wuensch, A. Degiovanni, S. Döbert, W. Farabolini, A. Grudiev, J.W. Kovermann, E. Montesinos, G. Riddone, I. Syratchev, R. Wegner CERN, Geneva, Switzerland A. Solodko JINR, Dubna, Moscow Region, Russia B.J. Woolley Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
	The CLIC study has progressively tested prototype accelerating structures which incorporate an ever increasing number of features which are needed for a final version installed in a linear collider. The most recent high power test made in the CERN X-band test stand, Xbox-1, is a of a CERN-built prototype which includes damping features but also compact input and output power couplers, which maximize the overall length to active gradient ratio of the structure. The structure’s high-gradient performance, 100 MV/m and low breakdown rate, matches previously tested structures validating both CERN fabrication and the compact coupler design.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPME015
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THPME081	Plans for an Australian XFEL Using a CLIC X-band Linac	3424
	M.J. Boland, T.K. Charles, R.T. Dowd, G. LeBlanc, Y.E. Tan, K.P. Wootton, D. Zhu SLSA, Clayton, Australia R. Corsini, A. Grudiev, A. Latina, D. Schulte, S. Stapnes, I. Syratchev, W. Wuensch CERN, Geneva, Switzerland
	Preliminary plans are presented for a sub-Angstrom wavelength XFEL at the Australian Synchrotron light source site. The design is based around a 6 GeV x-band linac from the CLIC Project. One of the motivations for the design is to have an XFEL co-located on the site with existing storage ring based synchrotron light source. The desire and ability of the Australian photon science community to win beamtime on existing XFELs has lead to this design study to plan for a future machine in Australia. The technology choice is also driven by the Australian participation in the CLIC Collaboration and the local HEP community.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME081
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Paper

Title

Page

Status of the CLIC-UK R&D Programme on Design of Key Systems for the Compact Linear Collider

1354

P. Burrows, R. Ainsworth, T. Aumeyr, D.R. Bett, N. Blaskovic Kraljevic, L.M. Bobb, S.T. Boogert, A. Bosco, G.B. Christian, L. Corner, F.J. Cullinan, M.R. Davis, D. Gamba, P. Karataev, K.O. Kruchinin, A. Lyapin, L.J. Nevay, C. Perry, J. Roberts, J. Snuverink, J.R. Towler
JAI, Egham, Surrey, United Kingdom
R. Ainsworth, T. Aumeyr, S.T. Boogert, A. Bosco, P. Karataev, K.O. Kruchinin, L.J. Nevay, J.R. Towler
Royal Holloway, University of London, Surrey, United Kingdom
P.K. Ambattu, G. Burt, A.C. Dexter, M. Jenkins, S. Karimian, C. Lingwood, B.J. Woolley
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
L.M. Bobb, R. Corsini, D. Gamba, A. Grudiev, A. Latina, T. Lefèvre, C. Marrelli, M. Modena, J. Roberts, H. Schmickler, D. Schulte, P.K. Skowroński, J. Snuverink, S. Stapnes, F. Tecker, R. Tomás, R. Wegner, M. Wendt, W. Wuensch
CERN, Geneva, Switzerland
J.A. Clarke, S.P. Jamison, P.A. McIntosh, B.J.A. Shepherd
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
N.A. Collomb, D.G. Stokes
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
L. Corner
Oxford University, Physics Department, Oxford, Oxon, United Kingdom
W.A. Gillespie, R. Pan, M.A. Tyrk, D.A. Walsh
University of Dundee, Nethergate, Dundee, Scotland, United Kingdom
R.M. Jones
UMAN, Manchester, United Kingdom

Six UK institutes are engaged in a collaborative R&D programme with CERN aimed at demonstrating key aspects of technology feasibility for the Compact Linear Collider (CLIC). We give an overview and status of the R&D being done on: 1) Drive-beam components: quadrupole magnets and the beam phase feed-forward prototype. 2) Beam instrumentation: stripline and cavity beam position monitors, an electro-optical longitudinal bunch profile monitor, and laserwire and diffraction and transition radiation monitors for transverse beam-size determination. 3) Beam delivery system and machine-detector interface design, including beam feedback/control systems and crab cavity design and control. 4) RF structure design. In each case, where applicable, we report on the status of prototype systems and performance tests with beam at the CTF3, ATF2 and CesrTA test facilities, including plans for future experiments.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME008

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPRI014

Modelling and Long Term Dynamics of Crab Cavities in the LHC

1578

R. Appleby, D.R. Brett
UMAN, Manchester, United Kingdom
J. Barranco García, R. De Maria, A. Grudiev, R. Tomás
CERN, Geneva, Switzerland

Funding: The research leading to these results has received funding from the European Commission under the FP7 project HiLumi LHC, GA no. 284404, co-funded by the DoE, USA and KEK, Japan.
The High Luminosity upgrade of the Large Hadron Collider (HL-LHC) aims to achieve an integrated luminosity of 250-300 fb-1 per year. This upgrade includes the use crab cavities to mitigate the geometric loss of luminosity arising from the beam crossing angle. The tight space constraints at the location of the cavities leads to cavity designs which are axially non-symmetric and have a potentially significant effect on the long term dynamics and dynamic aperture of the LHC. In this paper we present the current status of advanced modelling of crab cavities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI014

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPRI049

Geometric Beam Coupling Impedance of LHC Secondary Collimators

1677

SUSPSNE059

use link to see paper's listing under its alternate paper code

O. Frasciello, S. Tomassini, M. Zobov
INFN/LNF, Frascati (Roma), Italy
A. Grudiev, N. Mounet, B. Salvant
CERN, Geneva, Switzerland

Funding: Work supported by European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404
The High Luminosity LHC project is aimed at increasing the LHC luminosity by an order of magnitude. One of the key ingredients to achieve the luminosity goal is the beam intensity increase. In order to keep under control beam instabilities and to avoid excessive power losses a careful design of new vacuum chamber components and an improvement of the present LHC impedance model are required. Collimators are the main impedance contributors. Measurements with beam have revealed that the betatron coherent tune shifts were by about a factor of 2 higher with respect to the theoretical predictions based on the current model. Up to now the resistive wall impedance has been considered as the major impedance contribution for collimators. By carefully simulating their geometric impedance we show that for the graphite collimators with half-gaps higher than 10 mm the geometric impedance exceeds the resistive wall one. In turn, for the tungsten collimators the geometric impedance dominates for all used gap values. Hence, including the geometric collimator impedance into the LHC impedance model enabled us to reach a better agreement between the measured and simulated collimator tune shifts.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI049

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOCA02

Recent Results from CTF3 Two Beam Test Stand

1880

W. Farabolini, F. Peauger
CEA/DSM/IRFU, France
Ch. Borgmann, J. Ögren, R.J.M.Y. Ruber
Uppsala University, Uppsala, Sweden
R. Corsini, D. Gamba, A. Grudiev, M.A. Khan, S. Mazzoni, J.L. Navarro Quirante, R. Pan, J.R. Towler, N. Vitoratou, K. Yaqub
CERN, Geneva, Switzerland

From mid-2012, the Two Beam Test Stand (TBTS) in the CTF3 Experimental Facility is hosting 2 high gradient accelerating structures powered by a single power extraction and transfer structure in a scheme very close to the CLIC basic cell. We report here about the results obtained with this configuration as: energy gain and energy spread in relation with RF phases and power, octupolar transverse beam effects compared with modeling predictions, breakdown rate and breakdown locations within the structures. These structures are the first to be fitted with Wake Field Monitors (WFM) that have been extensively tested and used to further improve the structures alignment on the beam line. These results show the unique capabilities of this test stand to conduct experiments with real beams.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEOCA02

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPME015

High-gradient Test Results from a CLIC Prototype Accelerating Structure: TD26CC

2285

W. Wuensch, A. Degiovanni, S. Döbert, W. Farabolini, A. Grudiev, J.W. Kovermann, E. Montesinos, G. Riddone, I. Syratchev, R. Wegner
CERN, Geneva, Switzerland
A. Solodko
JINR, Dubna, Moscow Region, Russia
B.J. Woolley
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom

The CLIC study has progressively tested prototype accelerating structures which incorporate an ever increasing number of features which are needed for a final version installed in a linear collider. The most recent high power test made in the CERN X-band test stand, Xbox-1, is a of a CERN-built prototype which includes damping features but also compact input and output power couplers, which maximize the overall length to active gradient ratio of the structure. The structure’s high-gradient performance, 100 MV/m and low breakdown rate, matches previously tested structures validating both CERN fabrication and the compact coupler design.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPME015

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPME081

Plans for an Australian XFEL Using a CLIC X-band Linac

3424

M.J. Boland, T.K. Charles, R.T. Dowd, G. LeBlanc, Y.E. Tan, K.P. Wootton, D. Zhu
SLSA, Clayton, Australia
R. Corsini, A. Grudiev, A. Latina, D. Schulte, S. Stapnes, I. Syratchev, W. Wuensch
CERN, Geneva, Switzerland

Preliminary plans are presented for a sub-Angstrom wavelength XFEL at the Australian Synchrotron light source site. The design is based around a 6 GeV x-band linac from the CLIC Project. One of the motivations for the design is to have an XFEL co-located on the site with existing storage ring based synchrotron light source. The desire and ability of the Australian photon science community to win beamtime on existing XFELs has lead to this design study to plan for a future machine in Australia. The technology choice is also driven by the Australian participation in the CLIC Collaboration and the local HEP community.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME081

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)