HB2012 - List of Authors (Goddard, B.)

Paper

Title

Page

Beam Stability and Tail Population at SPS Scrapers

166

L.N. Drøsdal, K. Cornelis, B. Goddard, V. Kain, M. Meddahi, Ö. Mete, B. Mikulec, E. Veyrunes
CERN, Geneva, Switzerland

Before injection into the LHC the beams are scraped in the SPS to remove the tails of the transverse particle distributions. Without scraping the tail population is large enough to create losses above the beam abort thresholds of the LHC beam loss monitor system when injecting. The scrapers are only effective if correctly set up. This paper shows the results of periodical scraper scans. The beam position and beam size at the scraper is changing with time. The scraper settings hence need to follow accordingly. The scans also give insight into the transverse tail population and could therefore provide useful beam quality diagnostics. The impact on new scraper designs and setting up strategy are discussed.

TUO1A01

The High Intensity/High Brightness Upgrade Program at CERN: Status and Challenges

226

S.S. Gilardoni, G. Arduini, T. Argyropoulos, S. Aumon, H. Bartosik, E. Benedetto, N. Biancacci, T. Bohl, J. Borburgh, C. Carli, F. Caspers, H. Damerau, J.F. Esteban Müller, V. Forte, R. Garoby, M. Giovannozzi, B. Goddard, S. Hancock, K. Hanke, A. Huschauer, G. Iadarola, M. Meddahi, G. Métral, B. Mikulec, E. Métral, Y. Papaphilippou, S. Persichelli, G. Rumolo, B. Salvant, F. Schmidt, E.N. Shaposhnikova, R. Steerenberg, G. Sterbini, M. Taborelli, H. Timko, M. Vretenar, R. Wasef, C. Yin Vallgren, C. Zannini
CERN, Geneva, Switzerland
G. Franchetti
GSI, Darmstadt, Germany
M. Migliorati
University of Rome "La Sapienza", Rome, Italy
A.Y. Molodozhentsev
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
M.T.F. Pivi
SLAC, Menlo Park, California, USA
V.G. Vaccaro
Naples University Federico II, Mathematical, Physical and Natural Sciences Faculty, Napoli, Italy

The future beam brilliance and intensities required by the HL-LHC (High-Luminosity LHC) project and for possible new neutrino production beams triggered a deep revision of the LHC injector performances. The analysis, progressing in the framework of the LHC Injectors Upgrade (LIU) projects, outlined major limitations mainly related to collective effects - space charge in PSB and PS, electron cloud driven and TMCI instabilities in the SPS, longitudinal coupled bunch instabilities in the PS for example - but also to the existing hardware capability to cope with beam instabilities and losses. A summary of the observations and simulation studies carried out so far, as well as the future ones, will be presented. The solution proposed to overcome the different limitations and the plans for their implementation will be also briefly reviewed.

Slides TUO1A01 [12.748 MB]

WEO1A02

LHC Impedance Model: Experience with High Intensity Operation in the LHC

349

B. Salvant, O. Aberle, G. Arduini, R.W. Aßmann, V. Baglin, M.J. Barnes, P. Baudrenghien, A. Bertarelli, C. Bracco, R. Bruce, X. Buffat, F. Carra, F. Caspers, G. Cattenoz, S.D. Claudet, H.A. Day, J.F. Esteban Müller, M. Garlaschè, L. Gentini, B. Goddard, A. Grudiev, B. Henrist, W. Herr, S. Jakobsen, R.J. Jones, G. Lanza, L. Lari, T. Mastoridis, N. Mounet, E. Métral, A.A. Nosych, J.L. Nougaret, S. Persichelli, T. Pieloni, A.M. Piguiet, S. Redaelli, F. Roncarolo, G. Rumolo, B. Salvachua, M. Sapinski, E.N. Shaposhnikova, L.J. Tavian, M.A. Timmins, J.A. Uythoven, A. Vidal, R. Wasef, D. Wollmann
CERN, Geneva, Switzerland
A.V. Burov
Fermilab, Batavia, USA
S.M. White
BNL, Upton, Long Island, New York, USA

The CERN Large Hadron Collider (LHC) is now in luminosity production mode and has been pushing its performance in the past months by increasing the proton beam brightness, the collision energy and the machine availability. As a consequence, collective effects have started to become more and more visible and have effectively slowed down the performance increase of the machine. Among these collective effects, the interaction of brighter LHC bunches with the longitudinal and transverse impedance of the machine has been observed to generate beam induced heating and transverse instabilities since 2010. This contribution reviews the current LHC impedance model obtained from theory, simulations and bench measurements as well as a selection of measured effects with the LHC beam.

Slides WEO1A02 [7.991 MB]

Paper	Title	Page
MOP247	Beam Stability and Tail Population at SPS Scrapers	166
	L.N. Drøsdal, K. Cornelis, B. Goddard, V. Kain, M. Meddahi, Ö. Mete, B. Mikulec, E. Veyrunes CERN, Geneva, Switzerland
	Before injection into the LHC the beams are scraped in the SPS to remove the tails of the transverse particle distributions. Without scraping the tail population is large enough to create losses above the beam abort thresholds of the LHC beam loss monitor system when injecting. The scrapers are only effective if correctly set up. This paper shows the results of periodical scraper scans. The beam position and beam size at the scraper is changing with time. The scraper settings hence need to follow accordingly. The scans also give insight into the transverse tail population and could therefore provide useful beam quality diagnostics. The impact on new scraper designs and setting up strategy are discussed.

TUO1A01	The High Intensity/High Brightness Upgrade Program at CERN: Status and Challenges	226
	S.S. Gilardoni, G. Arduini, T. Argyropoulos, S. Aumon, H. Bartosik, E. Benedetto, N. Biancacci, T. Bohl, J. Borburgh, C. Carli, F. Caspers, H. Damerau, J.F. Esteban Müller, V. Forte, R. Garoby, M. Giovannozzi, B. Goddard, S. Hancock, K. Hanke, A. Huschauer, G. Iadarola, M. Meddahi, G. Métral, B. Mikulec, E. Métral, Y. Papaphilippou, S. Persichelli, G. Rumolo, B. Salvant, F. Schmidt, E.N. Shaposhnikova, R. Steerenberg, G. Sterbini, M. Taborelli, H. Timko, M. Vretenar, R. Wasef, C. Yin Vallgren, C. Zannini CERN, Geneva, Switzerland G. Franchetti GSI, Darmstadt, Germany M. Migliorati University of Rome "La Sapienza", Rome, Italy A.Y. Molodozhentsev J-PARC, KEK & JAEA, Ibaraki-ken, Japan M.T.F. Pivi SLAC, Menlo Park, California, USA V.G. Vaccaro Naples University Federico II, Mathematical, Physical and Natural Sciences Faculty, Napoli, Italy
	The future beam brilliance and intensities required by the HL-LHC (High-Luminosity LHC) project and for possible new neutrino production beams triggered a deep revision of the LHC injector performances. The analysis, progressing in the framework of the LHC Injectors Upgrade (LIU) projects, outlined major limitations mainly related to collective effects - space charge in PSB and PS, electron cloud driven and TMCI instabilities in the SPS, longitudinal coupled bunch instabilities in the PS for example - but also to the existing hardware capability to cope with beam instabilities and losses. A summary of the observations and simulation studies carried out so far, as well as the future ones, will be presented. The solution proposed to overcome the different limitations and the plans for their implementation will be also briefly reviewed.
	Slides TUO1A01 [12.748 MB]

WEO1A02	LHC Impedance Model: Experience with High Intensity Operation in the LHC	349
	B. Salvant, O. Aberle, G. Arduini, R.W. Aßmann, V. Baglin, M.J. Barnes, P. Baudrenghien, A. Bertarelli, C. Bracco, R. Bruce, X. Buffat, F. Carra, F. Caspers, G. Cattenoz, S.D. Claudet, H.A. Day, J.F. Esteban Müller, M. Garlaschè, L. Gentini, B. Goddard, A. Grudiev, B. Henrist, W. Herr, S. Jakobsen, R.J. Jones, G. Lanza, L. Lari, T. Mastoridis, N. Mounet, E. Métral, A.A. Nosych, J.L. Nougaret, S. Persichelli, T. Pieloni, A.M. Piguiet, S. Redaelli, F. Roncarolo, G. Rumolo, B. Salvachua, M. Sapinski, E.N. Shaposhnikova, L.J. Tavian, M.A. Timmins, J.A. Uythoven, A. Vidal, R. Wasef, D. Wollmann CERN, Geneva, Switzerland A.V. Burov Fermilab, Batavia, USA S.M. White BNL, Upton, Long Island, New York, USA
	The CERN Large Hadron Collider (LHC) is now in luminosity production mode and has been pushing its performance in the past months by increasing the proton beam brightness, the collision energy and the machine availability. As a consequence, collective effects have started to become more and more visible and have effectively slowed down the performance increase of the machine. Among these collective effects, the interaction of brighter LHC bunches with the longitudinal and transverse impedance of the machine has been observed to generate beam induced heating and transverse instabilities since 2010. This contribution reviews the current LHC impedance model obtained from theory, simulations and bench measurements as well as a selection of measured effects with the LHC beam.
	Slides WEO1A02 [7.991 MB]