IPAC2016 - List of Authors (Yin Vallgren, C.)

Paper	Title	Page
THPMW033	Operational Experience of the Upgraded LHC Injection Kicker Magnets	3623
	M.J. Barnes, A. Adraktas, G. Bregliozzi, S. Calatroni, H.A. Day, L. Ducimetière, B. Goddard, V. Gomes Namora, V. Mertens, B. Salvant, J.A. Uythoven, L. Vega Cid, W.J.M. Weterings, C. Yin Vallgren CERN, Geneva, Switzerland
	During Run 1 of the LHC the injection kicker magnets caused occasional operational delays due to beam induced heating with high bunch intensity and short bunch lengths. In addition, sometimes there were also sporadic issues with microscopic unidentified falling objects, vacuum activity and electrical flashover of the injection kickers. An extensive program of studies was launched and significant upgrades were carried out during long shutdown 1. These upgrades include a new design of a beam screen to both reduce the beam coupling impedance of the kicker magnet, and to significantly reduce the electric field associated with the screen conductors, hence decreasing the probability of electrical breakdown in this region. In addition new cleaning procedures were implemented and equipment adjacent to the injection kickers and various vacuum components were modified. This paper presents operational experience of the injection kicker magnets during Run 2 of the LHC and assesses the effectiveness of the various upgrades.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMW033
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THPMY010	LHC Beam Vacuum Evolution During 2015 Machine Operation	3673
	C. Yin Vallgren, G. Bregliozzi, P. Chiggiato CERN, Geneva, Switzerland
	The LHC successfully returned to operation in April, 2015 after almost 2 years of Long Shutdown 1 (LS1) for various upgrade and consolidation programs. During 2015 operation, the LHC operated for more than 1000 fills. The 2015 LHC proton physics ended with 2244 bunches per beam circulating with 25 ns bunch spacing at top energy of 6.5 TeV. This paper summarizes the dynamic vacuum observations in different locations along the LHC during dedicated fills as well as during physics runs with both 50 ns and 25 ns bunch spacing. The causes for the dynamic pressure rises are investigated and are presented. A clear beam conditioning effect is observed, as well as a so-called de-conditioning effect. Furthermore, for the experimental areas, the dynamic pressure evolution is also presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY010
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Operational Experience of the Upgraded LHC Injection Kicker Magnets

3623

M.J. Barnes, A. Adraktas, G. Bregliozzi, S. Calatroni, H.A. Day, L. Ducimetière, B. Goddard, V. Gomes Namora, V. Mertens, B. Salvant, J.A. Uythoven, L. Vega Cid, W.J.M. Weterings, C. Yin Vallgren
CERN, Geneva, Switzerland

During Run 1 of the LHC the injection kicker magnets caused occasional operational delays due to beam induced heating with high bunch intensity and short bunch lengths. In addition, sometimes there were also sporadic issues with microscopic unidentified falling objects, vacuum activity and electrical flashover of the injection kickers. An extensive program of studies was launched and significant upgrades were carried out during long shutdown 1. These upgrades include a new design of a beam screen to both reduce the beam coupling impedance of the kicker magnet, and to significantly reduce the electric field associated with the screen conductors, hence decreasing the probability of electrical breakdown in this region. In addition new cleaning procedures were implemented and equipment adjacent to the injection kickers and various vacuum components were modified. This paper presents operational experience of the injection kicker magnets during Run 2 of the LHC and assesses the effectiveness of the various upgrades.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMW033

Export •

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

THPMY010

LHC Beam Vacuum Evolution During 2015 Machine Operation

3673

C. Yin Vallgren, G. Bregliozzi, P. Chiggiato
CERN, Geneva, Switzerland

The LHC successfully returned to operation in April, 2015 after almost 2 years of Long Shutdown 1 (LS1) for various upgrade and consolidation programs. During 2015 operation, the LHC operated for more than 1000 fills. The 2015 LHC proton physics ended with 2244 bunches per beam circulating with 25 ns bunch spacing at top energy of 6.5 TeV. This paper summarizes the dynamic vacuum observations in different locations along the LHC during dedicated fills as well as during physics runs with both 50 ns and 25 ns bunch spacing. The causes for the dynamic pressure rises are investigated and are presented. A clear beam conditioning effect is observed, as well as a so-called de-conditioning effect. Furthermore, for the experimental areas, the dynamic pressure evolution is also presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMY010

Export •

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