IPAC2016 - List of Authors (Cruikshank, P.)

Paper	Title	Page
MOPOY058	Removing Known SPS Intensity Limitations for High Luminosity LHC Goals	989
	E.N. Shaposhnikova, T. Argyropoulos, T. Bohl, P. Cruikshank, B. Goddard, T. Kaltenbacher, A. Lasheen, J. Perez Espinos, J. Repond, B. Salvant, C. Vollinger CERN, Geneva, Switzerland
	In preparation of the SPS as an LHC injector its impedance was significantly reduced in 1999 - 2000. A new SPS impedance reduction campaign is planned now for the High Luminosity (HL)-LHC project, which requires bunch intensities twice as high as the nominal one. One of the known intensity limitations is a longitudinal multi-bunch instability with a threshold 3 times below this operational intensity. The instability is presently cured using the 4th harmonic RF system and controlled emittance blow-up, but reaching the HL-LHC parameters cannot be assured without improving the machine impedance. Recently the impedance sources responsible for this instability were identified and implementation of their shielding and damping is foreseen during the next long shutdown (2019 - 2020) in synergy with two other important upgrades: amorphous carbon coating of (part of) the vacuum chamber against the e-cloud effect and rearrangement of the 200 MHz RF system. In this paper the strategy of impedance reduction is presented together with beam intensity achievable after its realisation. The potential effect of other proposals on remaining limitations is also considered.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY058
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Removing Known SPS Intensity Limitations for High Luminosity LHC Goals

989

E.N. Shaposhnikova, T. Argyropoulos, T. Bohl, P. Cruikshank, B. Goddard, T. Kaltenbacher, A. Lasheen, J. Perez Espinos, J. Repond, B. Salvant, C. Vollinger
CERN, Geneva, Switzerland

In preparation of the SPS as an LHC injector its impedance was significantly reduced in 1999 - 2000. A new SPS impedance reduction campaign is planned now for the High Luminosity (HL)-LHC project, which requires bunch intensities twice as high as the nominal one. One of the known intensity limitations is a longitudinal multi-bunch instability with a threshold 3 times below this operational intensity. The instability is presently cured using the 4th harmonic RF system and controlled emittance blow-up, but reaching the HL-LHC parameters cannot be assured without improving the machine impedance. Recently the impedance sources responsible for this instability were identified and implementation of their shielding and damping is foreseen during the next long shutdown (2019 - 2020) in synergy with two other important upgrades: amorphous carbon coating of (part of) the vacuum chamber against the e-cloud effect and rearrangement of the 200 MHz RF system. In this paper the strategy of impedance reduction is presented together with beam intensity achievable after its realisation. The potential effect of other proposals on remaining limitations is also considered.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY058

Export •

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