IPAC2016 - List of Authors (Kalliokoski, M.K.)

Paper	Title	Page
TUPMW023	Macroparticle-Induced Losses During 6.5 TeV LHC Operation	1481
	G. Papotti, M. Albert, B. Auchmann, E.B. Holzer, M.K. Kalliokoski, A. Lechner CERN, Geneva, Switzerland
	One of the major performance limitations for operating the LHC at high energy was feared to be the so called UFOs (Unidentified Falling Objects, presumably micrometer sized dust particles which lead to fast beam losses when they interact with the beam). Indeed much higher rates were observed in 2015 compared to Run 1, and about 20 fills were prematurely terminated by too high losses caused by such events. Additionally they triggered a few beam induced quenches at high energy, the first in the history of the LHC. In this paper we review the latest update on the analysis of these events, e.g. the conditioning observed during the year and possible correlations with beam and machine parameters. At the same time we also review the optimization of beam loss monitor thresholds in terms of machine protection and availability.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW023
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TUPMW028	Bound-Free Pair Production in LHC Pb-Pb Operation at 6.37 Z TeV per Beam	1497
	J.M. Jowett, B. Auchmann, C. Bahamonde Castro, M.K. Kalliokoski, A. Lechner, T. Mertens, M. Schaumann, C. Xu CERN, Geneva, Switzerland
	In the 2015 Pb-Pb collision run of the LHC, the power of the secondary beams emitted from the interaction point by the bound-free pair production process reached new levels while the propensity of the bending magnets to quench is higher at the new magnetic field levels. This beam power is about 70 times greater than that contained in the luminosity debris and is focussed on a specific location. As long foreseen, orbit bumps were introduced in the dispersion suppressors around the highest luminosity experiments to mitigate the risk by displacing and spreading out these losses. An experiment designed to induce quenches and determine the quench levels and luminosity limit was carried out to assess the need for special collimators to intercept these secondary beams.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW028
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Paper

Title

Page

Macroparticle-Induced Losses During 6.5 TeV LHC Operation

1481

G. Papotti, M. Albert, B. Auchmann, E.B. Holzer, M.K. Kalliokoski, A. Lechner
CERN, Geneva, Switzerland

One of the major performance limitations for operating the LHC at high energy was feared to be the so called UFOs (Unidentified Falling Objects, presumably micrometer sized dust particles which lead to fast beam losses when they interact with the beam). Indeed much higher rates were observed in 2015 compared to Run 1, and about 20 fills were prematurely terminated by too high losses caused by such events. Additionally they triggered a few beam induced quenches at high energy, the first in the history of the LHC. In this paper we review the latest update on the analysis of these events, e.g. the conditioning observed during the year and possible correlations with beam and machine parameters. At the same time we also review the optimization of beam loss monitor thresholds in terms of machine protection and availability.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW023

Export •

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

TUPMW028

Bound-Free Pair Production in LHC Pb-Pb Operation at 6.37 Z TeV per Beam

1497

J.M. Jowett, B. Auchmann, C. Bahamonde Castro, M.K. Kalliokoski, A. Lechner, T. Mertens, M. Schaumann, C. Xu
CERN, Geneva, Switzerland

In the 2015 Pb-Pb collision run of the LHC, the power of the secondary beams emitted from the interaction point by the bound-free pair production process reached new levels while the propensity of the bending magnets to quench is higher at the new magnetic field levels. This beam power is about 70 times greater than that contained in the luminosity debris and is focussed on a specific location. As long foreseen, orbit bumps were introduced in the dispersion suppressors around the highest luminosity experiments to mitigate the risk by displacing and spreading out these losses. An experiment designed to induce quenches and determine the quench levels and luminosity limit was carried out to assess the need for special collimators to intercept these secondary beams.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW028

Export •

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