IPAC2017 - List of Authors (Schaumann, M.)

Paper	Title	Page
TUPIK087	Phase Advance Interlocking Throughout the Whole LHC Cycle	1901
	K. Fuchsberger, A. Calia, M.A. Galilée, G.H. Hemelsoet, M. Hostettler, D. Jacquet, J. Makai, M. Schaumann CERN, Geneva, Switzerland
	Each beam of CERN's Large Hadron Collider (LHC) stores 360 MJ at design energy and design intensity. In the unlikely event of an asynchronous beam dump, not all particles would be extracted immediately. They would still take one turn around the ring, oscillating with potentially high amplitudes. In case the beam would hit one of the experimental detectors or the collimators close to the interaction points, severe damage could occur. In order to minimize the risk during such a scenario, a new interlock system was put in place in 2016. This system guarantees a phase advance of zero degrees (within tolerances) between the extraction kicker and the interaction point. This contribution describes the motivation for this new system as well as the technical implementation and the strategies used to derive appropriate tolerances to allow sufficient protection without risking false beam dump triggers.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPIK087
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TUPVA013	Lifetime of Asymmetric Colliding Beams in the LHC	2067
	J.M. Jowett, R. Alemany-Fernández, M.A. Jebramcik, T. Mertens, M. Schaumann CERN, Geneva, Switzerland
	In the 2013 proton-nucleus (p-Pb) run of the LHC, the lifetime of the lead beam was significantly shorter than could be accounted for by luminosity burn-off. These effects were observed at a lower level in 2016 and studied in more detail. The beams were not only asymmetric but the differences in the bunch filling schemes between protons and Pb nuclei led to a wide variety of beam-beam interaction sequences in the bunch trains. The colliding bunches were also of different sizes. We present an analysis of the data and an interpretation in terms of theoretical models.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA013
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TUPVA014	The 2016 Proton-Nucleus Run of the LHC	2071
	J.M. Jowett, R. Alemany-Fernández, G. Baud, P. Baudrenghien, R. De Maria, R. De Maria, D. Jacquet, M.A. Jebramcik, A. Mereghetti, T. Mertens, M. Schaumann, H. Timko, M. Wendt, J. Wenninger CERN, Geneva, Switzerland
	For five of the LHC experiments the second p-Pb collision run planned in 2016 offered the opportunity to answer a range of important physics questions arising from the surprise discoveries (e.g., flow-like collective phenomena in small systems) made in earlier Pb-Pb, p-Pb and p-p runs. However the diversity of the physics and their respective capabilities led them to request very different operating conditions, in terms of collision energy, luminosity and pile-up. These appeared mutually incompatible within the available one month of operation. Nevertheless, a plan to satisfy most requirements was developed and implemented successfully. It exploited different beam lifetimes at two beam energies of 4 Z TeV and 6.5 Z TeV, a variety of luminosity sharing and bunch filling schemes, and varying beam directions. The outcome of this very complex strategy for repeated re-commissioning and operation of the LHC included the longest ever LHC fill with luminosity levelled for almost 38 h. The peak luminosity achieved exceeded the design value by a factor 7.8 and integrated luminosity substantially exceeded the experiments' requests.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA014
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TUPVA128	Performance of the CERN Injector Complex and Transmission Studies into the LHC during the Second Proton-Lead Run	2395
	R. Alemany-Fernández, S.C.P. Albright, M.E. Angoletta, J. Axensalva, W. Bartmann, H. Bartosik, P. Baudrenghien, G. Bellodi, A. Blas, T. Bohl, E. Carlier, S. Cettour-Cave, K. Cornelis, H. Damerau, A. Findlay, S.S. Gilardoni, S. Hancock, A. Huschauer, M.A. Jebramcik, S. Jensen, J.M. Jowett, V. Kain, D. Küchler, A.M. Lombardi, D. Manglunki, T. Mertens, M. O'Neil, S. Pasinelli, Á. Saá Hernández, M. Schaumann, R. Scrivens, R. Steerenberg, H. Timko, V. Toivanen, G. Tranquille, F.M. Velotti, F.J.C. Wenander, J. Wenninger CERN, Geneva, Switzerland
	The LHC performance during the proton-lead run in 2016 fully relied on a permanent monitoring and systematic improvement of the beam quality in all the injectors. The beam production and characteristics are explained in this paper, together with the improvements realized during the run from the source up to the flat top of the LHC. Transmission studies from one accelerator to the next as well as beam quality evolution studies during the cycle at each accelerator, have been carried out and are summarized in this paper. In 2016, the LHC had to deliver the beams to the experiments at two different energies, 4 Z TeV and 6.5 Z TeV. The properties of the beams at these two energies are also presented
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA128
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Paper

Title

Page

Phase Advance Interlocking Throughout the Whole LHC Cycle

1901

K. Fuchsberger, A. Calia, M.A. Galilée, G.H. Hemelsoet, M. Hostettler, D. Jacquet, J. Makai, M. Schaumann
CERN, Geneva, Switzerland

Each beam of CERN's Large Hadron Collider (LHC) stores 360 MJ at design energy and design intensity. In the unlikely event of an asynchronous beam dump, not all particles would be extracted immediately. They would still take one turn around the ring, oscillating with potentially high amplitudes. In case the beam would hit one of the experimental detectors or the collimators close to the interaction points, severe damage could occur. In order to minimize the risk during such a scenario, a new interlock system was put in place in 2016. This system guarantees a phase advance of zero degrees (within tolerances) between the extraction kicker and the interaction point. This contribution describes the motivation for this new system as well as the technical implementation and the strategies used to derive appropriate tolerances to allow sufficient protection without risking false beam dump triggers.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPIK087

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TUPVA013

Lifetime of Asymmetric Colliding Beams in the LHC

2067

J.M. Jowett, R. Alemany-Fernández, M.A. Jebramcik, T. Mertens, M. Schaumann
CERN, Geneva, Switzerland

In the 2013 proton-nucleus (p-Pb) run of the LHC, the lifetime of the lead beam was significantly shorter than could be accounted for by luminosity burn-off. These effects were observed at a lower level in 2016 and studied in more detail. The beams were not only asymmetric but the differences in the bunch filling schemes between protons and Pb nuclei led to a wide variety of beam-beam interaction sequences in the bunch trains. The colliding bunches were also of different sizes. We present an analysis of the data and an interpretation in terms of theoretical models.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA013

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

TUPVA014

The 2016 Proton-Nucleus Run of the LHC

2071

J.M. Jowett, R. Alemany-Fernández, G. Baud, P. Baudrenghien, R. De Maria, R. De Maria, D. Jacquet, M.A. Jebramcik, A. Mereghetti, T. Mertens, M. Schaumann, H. Timko, M. Wendt, J. Wenninger
CERN, Geneva, Switzerland

For five of the LHC experiments the second p-Pb collision run planned in 2016 offered the opportunity to answer a range of important physics questions arising from the surprise discoveries (e.g., flow-like collective phenomena in small systems) made in earlier Pb-Pb, p-Pb and p-p runs. However the diversity of the physics and their respective capabilities led them to request very different operating conditions, in terms of collision energy, luminosity and pile-up. These appeared mutually incompatible within the available one month of operation. Nevertheless, a plan to satisfy most requirements was developed and implemented successfully. It exploited different beam lifetimes at two beam energies of 4 Z TeV and 6.5 Z TeV, a variety of luminosity sharing and bunch filling schemes, and varying beam directions. The outcome of this very complex strategy for repeated re-commissioning and operation of the LHC included the longest ever LHC fill with luminosity levelled for almost 38 h. The peak luminosity achieved exceeded the design value by a factor 7.8 and integrated luminosity substantially exceeded the experiments' requests.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA014

Export •

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

TUPVA128

Performance of the CERN Injector Complex and Transmission Studies into the LHC during the Second Proton-Lead Run

2395

R. Alemany-Fernández, S.C.P. Albright, M.E. Angoletta, J. Axensalva, W. Bartmann, H. Bartosik, P. Baudrenghien, G. Bellodi, A. Blas, T. Bohl, E. Carlier, S. Cettour-Cave, K. Cornelis, H. Damerau, A. Findlay, S.S. Gilardoni, S. Hancock, A. Huschauer, M.A. Jebramcik, S. Jensen, J.M. Jowett, V. Kain, D. Küchler, A.M. Lombardi, D. Manglunki, T. Mertens, M. O'Neil, S. Pasinelli, Á. Saá Hernández, M. Schaumann, R. Scrivens, R. Steerenberg, H. Timko, V. Toivanen, G. Tranquille, F.M. Velotti, F.J.C. Wenander, J. Wenninger
CERN, Geneva, Switzerland

The LHC performance during the proton-lead run in 2016 fully relied on a permanent monitoring and systematic improvement of the beam quality in all the injectors. The beam production and characteristics are explained in this paper, together with the improvements realized during the run from the source up to the flat top of the LHC. Transmission studies from one accelerator to the next as well as beam quality evolution studies during the cycle at each accelerator, have been carried out and are summarized in this paper. In 2016, the LHC had to deliver the beams to the experiments at two different energies, 4 Z TeV and 6.5 Z TeV. The properties of the beams at these two energies are also presented

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPVA128

Export •

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