IPAC2021 - List of Authors (Rumolo, G.)

Paper	Title	Page
TUXA03	Progress in Mastering Electron Clouds at the Large Hadron Collider	1273
	G. Iadarola, B. Bradu, L. Mether, K. Paraschou, V. Petit, G. Rumolo, L. Sabato, G. Skripka, M. Taborelli, L.J. Tavian CERN, Geneva, Switzerland K. Paraschou AUTH, Thessaloniki, Greece
	During the second operational run of the Large Hadron Collider (LHC) a bunch spacing of 25 ns was used for the first time for luminosity production. With such a spacing, electron cloud effects are much more severe than with the 50-ns spacing, which had been used in the previous run. Beam-induced conditioning of the beam chambers mitigated the e-cloud formation to an extent that allowed an effective exploitation of 25 ns beams. Nevertheless, even after years of conditioning, e-cloud effects remained very visible, affecting beam stability and beam quality, and generating strong heat loads on the beam screens of the superconducting magnets with puzzling features. In preparation for the High Luminosity LHC upgrade, remarkable progress has been made in the modeling of the e-cloud formation and of its influence on beam stability, slow losses and emittance blow up, as well as in the understanding of the underlying behavior of the beam-chamber surface. In this contribution, we describe the main experimental observations from beam operation, the outcome of laboratory analysis conducted on beam screens extracted after the run, and the main advancements in the modeling of these phenomena.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUXA03
About •	paper received ※ 19 May 2021 paper accepted ※ 12 July 2021 issue date ※ 29 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPAB210	Beam Commissioning of the New 160 MeV H⁻ Injection System of the CERN PS Booster	3116
	E. Renner, S.C.P. Albright, F. Antoniou, F. Asvesta, H. Bartosik, C. Bracco, G.P. Di Giovanni, L.O. Jorat, E.H. Maclean, M. Meddahi, B. Mikulec, T. Prebibaj, G. Rumolo, P.K. Skowroński, W.J.M. Weterings CERN, Geneva, Switzerland
	A key component to meeting the brightness targets of the LHC Injectors Upgrade (LIU) project at CERN is the new 160 MeV H⁻ charge exchange injection system into the Proton Synchrotron Booster. This system has been in beam commissioning since December 2020, optimizing the beam production schemes for tailoring different beams to the respective user-defined brightness targets. In this paper, selected measurements from the beam commissioning period are presented, characterizing the system’s flexibility to produce the required wide range of transverse emittances. The discussion focuses on the essential optimization of the injection set-up to minimize space charge driven emittance blow-up and injection errors. The results are completed by selected comparisons with multi-particle simulation models of the injection process.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB210
About •	paper received ※ 19 May 2021 paper accepted ※ 19 July 2021 issue date ※ 29 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Progress in Mastering Electron Clouds at the Large Hadron Collider

1273

G. Iadarola, B. Bradu, L. Mether, K. Paraschou, V. Petit, G. Rumolo, L. Sabato, G. Skripka, M. Taborelli, L.J. Tavian
CERN, Geneva, Switzerland
K. Paraschou
AUTH, Thessaloniki, Greece

During the second operational run of the Large Hadron Collider (LHC) a bunch spacing of 25 ns was used for the first time for luminosity production. With such a spacing, electron cloud effects are much more severe than with the 50-ns spacing, which had been used in the previous run. Beam-induced conditioning of the beam chambers mitigated the e-cloud formation to an extent that allowed an effective exploitation of 25 ns beams. Nevertheless, even after years of conditioning, e-cloud effects remained very visible, affecting beam stability and beam quality, and generating strong heat loads on the beam screens of the superconducting magnets with puzzling features. In preparation for the High Luminosity LHC upgrade, remarkable progress has been made in the modeling of the e-cloud formation and of its influence on beam stability, slow losses and emittance blow up, as well as in the understanding of the underlying behavior of the beam-chamber surface. In this contribution, we describe the main experimental observations from beam operation, the outcome of laboratory analysis conducted on beam screens extracted after the run, and the main advancements in the modeling of these phenomena.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUXA03

About •

paper received ※ 19 May 2021 paper accepted ※ 12 July 2021 issue date ※ 29 August 2021

Export •

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

WEPAB210

Beam Commissioning of the New 160 MeV H⁻ Injection System of the CERN PS Booster

3116

E. Renner, S.C.P. Albright, F. Antoniou, F. Asvesta, H. Bartosik, C. Bracco, G.P. Di Giovanni, L.O. Jorat, E.H. Maclean, M. Meddahi, B. Mikulec, T. Prebibaj, G. Rumolo, P.K. Skowroński, W.J.M. Weterings
CERN, Geneva, Switzerland

A key component to meeting the brightness targets of the LHC Injectors Upgrade (LIU) project at CERN is the new 160 MeV H⁻ charge exchange injection system into the Proton Synchrotron Booster. This system has been in beam commissioning since December 2020, optimizing the beam production schemes for tailoring different beams to the respective user-defined brightness targets. In this paper, selected measurements from the beam commissioning period are presented, characterizing the system’s flexibility to produce the required wide range of transverse emittances. The discussion focuses on the essential optimization of the injection set-up to minimize space charge driven emittance blow-up and injection errors. The results are completed by selected comparisons with multi-particle simulation models of the injection process.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB210

About •

paper received ※ 19 May 2021 paper accepted ※ 19 July 2021 issue date ※ 29 August 2021

Export •

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