SRF2021 - List of Authors (Atieh, S.)

Paper	Title	Page
MOPCAV016	HOM Couplers and RF Antennas for HL-LHC Crab Cavities: Developments for Manufacturing	303
	S. Barrière, S. Atieh, B. Bulat, R. Calaga, S.J. Calvo, O. Capatina, T. Demazière, G. Favre, A. Gallifa Terricabras, M. Garlasché, J.-M. Geisser, J.A. Mitchell, E. Montesinos, F. Motschmann, P. Naisson, R. Ninet, L. Prever-Loiri, L.R.A. Renaglia, K. Scibor, N. Villanti CERN, Meyrin, Switzerland
	Superconducting RF crab cavities are being manufactured as part of the HL-LHC upgrade at CERN. Amongst its related ancillaries, radiofrequency HOM (High Order Modes) suppressors and field antennas are essential for reaching nominal performance during operation with high energy beams, as they monitor and control the electromagnetic fields in the cavities. Several concepts of such equipment have been engineered and manufactured, for both design validation and RF performance assessment. The following paper highlights manufacturing process definition, its challenges and the assembly strategies focusing on the ongoing RFD prototypes for the SPS beam tests. Specific tooling development and test campaigns are also described.
	Poster MOPCAV016 [1.457 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPCAV016
About •	Received ※ 21 June 2021 — Revised ※ 10 July 2021 — Accepted ※ 11 November 2021 — Issue date ※ 18 November 2021
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPTEV009	Seamless 1.3 GHz Copper Cavities for Nb Coatings: Cold Test Results of Two Different Approaches	498
	L. Vega Cid, S. Atieh, L.M.A. Ferreira, L. Laín-Amador, C. Pereira Carlos, G.J. Rosaz, K. Scibor, W. Venturini Delsolaro, P. Vidal García CERN, Meyrin, Switzerland S.B. Leith University Siegen, Siegen, Germany
	A necessary condition for high SRF performances in thin film coated cavities is the absence of substrate defects. For instance, in the past, defects originated around electron beam welds in high magnetic field areas have been shown to be the cause of performance limitations in Nb/Cu cavities. Seamless cavities are therefore good candidates to allow an optimization of the coating parameters without the pitfalls of a changing substrate. In this work, we present the first results of two different methods to produce seamless cavities applied to 1.3 GHz copper single cells coated with thin Nb films by means of HIPIMS. A first method consists in electroplating the copper resonator on precisely machined aluminum mandrels, which are then dissolved chemically. As an alternative and a cross check, one cavity was machined directly from the bulk. Both cavities were coated with HIPIMS Nb films using the same coating parameters and the SRF performance was measured down to 1.8 K with a variable coupler to minimize the measurement uncertainty.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPTEV009
About •	Received ※ 21 June 2021 — Revised ※ 28 October 2021 — Accepted ※ 18 November 2021 — Issue date ※ 10 February 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

HOM Couplers and RF Antennas for HL-LHC Crab Cavities: Developments for Manufacturing

303

S. Barrière, S. Atieh, B. Bulat, R. Calaga, S.J. Calvo, O. Capatina, T. Demazière, G. Favre, A. Gallifa Terricabras, M. Garlasché, J.-M. Geisser, J.A. Mitchell, E. Montesinos, F. Motschmann, P. Naisson, R. Ninet, L. Prever-Loiri, L.R.A. Renaglia, K. Scibor, N. Villanti
CERN, Meyrin, Switzerland

Superconducting RF crab cavities are being manufactured as part of the HL-LHC upgrade at CERN. Amongst its related ancillaries, radiofrequency HOM (High Order Modes) suppressors and field antennas are essential for reaching nominal performance during operation with high energy beams, as they monitor and control the electromagnetic fields in the cavities. Several concepts of such equipment have been engineered and manufactured, for both design validation and RF performance assessment. The following paper highlights manufacturing process definition, its challenges and the assembly strategies focusing on the ongoing RFD prototypes for the SPS beam tests. Specific tooling development and test campaigns are also described.

Poster MOPCAV016 [1.457 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-MOPCAV016

About •

Received ※ 21 June 2021 — Revised ※ 10 July 2021 — Accepted ※ 11 November 2021 — Issue date ※ 18 November 2021

Cite •

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

TUPTEV009

Seamless 1.3 GHz Copper Cavities for Nb Coatings: Cold Test Results of Two Different Approaches

498

L. Vega Cid, S. Atieh, L.M.A. Ferreira, L. Laín-Amador, C. Pereira Carlos, G.J. Rosaz, K. Scibor, W. Venturini Delsolaro, P. Vidal García
CERN, Meyrin, Switzerland
S.B. Leith
University Siegen, Siegen, Germany

A necessary condition for high SRF performances in thin film coated cavities is the absence of substrate defects. For instance, in the past, defects originated around electron beam welds in high magnetic field areas have been shown to be the cause of performance limitations in Nb/Cu cavities. Seamless cavities are therefore good candidates to allow an optimization of the coating parameters without the pitfalls of a changing substrate. In this work, we present the first results of two different methods to produce seamless cavities applied to 1.3 GHz copper single cells coated with thin Nb films by means of HIPIMS. A first method consists in electroplating the copper resonator on precisely machined aluminum mandrels, which are then dissolved chemically. As an alternative and a cross check, one cavity was machined directly from the bulk. Both cavities were coated with HIPIMS Nb films using the same coating parameters and the SRF performance was measured down to 1.8 K with a variable coupler to minimize the measurement uncertainty.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-TUPTEV009

About •

Received ※ 21 June 2021 — Revised ※ 28 October 2021 — Accepted ※ 18 November 2021 — Issue date ※ 10 February 2022

Cite •

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