IPAC2019 - List of Authors (Paszkiewicz, J.)

Paper	Title	Page
WEPRB062	Spatially Resolved Dark Current in High Gradient Traveling Wave Structures	2956
SUSPFO106	use link to see paper's listing under its alternate paper code
	J. Paszkiewicz, W. Wuensch CERN, Meyrin, Switzerland P. Burrows JAI, Oxford, United Kingdom P. Burrows Oxford University, Physics Department, Oxford, Oxon, United Kingdom
	High-gradient accelerating structures are known to produce field-emitted current from regions of high surface field, which are captured and accelerated by the fields within the structure. This current is routinely measured in structures under test in the CLIC high-gradient test stands using Faraday cups. This paper presents a novel technique to spatially resolve the longitudinal distribution of field emitted current by analysing downstream Faraday cup signals when the structure is fed with RF pulses much shorter than its filling time. Results from this method applied to X-band cavities operating at 100 MV/m are presented, and are compared to breakdown position distributions. A decay in emitted current as conditioning progressed in regions with a low breakdown rate and large jumps in regions with a large breakdown rate are observed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPRB062
About •	paper received ※ 29 April 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPRB059	Dark Current Analysis at CERN’s X-band Facility	2944
	D. Banon-Caballero, M. Boronat, V. Sánchez Sebastián, A. Vnuchenko IFIC, Valencia, Spain N. Catalán Lasheras, S. Pitman, M. Widorski, W. Wuensch, V. del Pozo Romano CERN, Meyrin, Switzerland A. Faus-Golfe LAL, Orsay, France B. Gimeno UVEG, Burjasot (Valencia), Spain T.G. Lucas, M. Volpi The University of Melbourne, Melbourne, Victoria, Australia W.L. Millar Lancaster University, Lancaster, United Kingdom J. Paszkiewicz University of Oxford, Oxford, United Kingdom
	Dark current is particularly relevant during operation in high-gradient linear accelerators. Resulting from the capture of field emitted electrons, dark current produces additional radiation that needs to be accounted for in experiments. In this paper, an analysis of dark current is presented for four accelerating structures that were tested and conditioned in CERN’s X-band test facility for CLIC. The dependence on power, and therefore on accelerating gradient, of the dark current signals is presented. The Fowler-Nordheim equation for field emission seems to be in accordance with the experimental data. Moreover, the analysis shows that the current intensity decreases as a function of time due to conditioning, but discrete jumps in the dark current signals are present, probably caused by breakdown events that change the emitters’ location and intensity.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPRB059
About •	paper received ※ 10 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

WEPRB062

Spatially Resolved Dark Current in High Gradient Traveling Wave Structures

2956

SUSPFO106

use link to see paper's listing under its alternate paper code

J. Paszkiewicz, W. Wuensch
CERN, Meyrin, Switzerland
P. Burrows
JAI, Oxford, United Kingdom
P. Burrows
Oxford University, Physics Department, Oxford, Oxon, United Kingdom

High-gradient accelerating structures are known to produce field-emitted current from regions of high surface field, which are captured and accelerated by the fields within the structure. This current is routinely measured in structures under test in the CLIC high-gradient test stands using Faraday cups. This paper presents a novel technique to spatially resolve the longitudinal distribution of field emitted current by analysing downstream Faraday cup signals when the structure is fed with RF pulses much shorter than its filling time. Results from this method applied to X-band cavities operating at 100 MV/m are presented, and are compared to breakdown position distributions. A decay in emitted current as conditioning progressed in regions with a low breakdown rate and large jumps in regions with a large breakdown rate are observed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPRB062

About •

paper received ※ 29 April 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019

Export •

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

WEPRB059

Dark Current Analysis at CERN’s X-band Facility

2944

D. Banon-Caballero, M. Boronat, V. Sánchez Sebastián, A. Vnuchenko
IFIC, Valencia, Spain
N. Catalán Lasheras, S. Pitman, M. Widorski, W. Wuensch, V. del Pozo Romano
CERN, Meyrin, Switzerland
A. Faus-Golfe
LAL, Orsay, France
B. Gimeno
UVEG, Burjasot (Valencia), Spain
T.G. Lucas, M. Volpi
The University of Melbourne, Melbourne, Victoria, Australia
W.L. Millar
Lancaster University, Lancaster, United Kingdom
J. Paszkiewicz
University of Oxford, Oxford, United Kingdom

Dark current is particularly relevant during operation in high-gradient linear accelerators. Resulting from the capture of field emitted electrons, dark current produces additional radiation that needs to be accounted for in experiments. In this paper, an analysis of dark current is presented for four accelerating structures that were tested and conditioned in CERN’s X-band test facility for CLIC. The dependence on power, and therefore on accelerating gradient, of the dark current signals is presented. The Fowler-Nordheim equation for field emission seems to be in accordance with the experimental data. Moreover, the analysis shows that the current intensity decreases as a function of time due to conditioning, but discrete jumps in the dark current signals are present, probably caused by breakdown events that change the emitters’ location and intensity.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPRB059

About •

paper received ※ 10 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019

Export •

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