IPAC2018 - List of Authors (Whitehead, M.)

Paper	Title	Page
TUPAL057	Preliminary Experiments in Caesium Delivery and Gettering on the ISIS Vespa Source	1144
	T. M. Sarmento, R.E. Abel, D.C. Faircloth, S.R. Lawrie, J.H. Macgregor, M. Whitehead, T. Wood STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	Caesium capture by graphite at various temperatures 20- 300°C in the VESPA ion source test stand was explored in a preliminary experiment. An accompanying experiment was set up to evaluate the control of caesium boiler delivery in the various ISIS penning sources. Results indicate Cs flux fluctuates at constant settings, which must be accounted for to interpret graphite gettering results. Future studies to identify the cause of fluctuations are considered, and a more rigorous experiment to study the use of graphite is introduced.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL057
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THPML059	Re-Commissioning the Front End Test Stand Negative Hydrogen Ion Source, Beam Transport and Interlocks	4769
	S.R. Lawrie, R.E. Abel, M. Dudman, D.C. Faircloth, A.P. Letchford, J.H. Macgregor, M. Perkins, T. M. Sarmento, R.C. Searle, M. Whitehead, T. Wood STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	The front end test stand (FETS) is a demonstrator for a future high intensity, high duty factor negative hydrogen (H') ion injector. With the radio-frequency quadrupole (RFQ) nearing installation, the ion source has been re-commissioned in preparation for long-term operation. The 3 MeV beam exceeds the radio-activation energy of common engineering materials, so radiation shielding has been erected. A new interlocking scheme has been signed-off which integrates the existing ion source high voltage area with the new shielding access points, to ensure that the machine can operate safely during beam production. The existing vacuum arrangement has been extended to in-clude the RFQ and medium energy beam transport (MEBT) line. A new programmable logic controller (PLC) has been built to operate the entire vacuum chain. The ion source high voltage equipment has been upgraded to minimise both spark rate and intensity. A collimating aperture and Faraday cup have been installed after the low energy beam transport (LEBT) section to ensure the beam is well aligned for injection into the RFQ. Re-commissioning the ion source has given a rugged shakedown of all these new systems before beam is required for the RFQ. *scott.lawrie@stfc.ac.uk
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML059
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Paper

Title

Page

Preliminary Experiments in Caesium Delivery and Gettering on the ISIS Vespa Source

1144

T. M. Sarmento, R.E. Abel, D.C. Faircloth, S.R. Lawrie, J.H. Macgregor, M. Whitehead, T. Wood
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

Caesium capture by graphite at various temperatures 20- 300°C in the VESPA ion source test stand was explored in a preliminary experiment. An accompanying experiment was set up to evaluate the control of caesium boiler delivery in the various ISIS penning sources. Results indicate Cs flux fluctuates at constant settings, which must be accounted for to interpret graphite gettering results. Future studies to identify the cause of fluctuations are considered, and a more rigorous experiment to study the use of graphite is introduced.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL057

Export •

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

THPML059

Re-Commissioning the Front End Test Stand Negative Hydrogen Ion Source, Beam Transport and Interlocks

4769

S.R. Lawrie, R.E. Abel, M. Dudman, D.C. Faircloth, A.P. Letchford, J.H. Macgregor, M. Perkins, T. M. Sarmento, R.C. Searle, M. Whitehead, T. Wood
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

The front end test stand (FETS) is a demonstrator for a future high intensity, high duty factor negative hydrogen (H') ion injector. With the radio-frequency quadrupole (RFQ) nearing installation, the ion source has been re-commissioned in preparation for long-term operation. The 3 MeV beam exceeds the radio-activation energy of common engineering materials, so radiation shielding has been erected. A new interlocking scheme has been signed-off which integrates the existing ion source high voltage area with the new shielding access points, to ensure that the machine can operate safely during beam production. The existing vacuum arrangement has been extended to in-clude the RFQ and medium energy beam transport (MEBT) line. A new programmable logic controller (PLC) has been built to operate the entire vacuum chain. The ion source high voltage equipment has been upgraded to minimise both spark rate and intensity. A collimating aperture and Faraday cup have been installed after the low energy beam transport (LEBT) section to ensure the beam is well aligned for injection into the RFQ. Re-commissioning the ion source has given a rugged shakedown of all these new systems before beam is required for the RFQ.
*scott.lawrie@stfc.ac.uk

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML059

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