IPAC2016 - List of Authors (Dobbins, J.)

Paper	Title	Page
TUPOR031	Trapped Ion Effects and Mitigation During High Current Operation in the Cornell DC Photoinjector	1735
SUPSS054	use link to see paper's listing under its alternate paper code
	S.J. Full, A.C. Bartnik, I.V. Bazarov, J. Dobbins, B.M. Dunham, G.H. Hoffstaetter Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: U.S. Department of Energy (Grant No. DE-SC0012493), National Science Foundation (Award No. NSF-DMR 0807731) The Cornell high intensity photoinjector reaches a new regime of linac beam parameters where high continuous-wave electron beam currents lead to ion trapping. Above 10 mA, we have observed beam trips that limit stable machine operation to approximately 10^-15 minutes. By applying known ion clearing methods, the machine lifetime increases to at least 24 hours of continuous operation, suggesting that trapped ions are the most likely cause of the trips. In this paper we share some of our observations ion trapping in the photoinjector, as well as experimental tests of three common ion mitigation methods: clearing electrodes, beam shaking and bunch gaps.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR031
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WEPMR022	ERL Main Linac Cryomodule Cavity Performance and Effect of Thermal Cycling	2312
	F. Furuta, J. Dobbins, R.G. Eichhorn, G.M. Ge, D. Gonnella, G.H. Hoffstaetter, M. Liepe, T.I. O'Connell, P. Quigley, D.M. Sabol, J. Sears, E.N. Smith, V. Veshcherevich Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Cornell has designed, fabricated, and tested a high current (100 mA) CW SRF prototype cryomodule for the future energy-recovery linac (ERL) based synchrotron-light facility at Cornell . It houses six 7-cell SRF cavities with individual HOM absorbers and one magnet/ BPM section. Cavities are targeted to operate with high Qo of 2.0·10¹⁰ at 16.2 MV/m, 1.8 K in continuous wave (CW) mode. We will report the RF test results of 7-cell cavities in this cryomodule after initial cooldown and several thermal cycles with different cooldown method.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR022
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

TUPOR031

Trapped Ion Effects and Mitigation During High Current Operation in the Cornell DC Photoinjector

1735

SUPSS054

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

S.J. Full, A.C. Bartnik, I.V. Bazarov, J. Dobbins, B.M. Dunham, G.H. Hoffstaetter
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: U.S. Department of Energy (Grant No. DE-SC0012493), National Science Foundation (Award No. NSF-DMR 0807731)
The Cornell high intensity photoinjector reaches a new regime of linac beam parameters where high continuous-wave electron beam currents lead to ion trapping. Above 10 mA, we have observed beam trips that limit stable machine operation to approximately 10^-15 minutes. By applying known ion clearing methods, the machine lifetime increases to at least 24 hours of continuous operation, suggesting that trapped ions are the most likely cause of the trips. In this paper we share some of our observations ion trapping in the photoinjector, as well as experimental tests of three common ion mitigation methods: clearing electrodes, beam shaking and bunch gaps.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOR031

Export •

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

WEPMR022

ERL Main Linac Cryomodule Cavity Performance and Effect of Thermal Cycling

2312

F. Furuta, J. Dobbins, R.G. Eichhorn, G.M. Ge, D. Gonnella, G.H. Hoffstaetter, M. Liepe, T.I. O'Connell, P. Quigley, D.M. Sabol, J. Sears, E.N. Smith, V. Veshcherevich
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Cornell has designed, fabricated, and tested a high current (100 mA) CW SRF prototype cryomodule for the future energy-recovery linac (ERL) based synchrotron-light facility at Cornell . It houses six 7-cell SRF cavities with individual HOM absorbers and one magnet/ BPM section. Cavities are targeted to operate with high Qo of 2.0·10¹⁰ at 16.2 MV/m, 1.8 K in continuous wave (CW) mode. We will report the RF test results of 7-cell cavities in this cryomodule after initial cooldown and several thermal cycles with different cooldown method.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMR022

Export •

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