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RIS citation export for THPAL033: Measurement of the Internal Dark Current in a High Gradient Accelerator Structure at 17 GHz

TY - CONF
AU - Xu, H.
AU - Shapiro, M.A.
AU - Temkin, R.J.
ED - Koscielniak, Shane
ED - Satogata, Todd
ED - Schaa, Volker RW
ED - Thomson, Jana
TI - Measurement of the Internal Dark Current in a High Gradient Accelerator Structure at 17 GHz
J2 - Proc. of IPAC2018, Vancouver, BC, Canada, April 29-May 4, 2018
C1 - Vancouver, BC, Canada
T2 - International Particle Accelerator Conference
T3 - 9
LA - english
AB - We report a study of internal dark current generation by multipactor inside a 17 GHz single cell standing wave disk-loaded waveguide accelerator structure. The multipactor takes place on the side wall of the central cell, driven by the local rf electric and magnetic fields. Theory indicates that a resonant multipactor mode with two rf cycles can be excited near 45 MV/m gradient and a single rf cycle multipactor mode near 60 MV/m. The accelerator structure had two thin slits opened on the side wall of the central cell to directly extract and measure the internal dark current. The dark current was measured as a function of the gradient up to a gradient of 70 MV/m. The experimental results agreed well with theory, showing the two predicted multipactor modes. To further study the effect of the central cell side wall surface properties on the structure performance, we prepared and tested a second structure with the central cell side wall coated with a layer of diamond-like carbon. The comparison of the results showed that the coating reduced the internal dark current and thus enhanced the structure performance considerably.
PB - JACoW Publishing
CP - Geneva, Switzerland
SP - 3705
EP - 3708
KW - multipactoring
KW - acceleration
KW - electron
KW - experiment
KW - simulation
DA - 2018/06
PY - 2018
SN - 978-3-95450-184-7
DO - 10.18429/JACoW-IPAC2018-THPAL033
UR - http://jacow.org/ipac2018/papers/thpal033.pdf
ER -