Testing of HOM coupler designs on a single cell niobium cavity
Abstract
Coaxial higher order mode (HOM) couplers were developed initially for HERA cavities and subsequently for TESLA cavities. They were adopted later for SNS and Jlab upgrade cavities. The principle of operation is the rejection of the fundamental mode by the tunable filter and the transmission of the HOMs. It has been recognized recently that for continuous wave or high duty factor applications of the TESLA coupler the output pick-up probe must stay superconducting in order to avoid its heating by the fundamental mode residual magnetic field leading to deterioration of the cavity quality factor. In addition, the thermal conduction of existing rf feedthrough designs is only marginally sufficient to keep even the niobium probe tip superconducting in cw operation. We have equipped a single-cell niobium cavity with the modified HOM couplers and tested the new designs by measuring Q vs Eacc behavior at 2 K for different feedthroughs and probe tip materials.
- Authors:
- Publication Date:
- Research Org.:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Org.:
- USDOE; USDOE Office of Energy Research (ER) (US)
- OSTI Identifier:
- 839999
- Report Number(s):
- JLAB-ACC-05-344; DOE/ER/40150-3361
TRN: US0501763
- DOE Contract Number:
- AC05-84ER40150
- Resource Type:
- Conference
- Resource Relation:
- Conference: PAC 2005, Knoxville, TN (US), 05/16/2005--05/20/2005; Other Information: PBD: 1 May 2005
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 43 PARTICLE ACCELERATORS; SUPERCONDUCTING CAVITY RESONATORS; MAGNETIC FIELDS; NIOBIUM; QUALITY FACTOR; TESTING; THERMAL CONDUCTION; ACCELERATORS
Citation Formats
Kneisel, Peter, Ciovati, Gianluigi, myneni, ganapati rao, Wu, Genfa, and Sekutowicz, Jacek. Testing of HOM coupler designs on a single cell niobium cavity. United States: N. p., 2005.
Web.
Kneisel, Peter, Ciovati, Gianluigi, myneni, ganapati rao, Wu, Genfa, & Sekutowicz, Jacek. Testing of HOM coupler designs on a single cell niobium cavity. United States.
Kneisel, Peter, Ciovati, Gianluigi, myneni, ganapati rao, Wu, Genfa, and Sekutowicz, Jacek. 2005.
"Testing of HOM coupler designs on a single cell niobium cavity". United States. https://www.osti.gov/servlets/purl/839999.
@article{osti_839999,
title = {Testing of HOM coupler designs on a single cell niobium cavity},
author = {Kneisel, Peter and Ciovati, Gianluigi and myneni, ganapati rao and Wu, Genfa and Sekutowicz, Jacek},
abstractNote = {Coaxial higher order mode (HOM) couplers were developed initially for HERA cavities and subsequently for TESLA cavities. They were adopted later for SNS and Jlab upgrade cavities. The principle of operation is the rejection of the fundamental mode by the tunable filter and the transmission of the HOMs. It has been recognized recently that for continuous wave or high duty factor applications of the TESLA coupler the output pick-up probe must stay superconducting in order to avoid its heating by the fundamental mode residual magnetic field leading to deterioration of the cavity quality factor. In addition, the thermal conduction of existing rf feedthrough designs is only marginally sufficient to keep even the niobium probe tip superconducting in cw operation. We have equipped a single-cell niobium cavity with the modified HOM couplers and tested the new designs by measuring Q vs Eacc behavior at 2 K for different feedthroughs and probe tip materials.},
doi = {},
url = {https://www.osti.gov/biblio/839999},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun May 01 00:00:00 EDT 2005},
month = {Sun May 01 00:00:00 EDT 2005}
}