Field-dependent surface resistance for superconducting niobium accelerating cavities
نویسندگان
چکیده
منابع مشابه
Surface Superconductivity in Niobium for Superconducting RF Cavities
A systematic study is presented on the superconductivity (sc) parameters of the ultrapure niobium used for the fabrication of the nine-cell 1.3 GHz cavities for the linear collider project TESLA. Cylindrical Nb samples have been subjected to the same surface treatments that are applied to the TESLA cavities: buffered chemical polishing (BCP), electrolytic polishing (EP), low-temperature bakeout...
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Field emission and thermal breakdown are the main mechanisms limiting the accelerating gradient of niobium radio-frequency cavities. Diagnostic tools to study these mechanisms include quality measurements, thermometry, and microscopy. Results presented here demonstrate that micron-size, conducting particles are the source of field emission. Thermal breakdown is caused by a variety of defects su...
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ژورنال
عنوان ژورنال: Physical Review Special Topics - Accelerators and Beams
سال: 2011
ISSN: 1098-4402
DOI: 10.1103/physrevstab.14.101002