In situ SRF cavity processing using optical ionization of gases

Legg, Robert; Powers, Thomas H.

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DOE OSTI · 1735314

In situ SRF cavity processing using optical ionization of gases

Legg, Robert·Powers, Thomas H.

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Abstract

A system and method for the in situ processing of internal SRF cavity surfaces to reduce field emission and improve maximum gradient. An electromagnetic radiation source is introduced in the bore of a superconducting cavity to enhance ionization or dissociation of gases which then remove contaminants from the surface of the cavity, either through direct surface bombardment, chemical reaction or through the production of radiation which interacts with the contaminants. An RF or low frequency electromagnetic field may be established in the cavity which further enhances the ionization or dissociation process and may cause the ions to bombard sites with enhanced electric fields. The invention removes the requirement that the RF field be sufficient by itself to ionize gas in the cavity.

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Legg, Robert, Powers, Thomas H.. 2020-09-29. In situ SRF cavity processing using optical ionization of gases. https://www.osti.gov/biblio/1735314

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