Involvement of hydrogen-vacancy complexes in the baking effect of niobium cavities

May 1, 2010
7 pages
Published in:
  • Phys.Rev.ST Accel.Beams 13 (2010) 052002

Citations per year

20112014201720202023012345
Abstract: (APS)
Baking is necessary to improve high accelerating gradient performances of superconducting niobium cavities. Ten years after this discovery in 1998, the understanding of this effect still resists a lot of theoretical explanations. For the first time, positron annihilation spectroscopy performed on niobium samples reveals the increase after baking of positrons trapped under the Nb surface. Presence of hydrogen-vacancy complexes and their dissociation by baking could both explain rf losses observed at high fields (Q drop) and its cure (baking effect).
  • 84.40.-x
  • 74.70.Ad
  • 78.70.Bj
  • 74.62.Dh