No more CKY two-forms in the NHEK
arXiv:1110.3872 · doi:10.1088/0264-9381/29/4/045004
Abstract
We show that in the near-horizon limit of a Kerr-NUT-AdS black hole, the space of conformal Killing-Yano two-forms does not enhance and remains of dimension two. The same holds for an analogous polar limit in the case of extremal NUT charge. We also derive the conformal Killing-Yano $p$-form equation for any background in arbitrary dimension in the form of parallel transport.
36 pages, 12 pdf figures, v2: minor changes