Mapping trilobite state signatures in atomic hydrogen
  A few-body approach relying on static line broadening theory is developed to treat the spectroscopy of a single Rydberg excitation to a trilobite-like state immersed in a high density ultracold medium. The present theoretical framework implements the compact treatment of polyatomic Rydberg molecules by Eiles et al. [arXiv:1601.06881], allowing for an accurate treatment of a large number of perturbers within the Rydberg orbit. This system exhibits two unique spectral signatures: its lineshape depends on the Rydberg quantum number $n$ but, strikingly, is independent of the density of the medium, and it is characterized by sharply peaked features reflecting the oscillatory structure of the potential energy landscape. 
Jes\'us P\'erez-R\'ios, Matthew T Eiles, Chris H Greene
physics.atom-ph