We study a one dimensional gas of repulsively interacting ultracold bosons
trapped in a double-well potential as the atom-atom interactions are tuned from
zero to infinity. We concentrate on the properties of the excited states which
evolve from the so-called NOON states to the NOON Tonks-Girardeau states. The
relation between the latter and the Bose-Fermi mapping limit is explored. We
state under which conditions NOON Tonks-Girardeau states, which are not
predicted by the Bose-Fermi mapping, will appear in the spectrum.Comment: 5 pages, 5 figure