22 research outputs found
-particle condensate states in O
The existence of a rotational band with the +C()
cluster structure, in which three particles in C() are
locally condensed, is demonstrated near the four- threshold of O
in agreement with experiment. This is achieved by studying structure and
scattering for the +C() system in a unified way. A
drastic reduction (quenching) of the moment of the inertia of the state
at 15.1 MeV just above the four- threshold in O suggests that it
could be a candidate for the superfluid state in -particle
condensation.Comment: 5 pages, 3 figure
DIRECT OBSERVATION OF RYDBERG{--}RYDBERG TRANSITIONS IN CALCIUM ATOMS
Author Institution: Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139Chirped Pulse millimeter-Wave (CPmmW) spectroscopy, an extension of Brooks Pate's Chirped Pulse Fourier Transform Microwave (CP-FTMW) technique, has been adapted to observe electronic transitions between Rydberg states. The feasibility of this method has been demonstrated on calcium atoms of effective principal quantum number of 40 and at frequencies of 70{--}84 GHz. Whereas Rydberg states are generally detected by ionization, we directly observe the free induction decay that they emit after polarization by the chirped pulse. Spectra with a bandwidth of 10 GHz and resolution of 1 MHz or better may be acquired in several shots, which could enable high-resolution ``pure electronic'' spectroscopy of molecules in core-nonpenetrating Rydberg states. The available millimeter-wave power is not a limitation in this experiment because the transition dipole moments are large (5,000 Debye). Furthermore, the ability to quickly and arbitrarily polarize the sample opens avenues for optical plus millimeter-wave coherent experiments. Schemes to extend this technique to molecules are under development