Search

We have succeded in creating Bose-Einstein condensates with 2 million sodium atoms in a '4D' magnetic trap. We show the dynamic formation of a condensate as evaporative cooling proceeds. We also present a series of trap-release pictures clearly showing the distinctly different modes of expansion of condensate and thermal cloud. We further give two examples of wave guides for atomic de Broglie matter waves. One structure, the Kapitza wave guide, uses the interaction between an electrically polarizable atom and a charged wire. For stably bound orbits, a dynamical stabilization with time dependent potentials is necessary. This system, which can be tuned freely between classical and quantum regimes, shows chaotic behavior in the classical limit. The static counterpart of this wave guide leads to the introduction of the 'angular momentum quantum ladder' . The second wave guide structure is based upon the interaction between a current carrying wire and the magnetic dipole moment of an atom. A hydrogenic spectrum of bound states is derived through the concept of supersymmetry., Comment: 11 pages, 5 figures Accepted for publication in Photonic, Electronic & Atomic Collisions (Proceedings of the XX.ICPEAC, Vienna, Austria, July 1997, eds. F. Aumayr & H.P. Winter), World Scientific, 1998, in press

We present quantitative measurements of the spatial density profile of Bose-Einstein condensates of sodium atoms confined in a new '4D' magnetic bottle. The condensates are imaged in transmission with near resonant laser light. We demonstrate that the Thomas-Fermi surface of a condensate can be determined to better than 1%. More generally, we obtain excellent agreement with mean-field theory. We conclude that precision measurements of atomic scattering lengths and interactions between phase separated cold atoms in a harmonic trap can be measured with high precision using this method., Comment: 15 pages, 3 figures. Submitted 10/30/97, accepted for publication in Phys. Rev. A Rapid Comm

This study explores current trends and practices in functional integration based on site visits to six Association of Research Libraries (ARL) member libraries selected on the basis of their responses to a Fall 1984 ARL questionnaire. The responses indicated that, for all six libraries, some integration of functions existed, staff reorganization was underway or complete, cataloging was taking place in public areas, and professional librarians were participating in both public and technical services functions. The current situation of the six libraries and their decisions to reorganize are summarized, and the following developments and issues are considered: (1) collection management and service to users; (2) impact of automation; (3) organizational climate; (4) flexible use of staff; (5) staff morale; (6) reporting relationships; and (7) recruitment and training. Increased information delivery and an expansion outward in client-centered groupings are identified as possible future trends for public service areas, along with the continuing compression of massive technical services departments, and it is concluded that leadership and staff participation, as well as a clear sense of where the institution is going, are vital ingredients in successful organizational change. Notes and a 61-item selected bibliography are provided, and a listing of the issues addressed is appended. (KM)