Context. Measurement of the Galactic neutral atomic hydrogen (H I) column density, NH I, and brightness temperatures, T-B, is of high scientific value for a broad range of astrophysical disciplines. In the past two decades, one of the most-used legacy H I datasets has been the Leiden/Argentine/Bonn Survey (LAB). Aims. We release the H I 4 pi survey (HI4PI), an all-sky database of Galactic H I, which supersedes the LAB survey. Methods. The HI4PI survey is based on data from the recently completed first coverage of the Effelsberg-Bonn H I Survey (EBHIS) and from the third revision of the Galactic All-Sky Survey (GASS). EBHIS and GASS share similar angular resolution and match well in sensitivity. Combined, they are ideally suited to be a successor to LAB. Results. The new HI4PI survey outperforms the LAB in angular resolution (theta(FWHM) = 16'.2) and sensitivity (sigma(rms) = 43 mK). Moreover, it has full spatial sampling and thus overcomes a major drawback of LAB, which severely undersamples the sky. We publish all-sky column density maps of the neutral atomic hydrogen in the Milky Way, along with full spectroscopic data, in several map projections including HEALPix.

Thesis (Ph. D.)--Washington State University, December 2007. / Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.

Not available / text

The dynamics of non-interacting, ultracold alkali atoms in the presence of counter-propagating lasers (optical lattice systems) is considered theoretically. The center of mass motion of an atom is such a system can be described by an effective Hamiltonian of a relatively simple form. Modulation of the laser fields implies a parametric variation of the effective Hamiltonian's eigenvalue spectrum, under which avoided crossings may occur. We investigate two dynamical processes arising from these near-degeneracies, which can be manipulated to coherently control atomic motion. First, we demonstrate the mechanism for the chaos-assisted, or multiple-state, tunneling observed in recent optical lattice experiments. Second, we propose a new method for the coherent acceleration of lattice atoms using the techniques of stimulated Raman adiabatic passage (STIRAP). In each case we use perturbation analysis to show the existence of a small, few level, subsystem of the full effective Schrödinger equation that determines the dynamics. / text

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

No description available.

No description available.

Preparatory steps for the experimental investigation of the highly forbidden 5s - 6s transition in rubidium using an atom trap and laser cooling are reported. A magneto-optical trap (MOT) has been assembled including saturation spectroscopy and a dichroic vapor laser lock. A frequency-doubled diode laser system has been installed to perform the spectroscopy of the forbidden transition with cold Rb atoms in the trap. The properties of the ns - n's transition in the presence of an external electric fi#12;eld have been investigated theoretically. A fi#12;rst measurement will be exploring the Stark-induced transition amplitude and the very faint magnetic dipole amplitude. The rubidium experiment is a precursor study for a long-term project at TRIUMF, Canada's National Laboratory for nuclear and particle physics, to measure atomic parity violation in the equivalent 7s - 8s transition in francium, the heaviest alkali atom which has no stable isotopes.

Preparatory steps for the experimental investigation of the highly forbidden 5s - 6s transition in rubidium using an atom trap and laser cooling are reported. A magneto-optical trap (MOT) has been assembled including saturation spectroscopy and a dichroic vapor laser lock. A frequency-doubled diode laser system has been installed to perform the spectroscopy of the forbidden transition with cold Rb atoms in the trap. The properties of the ns - n's transition in the presence of an external electric fi#12;eld have been investigated theoretically. A fi#12;rst measurement will be exploring the Stark-induced transition amplitude and the very faint magnetic dipole amplitude. The rubidium experiment is a precursor study for a long-term project at TRIUMF, Canada's National Laboratory for nuclear and particle physics, to measure atomic parity violation in the equivalent 7s - 8s transition in francium, the heaviest alkali atom which has no stable isotopes.