Thesis (M.S.)--Montana State University--Bozeman, 2007. / Typescript. Chairperson, Graduate Committee: Robert L. Mokwa. Includes bibliographical references (leaves 89-91).

Thesis (Ph. D.)--University of Oregon, 2006. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 208-221). Also available for download via the World Wide Web; free to University of Oregon users.

Thesis (Ph. D.)--University of Canterbury, 2008. / Typescript (photocopy). "August 2008." Includes bibliographical references (p. [201]-209). Also available via the World Wide Web.

We examine the fraction of massive (M-* > 10(10)M(circle dot)) compact star-forming galaxies (cSFGs) that host an active galactic nucleus (AGN) at z similar to 2. These cSFGs are likely the direct progenitors of the compact quiescent galaxies observed at this epoch, which are the first population of passive galaxies to appear in large numbers in the early Universe. We identify cSFGs that host an AGN using a combination of Hubble WFC3 imaging and Chandra X-ray observations in four fields: the Chandra Deep Fields, the Extended Groth Strip, and the UKIDSS Ultra Deep Survey field. We find that 39.2(-3.6)(+3.9)% (65/166) of cSFGs at 1.4 < z < 3.0 host an X-ray detected AGN. This fraction is 3.2 times higher than the incidence of AGN in extended star-forming galaxies with similar masses at these redshifts. This difference is significant at the 6.2 sigma level. Our results are consistent with models in which cSFGs are formed through a dissipative contraction that triggers a compact starburst and concurrent growth of the central black hole. We also discuss our findings in the context of cosmological galaxy evolution simulations that require feedback energy to rapidly quench cSFGs. We show that the AGN fraction peaks precisely where energy injection is needed to reproduce the decline in the number density of cSFGs with redshift. Our results suggest that the first abundant population of massive quenched galaxies emerged directly following a phase of elevated supermassive black hole growth and further hints at a possible connection between AGN and the rapid quenching of star formation in these galaxies.

No description available.

This thesis consists of the structures of two compounds as determined by single crystal x-ray diffraction. The first structure is that of a phosphazene - iodine complex: hexamethylcyclotriphosphazene - iodine (1:1 adduct) and the second structure is the redetermination of sodium formate. Crystals of hexamethylcyclotriphosphazene - iodine (1:1 adduct) are triclinic, a = 10.707(13), b = 8.873 (5), c = 8.871(6)Å, α = 96. 65 (6), β = 103.91 (12), ɤ = 97.81(12)°, Z = 2, space-group PI. The structure was determined with Mo-K« diffractometer data by Patterson and Fourier synthesis, and was refined by full-matrix least-squares calculations to R = 0.053 for 1934 observed reflexions. The iodine molecule is weakly bonded to a nitrogen atom on the phosphazene ring, N - I = 2.417(7), I - I = 2. 823 (1) Å, N - I - I = 177.8(2)°. The six-membered phosphazene ring is slightly, but significantly, ncn-planar, the conformation being that of a chair. The molecule has pseudo-m symmetry. Two distinct P-N bonds are present; the longer ones, mean P - N = 1.64 Å, involve the nitrogen that is weakly bonded to the iodine molecule, while the other four P-N bonds are equivalent, mean P - N = 1.598 Å. All the P - C bonds are equivalent, mean P - C = 1.789 Å. The mean endocyclic N - P - N and P - N - P angles are 114.7 and 124.0° respectively, while the mean exocyclic C - P - C angle is 104°. Crystals of sodium formate are mcnoclinic, a = 6.2590 (6), b = 6.7573 (16) , c = 6.716 (5) Å, β = 116.140(6)°, Z = 4, space-grcup C2/c. The structure was determined by direct methods, and was refined by electron density and full-matrix least-squares procedures to E = 0.022 for 250 reflexions. Sodium formate is planar and has C2V symmetry. Partial charges were refined on the formate ion. The partial charges found on each atom are as follows: 0 -0.23(1)e, C +0.16(3)e, H -0.49(10)e, and Sa +0.79(14)e. The sodium ion has six oxygen neighbours at an average distance of 2.45 Å and there are weak Na. ..0 interactions. There is a C - H...Na hydrogen bond which forms continuous rows of sodium formate ions. The C - 0 bond distance is 1.246(1)Å and the 0 - C - 0 angle is 126.3(2)°. / Science, Faculty of / Chemistry, Department of / Graduate

No description available.

The 60 kev x-rays from Americium-241 (241Am) have been used in an x-ray attenuation experiment to measure the thickness and attenuation coefficient of an aluminum alloy. Using traditional measurement tools such as a micrometer, to determine the thickness and uniformity of soft metal targets and curved aluminum target cell windows is challenging. Furthermore, the determination of window thickness is important to Jefferson Lab experiments, in particular the Qweak experiment. In this thesis, the thickness of Aluminum foil AL7057 is determined with high accuracy using x-ray attenuation. Using the x-ray attenuation technique has the advantage of nondestructive measurement.

No description available.

No description available.