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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
341

A History of the Latter-Day Settlement of Star Valley, Wyoming

Hall, Ray McCord 01 January 1962 (has links) (PDF)
The Latter-day Saints were good colonizers, possibly because they were repeatedly forced by persecution to seek new homes in the wilderness. Having established themselves in Salt Lake Valley (1847), they began almost immediately to expand their domain. Their Prophet, Brigham Young, sent groups of Mormons to colonize the surrounding valleys, and within a few years there were many Mormon settlements beyond the bounds of Salt Lake Valley. Bear Lake Valley in southeastern Idaho and northern Utah was one of these early settlements.Star Valley--thus named by Moses Thatcher, an Apostle in the Church who thought it was a "star among valleys"--lay in the territory of Wyoming some sixty miles beyond the Bear Lake Valley. Because of its extreme isolation it was slow to attract permanent settlers, although it was used for sumner pasture by the Bear Lake people and it was traversed by many Oregon immigrants who followed the Lander Cut-off.
342

Molecular Clouds Across the Local Star-forming Galaxy Population

Sun, Jiayi January 2021 (has links)
No description available.
343

A Near-Infrared View of Structure and Star Formation in Galaxies

Kessler, Sarah Jayne January 2021 (has links)
No description available.
344

Processing of Simulated and Experimental Images of Closely Spaced Binary Stars Using Speckle Interferometry

Smidth, Niels 01 June 2016 (has links) (PDF)
Theory and methods of processing speckle interferometry data from close visual binary stars are presented and implemented. The effects of the optical systems used for observing close visual binary stars are explained and simulated from both the geometrical and physical optical viewpoints. The atmospheric phase distortion and shot noise responsible for the observed speckle patterns are simulated. The deconvolution technique originally presented by Labeyrie is implemented to extract astrometric data from close visual binary stars. This method is applied to both simulated and experimental data from Kitt Peak National Observatory as validation. Parts of the deconvolution process are optimized to allow for near real time calculations in an automated observatory.
345

Infrared and X-ray Studies of the Galactic Center

Dong, Hui 01 September 2011 (has links)
The purpose of this dissertation is to locate evolved massive stars within the central 50 pc of the Galactic Center. These stars are considered to be the descendants of O stars and should be less than 10 Myr old. They trace young star clusters within the Galactic Center. Through these stars and young star clusters, we hope to understand the star formation mode and history within the Galactic Center, as well as the properties of evolved massive stars in the high metallicity environment. We first study the Chandra X-ray deep survey of the Arches and Quintuplet clusters, two of the three young massive star clusters within the Galactic Center. The diffuse X-ray emission is used to constrain their initial mass function and we find a deficiency of low-mass stars, which could be explained by an ongoing collision between the clusters and the adjacent molecular clouds. We then perform a systematic search of young massive stars on a large scale within the Galactic Center through our new HST/NICMOS Paschen-alpha survey. We produce mosaic maps of the Paschen-alpha line and continuum emission, giving an unprecedentedly high resolution and high sensitivity panoramic view of stars and photo-ionized gas in the nuclear environment of the Galaxy. Many new HII regions and extended emission regions have been found. Combined with the archived HST snapshot observations and spectroscopic observations, we construct a sample of 180 potentially evolved massive stars. A multi-wavelength study of these stars is conducted. We find that young massive stars have continued to form within the Galactic Center during the last 10 Myr and some of the evolved massive stars may represent star formation in small groups or even in isolation, compared to the three massive star clusters within the Galactic Center
346

The Gas Kinematics of High Mass Star Forming Regions

Klaassen, Pamela D. January 2008 (has links)
The mechanism by which massive stars form is not nearly as well understood as it is for lower mass stars. For instance, at the onset of massive star formation, it is still not clear whether the mass for a given massive star comes from the turbulent collapse of a dense core (i.e McKee & Tan, 2003) or whether the star continues to accrete material from the cores environment as it grows (i.e. Bonnell et al., 1998). From this point, it is suggested that the cold, massive core (an Infrared Dar Cloud) begins to heat up and form a Hot Core. Later in its protostellar evolution, an HII region forms from the ionizing radiation being produced by the massive star. How, or even whether, accretion onto the massive protostar can continue in the presence of the large outward thermal and radiation pressures from the star is also quite uncertain. Can the star continue to accrete ionized gas (i.e. Keto & Wood, 2006)? Are the accretion rates high enough early on to account for the final observed masses (i.e. Klaassen et al., 2006)? Or, is there some way of minimizing the radiation pressure affecting the infalling gas (i.e. McKee & Ostriker, 2007, and references therein). Here, we present observations which suggest that there is a statistically significant, although short, period in which rotation and infall of molecular gas (which powers a bipolar outflow) continue after the formation of an HII region. This continued infall of material is seen on both large and small scales, and appears to be continuing to produce outflows in many of the sources observed in this study. That it is not seen in all sources suggests that this stage is short lived. / Thesis / Doctor of Philosophy (PhD)
347

Satellite Quenching and Morphological Transformation of Galaxies in Groups and Clusters / Galaxy Evolution in Groups and Clusters

Oxland, Megan January 2024 (has links)
Galaxy properties are known to correlate with their environment, suggesting that environment plays a significant role in galaxy evolution. In particular, blue star forming spiral galaxies are preferentially found in low density regions while red, passive elliptical galaxies are found in the densest clusters. This suggests galaxies falling into groups and clusters experience a decrease in their star formation rate (SFR) and a morphological transformation from spiral to elliptical, but the timescales associated with these changes are not well constrained. This thesis explores the impact of environment on galaxy SFRs and morphologies for a large sample of galaxies from the Sloan Digital Sky Survey. We separate galaxies into two environments (groups and clusters) and use location in projected phase space as an estimate for how long a galaxy has been a part of its current environment. We calculate the timescales associated with the changes in galaxy SFRs and morphologies, and determine SFRs change more quickly than morphology. By comparing to a sample of field galaxies, we find evidence that prior group environments impact current galaxy properties via pre-processing. / Thesis / Master of Science (MSc)
348

The Disney College Experience: A Full Recollection of Moments and Memories of the Disney College Program Internship

Jumonville, Lauren 01 December 2023 (has links) (PDF)
I decided to do the Disney College Program as my honors thesis because Disney is something I am very passionate about. I worked for the Disney Company before and knew that I wanted to continue my experience with them. I went into the program hoping to discover what the college program could do to prepare me (or any prospective programmer) for the profession and for a life in performance. In January of 2023, I made my way to Orlando, Florida, to start my next journey with the Walt Disney World Company. I went through four different orientation processes, as well as a week of training and an assessment period. For five months I worked for the company in a performance-based position, with hopes of discovering if there could be more opportunity to advance in performance. I discovered that by simply doing the job I was assigned well, my name was already beginning to circulate amongst Disney recruitment and leadership. This is the account of my semester in Walt Disney World. This thesis will cover everything from the application process to testimonials from other cast members. My hope is that my thesis can be a starting point for prospective applicants to this program. It is my hope that this will help prepare applicants for what is to come from the program, and the endless amount of performance opportunities and growth that stem from this internship.
349

Globular Cluster System Properties by Host Galaxy Environment

Hartman, Kate January 2022 (has links)
I present Hubble Space Telescope photometry in optical (F475X, 475 nm) and near-infrared (F110W, 1.1 μm) bands of the globular cluster (GC) system of the inner haloes of a sample of 15 brightest cluster galaxies (BCGs). I also present a quantitative model of the relation between (F475X - F110W) colour and cluster metallicity, using simulated GCs. The sample comprises massive elliptical galaxies in a range of environments, from sparsely populated groups to dense clusters. Because the material available for large galaxies to accrete varies with environment and GC systems of such galaxies are built up through accretion, I expect the metallicity distribution of the GC systems in my sample to vary with galaxy environment. GC systems in massive elliptical galaxies tend to follow a bimodal colour distribution, with two subpopulations of blue (metal-poor) and red (metal-rich) clusters. The photometry is used to create a completeness-corrected metallicity histogram for each galaxy in my sample, and to fit a double Gaussian curve to each histogram in order to model the two subpopulations. Finally, the properties of the GC metallicity distribution are correlated against each BCG environment. I found that almost no GCS properties and host galaxy environmental properties are correlated, with the exception of weak but consistent correlations between number of GCs and nth-nearest neighbour surface density and between blue fraction and nth-nearest neighbour surface density. / Thesis / Master of Science (MSc)
350

Disney’s Girl Next Door: Exploring the Star Image of Annette Funicello

Folkins, Claire Victoria 28 March 2006 (has links)
No description available.

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