Browsing Astronomy by Title
Now showing items 47-63 of 63
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The Astrophysics of Active Galactic Nuclei Variability in Large Scale Spectroscopic Surveys
More than 50 years after the initial discovery of the extragalactic nature of quasi-stellar objects (quasars) by Schmidt (1963), studies of luminous active galactic nuclei (AGN) have revolutionized our understanding of ... -
The Binary Fraction of Red Supergiants
The binary fraction of massive main sequence OB stars is thought to be as high as 70%. However, until recently, only around a dozen binary red supergiants (RSGs) had been identified, despite the fact that these stars are ... -
The Characterization and Discovery of Solar System Small Bodies in Modern Astronomical Surveys
Starting in 2024, the Vera C. Rubin Observatory will conduct a comprehensive survey of the night sky named the Legacy Survey of Space and Time (LSST). LSST will observe the Southern sky every three nights continuously for ... -
The Detection and Characterization of Terrestrial Exoplanets and Exoplanetary Satellites Via Their Transits
In recent decades the observation of planetary transits has emerged as the most successful method of exoplanet detection and characterization. Transits give us access to regions of parameter space that are inaccessible to ... -
The Detection, Characterization, and Retrieval of Terrestrial Exoplanet Atmospheres
With the upcoming launch of the James Webb Space Telescope (JWST), the first light of thirty-meter class ground based telescopes in the 2020s, and plans in the works for a next-generation space-based telescope designed ... -
The Effects of Stellar Magnetic Activity and Variability on Observations of Exoplanets
The search for life in the Universe outside of the Solar System focuses on the study of potentially habitable exoplanets. Exoplanets have been discovered principally via the transit method, which reveals planetary radii ... -
The High-Redshift Quasar Luminosity Function from Multi-Epoch Imaging Surveys
Upcoming time-domain imaging surveys such as the LSST will detect over a million high-redshift z > 4 quasars, making complete spectroscopic followup unfeasible. Statistical estimates such as luminosity functions and ... -
The Little Galaxies That Could Reionize the Universe
The sources that reionized the universe are still unknown, but likely candidates are faint but numerous galaxies. In this paper we present results from running a high resolution, uniform volume simulation, the Vulcan , to ... -
The Lyman Alpha Forest One Dimensional Power Spectrum from the Baryon Oscillation Spectroscopic Survey
We measure the one dimensional power spectrum of the transmitted ux in the Ly forest using 16,331 quasar spectra from the twelfth Data Release (DR12) of the Baryon Oscillation Spectroscopic Survey (BOSS). An analysis of ... -
The Nature and Characterization of M Dwarf Terrestrial Planetary Atmospheres: A Theoretical Case Study of the TRAPPIST-1 Planetary System
In the next few years, the launch of the James Webb Space Telescope (JWST), along with the construction of new ground-based observatories, will provide the opportunity to attempt atmospheric characterization of terrestrial ... -
The Physical Connection between Cosmic Gas Flows, Supermassive Black Holes Growth, and Galaxy Evolution
The circumgalactic medium (CGM) represents a key interface in the processes of galactic evolution. Here, the gas which enters galaxies through mergers and filaments and the gas expelled from a disk through stellar and black ... -
Three Investigations of Low Mass Stars in the Milky Way Using New Technology Surveys
At least 80% of stars in the Milky Way have masses less than or equal to the Sun. These long lived stars are the most likely hosts of planets where complex life can develop. Although relatively stable on the timescale of ... -
Time-Resolved Properties and Global Trends in dMe Flares from Simultaneous Photometry and Spectra
(2013-02-25)We present a homogeneous survey of near-ultraviolet (NUV) /optical line and continuum emission during twenty M dwarf flares with simultaneous, high cadence photometry and spectra. These data were obtained to study the ... -
Using Metals and Stars to Constrain Galaxies' Past Gaseous Inflows and Outflows
As galaxies evolve, they must enrich and exchange gas with the surrounding medium, but the timing of these processes and how much gas is involved remain poorly constrained by observations. In this thesis, I use observations ... -
What's happening around Herbig Ae stars?: investigating circumstellar activity in young intermediate mass stars with optical and near-infrared spectroscopy
(2001)We have investigated the optical and near-infrared spectral behavior of the intermediate mass, pre-main sequence Herbig Ae stars, with particular emphasis on variability and evolution. The evolutionary state of Herbig Ae ... -
X-ray Binary Evolution and the Connection to Star Formation in Nearby Galaxies with the Chandra Local Volume Survey
(2014-02-24)X-ray binaries, especially those with a massive stellar companion, provide a unique probe through which one can study the end-points of high-mass stellar evolution while simultaneously tracing recent star formation. In ... -
X-ray Insights into Massive Star Evolution: the X-ray Source Population of M33 as seen by XMM-Newton, Chandra, and the Hubble Space Telescope
Massive stars are key drivers in the cycle of star formation and overall galactic chemical evolution, but many aspects of the evolution of high-mass stars, in particular the end stages of their lifetimes, are difficult to ...