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Exploring Habitability Markers, Biosignatures, and Their False Positives Using Spectral Models of Terrestrial Exoplanets
In the coming years and decades, we will obtain our first opportunity to spectrally characterize potentially habitable worlds outside our solar system. These planets will be at the right distance from their host star and possess the correct range of atmospheric compositions to have surfaces conducive to maintaining liquid ...
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 clustering measurements will require purely photometric methods for classifying quasars, estimating redshifts ...
Resolved Stars' Insights into Galaxy Physics
The history of a galaxy is encoded in its individual stars, and resolved stellar populations in nearby galaxies provide a wealth of information about star formation history (SFH), its relation to the interstellar medium, and galactic dynamics/structures. Using the power of resolved stars, imaged in multiple wavelengths by the ...
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 predict the number densities of undetectable, faint galaxies and their escape fractions of ionizing ...
Pulling Back the Veil: The Characterization and Habitability of Enshrouded Worlds
This dissertation explores global atmospheric haze and cloud layers and shows that they are not impenetrable barriers to information about the lower atmosphere and surface environment of planets. Uncovering techniques to probe beneath these aerosol decks can reveal a wealth of knowledge about planetary environments that would ...
A sub-kiloparsec scale view of star formation in M31
This dissertation examines the properties of star formation in the nearest large Milky Way- like galaxy, the Andromeda Galaxy (M31). Using resolved star data from the Hubble Space Telescope obtained as part of the Panchromatic Hubble Andromeda Treasury (PHAT), I model the optical color-magnitude diagrams (CMDs) of > 9000 ...
Drivers of Turbulence in the Neutral Interstellar Medium of Dwarf Galaxies
(2013-07-23)
The cause of HI velocity dispersions in the interstellar medium (ISM) of galaxies is often attributed to star formation, but recent evidence has shown these two quantities are not connected in regions of low star formation. This lack of connection is most apparent in dwarf galaxies and the outer disks of spiral galaxies. ...
The Milky Way in SDSS and in N-body Models
(2013-11-14)
In this thesis, I present a comparison between recent Sloan Digital Sky Survey (SDSS) Galactic studies and N-body simulations to aid in the interpretation of observed structural features. I investigate the origin of the Galactic thin/thick disk system and the contents of the Galactic halo by drawing comparisons to two high ...
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 this caliber requires a thorough understanding of the data, and the majority of this thesis is aimed at ...
Modeling the Extragalactic Epoch of Reionization Foreground
The Epoch of Reionization represents a largely unexplored yet fundamental chapter of the early universe. During this period, spanning several hundred million years, the first stars and galaxies formed and the Hydrogen-dominated intergalactic medium transitioned from a predominantly neutral to ionized state. Modern efforts to ...