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The AzTEC Millimeter-wave Camera: Design, Integration, Performance, and the Characterization of the (sub-)millimeter Galaxy PopulationAustermann, Jason Edward 01 May 2009 (has links)
One of the primary drivers in the development of large format millimeter detector arrays is the study of sub-millimeter galaxies (SMGs) - a population of very luminous high-redshift dust-obscured starbursts that are widely believed to be the dominant contributor to the Far-Infrared Background (FIB). The characterization of such a population requires the ability to map large patches of the (sub-)millimeter sky to high sensitivity within a feasible amount of time. I present this dissertation on the design, integration, and characterization of the 144-pixel AzTEC millimeter-wave camera and its application to the study of the sub-millimeter galaxy population. In particular, I present an unprecedented characterization of the "blank-field" (fields with no known mass bias) SMG number counts by mapping over 0.5 deg 2 to 1.1mm depths of ∼1mJy - a previously unattained depth on these scales. This survey provides the tightest SMG number counts available, particularly for the brightest and rarest SMGs that require large survey areas for a significant number of detections. These counts are compared to the predictions of various models of the evolving mm/sub-mm source population, providing important constraints for the ongoing refinement of semi-analytic and hydrodynamical models of galaxy formation. I also present the results of an AzTEC 0.15 deg 2 survey of the COSMOS field, which uncovers a significant over-density of bright SMGs that are spatially correlated to foreground mass structures, presumably as a result of gravitational lensing. Finally, I compare the results of the available SMG surveys completed to date and explore the effects of cosmic variance on the interpretation of individual surveys.
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Constraining the Temperature Evolution of the Cosmic Microwave Background Using the Sunyaev Zel’dovich Effect with SPT-3GKorman, Milo 27 January 2023 (has links)
No description available.
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A Theoretical Study of Elementary Processes in Interstellar PlasmaForer, Joshua 01 January 2023 (has links) (PDF)
Interstellar plasma — interstellar clouds in particular — play an important role in determining the structure and evolution of galaxies. Understanding the time evolution of such plasmas requires knowledge of the chemical processes that drive their dynamics. Two processes are studied in this dissertation: radiative electron attachment (REA) via dipole-bound states (DBSs) and dissociative recombination (DR). Of the several hundred molecules detected in the interstellar medium, only eight anions have been detected: CN-, C3N-, C5N-, C7N-, C4H-, C6H-, C8H-, and C10H-. Their production mechanism is not well known; REA was suggested as a possible formation pathway, but previous theoretical studies have found that REA rate coefficients were too low to explain the formation of CN-, C3N-, and C5N-. It was later suggested that including DBSs — an electron weakly bound at a large distance to the large dipole moment of a neutral molecule — could appreciably enhance the REA rate coefficients. The first portion of this study is dedicated to investigating the role of the large dipole moment of rotating C3N using an accurate \it ab initio approach with electronic and rotational resolution. DBS wavefunctions of C3N- are calculated and used to obtain REA cross sections that produce even smaller rate coefficients, suggesting that C3N- is efficiently formed by a different process. The second part of this study investigates DR in the difficult case of molecules with low-lying eletronic resonances, although these are not necessary for the approach. An approach to treat both direct and indirect mechanisms of DR in a diatomic ion with electronic, vibrational, and rotational resolution using R-matrix scattering calculations, frame transformation theory, and multichannel quantum defect theory is presented and applied to the CH+ and CF+ molecular ions at low collision energies. The calculated CH+ cross sections agree well with recent rotationally state-resolved experimental results and overall better than previous theoretical results. The calculated CF+ cross sections agree well with experimental results, although these do not have rotational resolution, and overall better than previous theoretical results at low energies. Additionally, the method can study rovibronic (de-)excitation — a process in competition with DR. These are calculated and compared to previous theoretical calculations for CH+, which which our results agree well with the exception of dipole-driven rotational excitation cross sections. This discrepancy is tentatively attibuted to negelcting the contribution of higher partial waves in the description of the incident electron, which will be incorporated in future studies.
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The Formation and Evolution of Intracluster Light: Simulations and ObservationsRudick, Craig S. January 2011 (has links)
No description available.
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Constraining Cosmology with Weak Gravitational LensingMurphy, Kellen J. January 2013 (has links)
No description available.
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The Metallicities and Kinematics of RR Lyrae Variables from ASASChen, Xiao 28 July 2015 (has links)
No description available.
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Effect of Wavelength Dependent Point Spread Function on Shear MeasurementsMunir, Riffat 22 September 2016 (has links)
No description available.
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Self-Gravitating Eccentric Disk Models for the Double Nucleus of Μ31Salow, Robert M. 30 June 2004 (has links)
No description available.
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HI in the M31/M33 EnvironmentFree, Nicole Lynn January 2010 (has links)
No description available.
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From Galaxies to the Intergalactic MediumPeeples, Molly S. 28 September 2010 (has links)
No description available.
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