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  • The Formation of Astrophysical Dust

    Creator:
    Mauney, Christopher M.
    Abstract:
    The formation of carbonaceous and silicate precursor molecules to astrophysical dust grains is investigated. Using density functional theory (DFT) in combination with global optimization techniques, the ground-state binding energies of dust precursors are determined. These results are employed in atomistic nucleation theory (ANT) to predict the critical size and nucleation...
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    Dissertation
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    of Astrophysical Dust Abstract approved: Davide Lazzati The formation of carbonaceous and silicate

  • Zero kinetic energy photoelectron spectroscopy of polycyclic aromatic hydrocarbons

    Creator:
    Zhang, Jie
    Abstract:
    In this dissertation, I present electronic spectra of a few polycyclic aromatic hydrocarbons (PAHs): tetracene, pentacene, pyrene, benzo[g,h,i]perylene and benzo[a]pyrene using resonantly enhanced multiphoton ionization (REMPI) and zero kinetic energy (ZEKE) photoelectron spectroscopy. The work of tetracene and pentacene also combine a laser desorption source with a ZEKE spectrometer, demonstrating...
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    Dissertation
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    study is to offer a database for astrophysical modeling, in terms of both direct line identification

  • Zero Kinetic Energy Photoelectron Spectroscopy of Polycyclic Aromatic Hydrocarbons

    Creator:
    Harthcock, Colin
    Abstract:
    In this dissertation, I describe spectroscopic studies of jet-cooled polycyclic aromatic hydrocarbons (PAH) and one nitrogen substituted PAH (PANH) using pulsed field zero kinetic energy (ZEKE) photoelectron spectroscopy and resonantly enhanced multiphoton ionization (REMPI) spectroscopy. Recently, there has been a demand for far-infrared (FIR) spectral information of astrophysically relevant molecules...
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    Dissertation
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    astrophysical environment, we have initiated a systematic study of polycyclic aromatic hydrocarbons

  • Monte Carlo Radiation Transfer Simulations of Gamma Ray Burst Prompt Emission

    Creator:
    Parsotan, Tyler M.
    Abstract:
    Gamma Ray Bursts (GRBs) are the most energetic explosions in the Universe, producing up to $\sim10^{53}$ ergs of energy in the first few seconds of their emission -- the so-called prompt phase that is dominated by high energy X-ray and $\gamma$-ray photons. The very large luminosities released in these events...
    Resource Type:
    Dissertation
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    make measurements of nearly every astrophysical system, each theoretical model that attempts to

  • Education of American research astronomers, 1876-1941

    Creator:
    Hall, Robert Dale, 1947-
    Abstract:
    The education (particularly graduate education) of Americans who were active in astronomical research between 1876 and 1941 is assessed for its effectiveness in preparing the astronomers for careers in research. This period contains three dynamic changes: the growth of American astronomy in becoming the world's leading community of astronomers, the...
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    Dissertation
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    ................................................................................................ 645 2 1 .5 Numbers of Doctorates in Different Astrophysical Fields

  • Searches for a General Transverse Polarization Mode of Gravity using Pulsar Timing Arrays

    Creator:
    Laal, Nima
    Abstract:
    Given the recent advancements in the field of pulsar timing pertaining to the detection of a stochastic gravitational wave background (GWB), it is now the perfect time to perform tests of gravity via exploration of the correlation signature between the timing data of pairs of pulsars induced by the polarization...
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    Dissertation
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    arrays by studying the polarization content of an elusive astrophysical phenomenon named the

  • The South Atlantic Ocean response to local and remote forcings

    Creator:
    Fetter Filho, Antonio F. H.
    Abstract:
    The local and remote sources of variability of the South Atlantic Ocean are investigated using a set of numerical experiments and satellite data. A global, eddy-permitting, numerical simulation is analyzed to investigate the dynamical links between the Antarctic Circumpolar Current (ACC) and the Malvinas Current (MC). The model results indicate...
    Resource Type:
    Dissertation
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    statistical analysis and prediction of geophysical fluid systems, Geophysical and Astrophysical Fluid

  • Mars and Popular Astronomy, 1890-1910

    Creator:
    Simpson, Emily M.
    Abstract:
    Beginning in the late-nineteenth century, several dialogues emerged concerning life on Mars. Some supported the notion of an inhabited Mars, citing recent observations of the planet, while others, pointing to a lack of concrete evidence, denied the validity of such a bold hypothesis. The dialogues within and between different...
    Resource Type:
    Dissertation

  • The rotating sector disk as used in an optical pyrometer

    Creator:
    Varner, William Roy, 1889-1967
    Resource Type:
    Dissertation

  • Radiative Acceleration and Emission from Relativistic Outflows

    Creator:
    Chhotray, Atul
    Abstract:
    Outflowing streams of matter or jets are a common phenomenon in the observeduniverse. The most extreme and powerful jets are relativistic, i.e., they travel at speedscomparable to the of speed light. Gamma Ray-Bursts (GRBs) and Active Galactic Nuclei(AGNs) are two sources of these relativistic jets. In this work I will...
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    Dissertation
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    of matter from astrophysical objects is a commonly occurring phenomenon in astrophysics (Livio 1999