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...
Gamma ray bursts (GRBs) are short, intense pulses of gamma rays that emit radiation in a narrow beam. Unless the beam is oriented towards the observer, it is often difficult to resolve the bursts against the diffuse gamma ray background (DGRB). The DGRB is a measured source of gamma rays...
The binding energies of n < 100 carbon clusters are calculated using the ab initio density functional theory code
Quantum Espresso. Carbon cluster geometries are determined using several levels of classical techniques and further
refined using density functional theory. The resulting energies are used to compute the work of cluster...
During AY 2009/10 OSU Libraries’ Research and Innovative Services Department (RIS) conducted a pilot project on “environmental scanning.” One of our goals for the year is to develop a process to investigate emerging trends based on a topic and disseminate our findings. Initially we each scanned a segment of the...
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American Astrophysical Society’s
Astronomical Journal and the product is named AJ Compilations. The
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...
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...
Gravitational waves (GWs) are disturbances in spacetime that can be caused by events such as black hole mergers and supernovae, as well as continuous sources such as binary star systems. GWs offer a new avenue of astrophysical research and can reveal information about the early universe. GW detection can be...
We report zero kinetic energy (ZEKE) photoelectron spectroscopy of benzo[a]pyrene (BaP) via resonantly enhanced multiphoton ionization (REMPI). Our analysis concentrates on the vibrational modes of the first excited state (S₁) and those of the ground cationic state (D₀). Similar to pyrene, another peri-condensed polycyclic aromatic hydrocarbon we have investigated, the...
The discovery of GW170817 provided the first empirical evidence that merging binary neutron star systems are both progenitors of short gamma-ray bursts, as well as the primary sites of the nucleosynthetic rapid-neutron capture process. Initially detected as gravitational wave (GW) and gamma-ray burst (GRB) triggers, GW170817 was well-localized and follow-up...