For the past several decades, mass estimates for supermassive black holes hosted by active galactic nuclei (AGN) have been made with the reverberation mapping (RM) technique. This methodology has produced consistent results and has been used to establish several relations that link the characteristics of the host galaxy to the mass of the central black hole. Despite this success, there are less than 50 AGN with black hole masses derived from RM. This low number is generally attributed to the difficulties in coordinating large blocks of telescope time for making simultaneous photometric and spectroscopic observations. Spectroscopic observations also generally require several months of nightly observations with moderate to large size telescopes as the signal-to-noise ratio is too low for smaller telescopes. We have made photometric observations of NGC 5548 in four filters (a custom-made Hα10 filter, the Strömgren y filter, the Johnson/Cousins V filter and the Johnson/Cousins R filter) in order to evaluate a photometric methodology for determining the lag time between the variations observed in the continuum and the Hα emission from the broad-line region (BLR) gas. This time delay represents the mean light travel time to the BLR and is therefore a measurement of the mean BLR radius. Multiple JAVELIN analyses of the three continuum light curves (y, V, and R), relative to the light curve from the Hα10 filter yields a value for τ = 3.3 ± 0.1 days. Adopting a value of f = 5.5, along with a single-epoch spectroscopic measurement from Park et of Δv = 4354±25 km/s, enables us to estimate a black hole mass of M_BH = 67.2±2.2x10^6 M_sun.

Dusty circumnuclear disks (CNDs) in luminous early-type galaxies (ETGs) show regular, dynamically cold molecular gas kinematics. For a growing number of these ETGs, Atacama Large Millimeter/sub-millimeter Array (ALMA) CO imaging and detailed gas-dynamical modeling have yielded moderate to high precision black hole (BH) mass (M_BH) determinations. To date, however, few studies have explored the effects of dust attenuation, or uncertainties in dust corrections, on recovered stellar luminosity models from high angular resolution optical/near-IR observations and M_BH measurements. Recent kinematic studies that modeled ALMA CO data sets have found that uncertainties in the intrinsic central stellar surface brightness slope due to dust may even dominate the BH mass error budgets. From the ALMA archive, we identified a subset of 26 ETGs with clean CO kinematics and good prospects for eventual MBH determination but that did not have sufficiently high angular resolution observations in the optical and near-IR. We have obtained new optical and near-IR Hubble Space Telescope (HST) images of this sample to supplement the archival HST data. Together, these new and archival HST data will enable the mitigation of dusty CND obscuration in the construction of dust-corrected stellar luminosity models, leading to both BH mass measurement and complete error analysis using existing ALMA CO imaging. Here, we present the sample properties, data analysis techniques, and dust-masked stellar surface brightness profiles and luminosity models using the multi-Gaussian expansion formalism. With estimated M_BH/M_⊙ ≳ 10^8 to few x10^9 , securing quality M_BH determinations for this sample of ETGs will significantly improve the high-mass end of the current BH census, facilitating new scrutiny of local BH mass-host galaxy scaling relationships.

Four experiments were conducted to investigate methods of producing transgenic bovine embryos entirely in vitro. Experiment 1 examined the effect of DNA microinjection at 11, 15 and 19 h after fertilization (haf) on survival rate and DNA detection frequency by polymerase chain reaction (PCR). There was no difference in transgene detection frequency between treatments (53% at 11; 50% at 15; 48% at 19 haf). Of all injected embryos developing to the morula or blastocyst stage after 7 d in culture, 89% tested positive for the presence of the transgene by PCR. Greater developmental efficiencies can be obtained when injection is performed early in pronuclear formation (7% (11/161) at 11; 4% (61159) at 15; 1 % (1/165) at 19 haf; p<0.05). Experiment 2 examined the effect of microinjection of DNA into the germinal vesicle (gv) of bovine oocytes on subsequent development and detection of the transgene. Injection of the transgene into the gv reduced developmental rates compared to controls (control=23% (89/384); non-injected=9% (23/250); GV injected=5% (12/259); p<O.05). Transgene detection frequency was 64% (37/58). Injection of bovine oocytes before fertilization results in viable embryos containing the transgene, although at low frequencies. Experiment 3 was designed to examine whether the frequency of microinjected DNA detection by peR In whole bovine embryos would decline over a 21 d culture period. At d 0, the transgene was detected in 100% (46/46) of embryos analyzed. At d 7, detection frequency was 84% (51/62) in viable embryos, at d 14 49% (18/37), and at d 21 38% (3/8). DNA detection frequency in microinjected bovine embryos by PCR analysis does not give a reliable indication of live transgenic birth rates until after 14 d in culture. Experiment 4 examined microinjected bovine embryos for their potential use as donor embryos in nuclear transfer, or cloning. There was no difference in development between embryos cloned from microinjected donor embryos and those from control donor embryos (injected=11 % (37/377); control=9% (7/81); p>0.05). Of the embryos developing from microinjected donors, 32% (12/37) were PCR positive. Microinjected embryos can be successfully used in a nuclear transfer program to produce more viable embryos, and the resulting embryos may be more reliably screened by PCR. The efficiency of producing viable bovine embryos positive for the injected gene may be increased by performing microinjection early in pronuclear formation, and entering the resulting embryos into a nuclear transfer program. / Ph. D.

<p> An expression is obtained for the energy per particle in neutron star matter. The energy per particle is expressed as a function of, y, the ratio of protons to the total number of nucleons in the system. Minimizing the energy with respect to y gives the optimum proton ratio at a given density. Using an effective nuclear force, the results were extrapolated to a density of p = 6pNM. The proton ratio is rather sensitive to the force used, but all forces used indicated a peak in the proton concentration at p (approximately equal to) 2pNM. The expression for the energy as a function of y was also used to interpolate the energy per particle between the nuclear matter and neutron . gas limits. The form of this interpolation is important in determining the stability of neutron-rich nuclei. </p> / Thesis / Master of Science (MSc)

Scope and Contents: A generalized pairing theory has been developed which diagonalizes matrix elements of the effective nucleon-nucleon interaction in a space of one, two and three-pair excitations from a Skyrme Hartree-Fock solution for deformed rotational nuclei. The "pairing" excitation energy for the configurations of time-reversed pairs of particles is obtained from the Hartree-Fock approximation as opposed to the conventional (BCS) residual interaction point of view. The effects of the finite-range character of the effective nucleon-nucleon interaction are studied in the single-particle structure they induce in the pairing matrix elements. Microscopic form factors for (p,t) and (t, p) reactions between states of the rotational bands built on the K^π=0^+ pairing solution band-head states are constructed in the cylindrical Harmonic-Oscillator basis in which the Hartree-Fock solution is expanded. These form factors are used in DWBA calculations for the differential cross-sections. Preliminary calculations for (p,t) and (t,p) transitions between states in 172Yb and 174Yb were performed. The calculations emphasize the effects of structure in the pairing matrix elements, and the necessity for a self-consistent calculation of the diagonal pairing matrix elements sing the Hartree-Fock equations. / Thesis / Doctor of Philosophy (PhD)

Variational calculations have been performed using various internucleon interactions in an attempt to find an interaction which would reproduce the properties of the O-p shell nuclei. These interactions were derived by fitting procedures to the S-state phase shifts and to the properties of nuclear matter. A satisfactory interaction having been obtained, studies of isobaric nuclei have been undertaken. / Thesis / Doctor of Philosophy (PhD)

The investigation of isomeric states in neutron-rich nuclei provides useful insights into the underlying nuclear configurations, and understanding their occurrence along an isotopic chain can inform about shell evolution. Recent studies on neutron-rich Si isotopes near the magic number N = 20 and approaching N = 28 have revealed the presence of low-lying states with intruder configurations, resulting from multiple-particle, multiple-hole excitations across closed shell gaps. The characterization of these states involves measuring their half-lives and transition probabilities. In this study, a new low-energy (7/2−1) isomer at 68 keV in 37Si was accessed via beta decay and characterized. To achieve this, radioactive 37Al and 38Al ions were produced through the projectile fragmentation reaction of a 48Ca beam and implanted into a CeBr3 detector, leading to the population of states in 37Si. The 68-keV isomer was directly populated in the beta-delayed one neutron emission decay of implanted 38Al ions. Ancillary detector arrays comprising HPGe and LaBr3(Ce) detectors were employed for the detection of beta-delayed gamma rays. The choice of detectors was driven by their excellent energy and timing resolutions, respectively. The beta-gamma timing method was utilized to measure the half-life of the new isomeric state in 37Si. This dissertation also discusses other timing techniques employed to search for and characterize isomeric states following beta decay of implanted ions. Notably, the half-life of the newly observed (7/2−1) isomeric state in 37Si was measured to be 9.1(7) ns. The half-life of the previously observed closely-lying (3/2−1) state at 156 keV was determined to be 3.20(4) ns, consistent with previously reported values. Reduced ground-state transition probabilities associated with the gamma-ray decay from these excited states were in agreement with results obtained from shell model calculations. In addition to the investigation of isomeric states in 37Si, isomeric 0+ states in 34Si and 32Mg nuclei belonging to the N = 20 “island of inversion” were characterized and searched for, respectively. The isomeric 0+ state in 34Si was populated following the beta decay of implanted 34Mg ions and its 34Al daughter nucleus. Similarly, the 0+ state in 32Mg was searched for via the beta-delayed one neutron emission decay of implanted 33Na ions.

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