Gravitational Waves from Rotating Neutron Stars and Compact Binary Systems

It is widely anticipated that the first direct detections of gravitational waves will be made by advanced gravitational-wave detectors, such as the two Laser Interferometer Gravitational-wave Observatories (LIGO) and the Virgo interferometer. In preparation for the advanced detector era, I have worked on both detection and post-detection efforts involving two gravitational wave sources: isolated rotating neutron stars (NSs) and compact binary coalescences (CBCs). My dissertation includes three main research projects: 1) a population synthesis study assessing the detectability of isolated NSs, 2) a CBC search for intermediate-mass black-hole binaries (IMBHBs), and 3) new methods for directly measuring the neutron-star (NS) equation of state (EOS). Direct detections of gravitational waves will enrich our current astrophysical knowledge. One such contribution will be through population synthesis of isolated NSs. My collaborators and I show that advanced gravitational-wave detectors can be used to constrain the properties of the Galactic NS population. Gravitational wave detections can also shine light on a currently mysterious astrophysical object: intermediate mass black holes. In developing the IMBHB search, we performed a mock data challenge where signals with total masses up to a few hundred solar masses were injected into recolored data from LIGO’s sixth science run. Since this is the first time a matched filter search has been developed to search for IMBHBs, I discuss what was learned during the mock data challenge and how we plan to improve the search going forward. The final aspect of my dissertation focuses on important post-detection science. I present results for a new method of directly measuring the NS EOS. This is done by estimating the parameters of a 4-piece polytropic EOS model that matches theoretical EOS candidates to a few percent. We show that advanced detectors will be capable of measuring the NS radius to within a kilometer for stars with canonical masses. However, this can only be accomplished with binary NS waveform models that are accurate to the rich EOS physics that happens near merger. We show that the waveforms typically used to model binary NS systems result in unavoidable systematic error that can significantly bias the estimation of the NS EOS

The 18th and 19th century Cree landscape of west central Saskatchewan : implications for archaeology

The eighteenth and nineteenth century Crees of west central Saskatchewan are the focus of this thesis. This research has involved obtaining information relating to the cultural landscape of these Crees for the period encompassed by the study. An examination of one aspect of this cultural landscape, the named landscape, has been the primary aim of this research. Information regarding the named landscape of these Crees was obtained from relevant historic documents and ethnographic research. A number of historic documents have been consulted in this study. In particular, much use has been made of the journal accounts of Hudson's Bay Company traders who travelled to the study region in the mid 1700s. Ethnographic fieldwork was undertaken with elders from several of the study region's Cree communities who provided information on the traditional named landscape. The relationship that existed historically between the Crees of west central Saskatchewan and their landscape is the subject of this thesis. How this information relates to archaeological interpretations in the study region has also been considered. Guiding this research has been an approach which considers the cultural landscape as representing a socially construed space. An examination of named localities from the study area indicates that the named landscape of the region's Crees did not significantly change over the course of the eighteenth and nineteenth centuries. This suggests that the relationship of these Crees to their landscape, how they conceptualized, structured and organized this environment, also remained largely unchanged throughout this period

Continuous Gravitational Waves from Isolated Galactic Neutron Stars in the Advanced Detector Era

We consider a simulated population of isolated Galactic neutron stars. The rotational frequency of each neutron star evolves through a combination of electromagnetic and gravitational wave emission. The magnetic field strength dictates the dipolar emission, and the ellipticity (a measure of a neutron star's deformation) dictates the gravitational wave emission. Through both analytic and numerical means, we assess the detectability of the Galactic neutron star population and bound the magnetic field strength and ellipticity parameter space of Galactic neutron stars with or without a direct gravitational wave detection. While our simulated population is primitive, this work establishes a framework by which future efforts can be conducted.Comment: Accepted for publication by Physical Review D, 8 pages, 5 figure