Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Physical Sciences and Mathematics
Measurements And Mitigation Of Scattered Light Noise In Ligo, Corey Daniel Austin
Measurements And Mitigation Of Scattered Light Noise In Ligo, Corey Daniel Austin
LSU Doctoral Dissertations
The Advanced LIGO (aLIGO) detectors use 1064 nm lasers to measure the tiny fluctuations in spacetime that occur when gravitational waves pass through the earth. LIGO makes use of advanced coating methods and materials to limit the amount of light that scatters from the main beam, but some amount of light does scatter. This stray light can interact with surfaces inside the interferometer that are not seismically isolated and then recombine with the main beam, introducing excess noise into the gravitational wave channel. This thesis reviews the methods for modeling scattered light with ray tracing software and analytical models, for …
Calibration Transients In Ligo Detectors, Thomas Daniel Abbott
Calibration Transients In Ligo Detectors, Thomas Daniel Abbott
LSU Doctoral Dissertations
This dissertation describes a novel method of analyzing fluctuations in the time-dependent calibration models of the LIGO interferometers to estimate their effect on strain reconstruction for gravitational-wave detections. The time-dependence of the calibration model of each detector is tracked with a set of parameters which are continuously measured while the interferometers are operating. These parameters track slow variations in the sensing function of the detectors as well as the actuators that hold the detectors in an operational state. The time-dependent parameter data during the second observation run (O2 [November 30, 2016 16:00 UTC to August 25, 2017 22:00:00 UTC]) and …
Stellar Nucleosynthesis: Direct Measurement Of The Neutron-Capture Cross Sections Of Stable Germanium Isotopes And Design Of A Next Generation Ion Trap For The Study Of Beta-Delayed Neutron Emission, Alexander Laminack
LSU Doctoral Dissertations
Knowledge of stellar nuclear reaction rates is critical to understanding the cosmic origins of the abundances of elements. In order to determine these reaction rates, accurate measurements of nuclear cross sections are needed. This thesis presents the results of an experiment to directly measure the neutron capture cross sections of 70-Ge, 72-Ge, 74-Ge, and 76-Ge. These measurements were performed at the Los Alamos Neutron Science CEnter (LANSCE) using the Detector for Advanced Neutron Capture Experiments (DANCE). This is the first direct measurement for many of these isotopes across the neutron energy spectrum of 10 eV to 1 MeV using the …