Physical Sciences and Mathematics Commons^™

Measurements Of The 16c + 12c And 16c + 13c Fusion Cross Sections With Implications For Astrophysics, Ashley Ann Hood

LSU Doctoral Dissertations

The fusion of neutron-rich nuclei is of interest to nuclear astrophysics and nuclear structure. X-ray superbursts are powered by runaway thermonuclear burning deep inside of a neutron star, where heating from the pycnonuclear fusion of neutron-rich isotopes is an important heat source. Experimental measurements of fusion cross sections of neutron-rich isotopes have provided insights regarding nucleon transfer and nuclear structure properties affecting fusion. Recently, the ¹⁵C + ¹²C total fusion cross section was measured using a ¹⁵C beam produced by the in-flight beam production facility, which is part of the Argonne Tandem LINAC Accelerator System (ATLAS) at …

High Power And Optomechanics In Advanced Ligo Detectors, Terra Christine Hardwick

LSU Doctoral Dissertations

In September 2015, a new era of astronomy began with the first direct detection of grav- itational waves from a binary black hole coalescence. The event was captured by the Laser Interferometer Gravitational-wave Observatory, comprised of two long-baseline interferometers, one in Livingston, LA and one in Hanford, WA. At the time of the first detection, the interferometers were part way through an upgrade to an advanced configuration and were operating with a strain sensitivity of just better than 10⁻²³/Hz^1/2 around 100Hz. The full Advanced LIGO design calls for sensitivity of a few parts in 10⁻²⁴/Hz …

Alpha Capture Reaction Rates For Nucleosynthesis Within An Ab Initio Framework, Alison Constance Dreyfuss

LSU Doctoral Dissertations

Clustering in nuclear systems has broad impacts on all phases of stellar burning, and plays a significant role in our understanding of nucleosynthesis, or how and where nuclei are produced in the universe. The role of alpha particles in particular is extremely important for nuclear astrophysics: ⁴He was one of the earliest elements produced in the Big Bang, it is one of the most abundant elements in the universe, and helium burning -- in particular, the triple-alpha process -- is one of the most important ``engines'' in stars. To better understand nucleosynthesis and stellar burning, then, it is important …

Exploring Planetary Surfaces With Remote Sensing, Donald R. Hood

LSU Doctoral Dissertations

Aside from Earth, Mars is the most well-explored planetary body in our solar system. Much has been learned about its geologic past including a history of volcanism, ice ages, and potentially long-lasting liquid water. Much of this knowledge of Mars comes from remote observations of the surface and atmosphere from Mars-orbiting satellites. Such remote observations remain the only way to examine the entirety of Mars’ surface as rovers and landers can only examine small areas. The chapters of this work cover three projects that explore the surface of Mars through a variety of remote sensing methods.

In chapter 1, Gamma-ray …

Long-Term Dust Formation By Core Collapse Supernovae, Kelsie Marie Krafton

LSU Doctoral Dissertations

Studying long-term dust formation by CCSNe is an important step toward understanding the large dust masses found in early galaxies. The amazing new discovery of approximately a solar mass of cold dust in the ejecta of SN 1987A has caused a complete re-evaluation of dust formation in core collapse supernovae (CCSNe). CCSNe form only a small amount of dust after three years, but SN 1987A has a dust mass that is several orders of magnitude larger after 25 years. A recent study of SN 2010jl by Gall et al. (2014) made the fascinating suggestion that dust is continuously forming in …