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Diagnostics Of Energy Release In Solar Flares With Radio Dynamic Imaging Spectroscopy, Yingjie Luo

Dissertations

Studies of the magnetic energy release and conversion process lie at the core of solar flare physics. Radio observations serve as a unique diagnostic method. In this dissertation, taking advantage of broadband radio dynamic imaging spectroscopy observations made by the Karl G. Jansky Very Large Array (VLA), studies are carried out on the flare energy release processes using different types of radio emissions.

The VLA is a general-purpose radio observatory located in New Mexico, which provides high-quality radio dynamic imaging spectroscopic observations with an ultra-fast time cadence. In the first study, stochastic decimetric radio spike bursts are observed by the …

Waves And Oscillations In A Sunspot: Observations And Modeling Of Noaa Ar 12470, Yi Chai

Dissertations

Waves and oscillations are important solar phenomena not only because they can propagate and dissipate energy in the chromosphere, but also because they carry information about the structure of the atmosphere in which they propagate. Among these phenomena, the one of the most interesting ones occurs in the sunspot umbra. In this area, continuously propagating magnetohydrodynamic (MHD) waves generated from below the photosphere create the famous 3-minute sunspot umbral oscillations that affect the line profile of spectral lines due to temperature, density, and velocity changes of the plasma in the region. In the past decades, numerous observations and models have …

Determination Of Galaxy Cluster Masses Via Sunyaev-ZelʹDovich Effect Observations, Ashley E. Lindley

Dissertations

A powerful method for investigating cosmology is to observe the evolution of clusters over time, accomplished through analysis of cluster properties over a range of redshifts. One important property to examine is the cluster mass function, i.e., the number density of clusters of a given mass at a given redshift range. Studies of the evolution of the cluster mass function over redshift ranges are used for obtaining cosmological constraints. To expand our mass knowledge to higher redshifts, a robust method for determining cluster masses utilizing radio data is desired. Presented within this dissertation are measurements of the Sunyaev-Zel'dovich Effect (SZE) …