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Full-Text Articles in Stars, Interstellar Medium and the Galaxy

The Meaning Of Dark, Light And Shadows: Inferences In Art, Materiality And Cultural Practices, Frank Prendergast Jan 2022

The Meaning Of Dark, Light And Shadows: Inferences In Art, Materiality And Cultural Practices, Frank Prendergast

Book/Book Chapter

Our visual awareness relies on light acting on the eye to perceive materiality and colour. Medieval thought wrestled to articulate and comprehend its nature. The notebooks of Leonardo Da Vinci, for example, included his descriptions to define light and make comparisons so as to differentiate between light and shadow. His focus was on the illumination of surfaces from the perspective of a painter, seeing shadows as ‘the diminution of light by the intervention of an opaque body’ and ‘the counterpart of luminous rays’. In his mind, a shadow ‘stood between light and darkness’, with darkness being ‘the absence of light’. …


Using Methanol Masers To Probe High Mass Star Forming Regions, Naomi S. Shechter, Anuj P. Sarma Aug 2021

Using Methanol Masers To Probe High Mass Star Forming Regions, Naomi S. Shechter, Anuj P. Sarma

DePaul Discoveries

Compared to low mass stars, the formation of high mass stars is not well understood. To understand better how high mass stars form, we can utilize masers, naturally amplified point sources of microwave radiation. One example is the methanol maser, which falls into two categories. Class I methanol masers form in the bipolar outflows from the protostar, and Class II masers form in the accretion disk. Their compact size and intensity make them an excellent source of information about the process of high mass star formation. We compiled a modest database of Class I and II methanol masers through a …


Thinking Out Loud On Early Creation Through The Lens Of Hermeneutics Of Sherlock Holmes (Towards A Model Of Universe Based On Turbulence-Generated Sound Theory), Victor Christianto, Florentin Smarandache Jan 2018

Thinking Out Loud On Early Creation Through The Lens Of Hermeneutics Of Sherlock Holmes (Towards A Model Of Universe Based On Turbulence-Generated Sound Theory), Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In recent years, apparently the Big Bang as described by the Lambda CDM-Standard Model Cosmology has become widely accepted by majority of physics and cosmology communities. Even some people have concluded that it has no serious alternative in horizon. Is that true? First, as we argued elsewhere, Big Bang story relies on singularity. In other words, when we are able to describe the observed data without invoking singularity, then Big Bang model is no longer required. Therefore, here we explore a few alternative stories other than Big Bang story, which most cosmologists believe it is the nearest to Biblical account …


Energy From Active Galactic Nuclei And The Effects On Host Spiral Galaxies, Amanda Schilling Dec 2017

Energy From Active Galactic Nuclei And The Effects On Host Spiral Galaxies, Amanda Schilling

Graduate Theses and Dissertations

I have investigated the energy output of active galactic nuclei (AGN) in order to understand how these objects evolve and the impact they may have on host galaxies. First, I looked at a sample of 96 AGN at redshifts $z \sim 2, 3,$ and $4$ which have imaging and thus luminosity measurements in the $griz$ and $JHK$ observed wavebands. For these galaxies, I have co-epochal data across those bands which accounted for variability in AGN luminosity. I used the luminosity measurements in the five bands to construct spectral energy distributions (SED) in the emitted optical-UV bands for each AGN. I …


Accuracy And Stability Of Integration Methods For Neutrino Transport In Core Collapse Supernovae, Kyle A. Gregory May 2017

Accuracy And Stability Of Integration Methods For Neutrino Transport In Core Collapse Supernovae, Kyle A. Gregory

Chancellor’s Honors Program Projects

No abstract provided.


Stellar Spectroscopy: New Methods And Insights, Sanaz S. Golriz Apr 2015

Stellar Spectroscopy: New Methods And Insights, Sanaz S. Golriz

Electronic Thesis and Dissertation Repository

The study of the chemical evolution of stars is of crucial importance since they play a major role in the enrichment of the chemistry of the universe. Throughout their lifetime, stars undergo several processes that can alter their chemistry. Gradually, the nucleosynthesis products from the interior of the star are radiatively and convectively levitated and mixed with the upper layers of the atmosphere. In the later stages of their evolution, low to intermediate mass stars (0.8-8.0~M☉) eject a significant fraction of these nucleosynthesis products, resulting in a circumstellar envelope of gas and dust around the central star with a very …


Superfluidity In Neutron Stars, Samuel J. Witte Mar 2013

Superfluidity In Neutron Stars, Samuel J. Witte

Undergraduate Theses—Unrestricted

Nucleon pairing is studied with specific considerations directed toward the possible influence on neutron star cooling. We present an in-depth analysis of BCS theory using realistic nuclear potentials and consider the impact short-range correlations can have on the gap. Gap calculations are incorporated into neutron star cooling simulations and the significance of the 3P2 −3F2 channel in various hadronic cooling models is closely examined. An analysis of the 1S0 gap in neutron matter suggests short-range correlations can drastically alter the magnitude, density range, and temperature dependence of the gap. While the newly constructed 1S0 gap does not significantly alter the …