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Leds And Astronomy, Britny N. Delp, Stephen M. Pompea 2012 National Optical Astronomy Observatory

Leds And Astronomy, Britny N. Delp, Stephen M. Pompea

STAR Program Research Presentations

Using a Czerny-Turner spectrometer, 45 different types of outdoor lights were categorized. These spectra were used to determine how useful the light is to human eyes and how dark skies friendly these lights are. Dark skies friendly lighting means that little to no light shines above a right angle to the light, and should emit as little as possible below 500nm (green) wavelengths. The short wavelengths present a problem to astronomers in the form of Rayleigh scattering. The following criterion were used in selecting the best source for urban and rural lighting: color rendition measured by color rendering index (CRI), …


Essentials Of The Theory Of Abstraction - Lecture, Subhajit Kumar Ganguly 2012 SelectedWorks

Essentials Of The Theory Of Abstraction - Lecture, Subhajit Kumar Ganguly

Subhajit Kumar Ganguly

In not favouring solutions or sets of solutions, the principle of zero-postulation drives away any unwanted incompleteness from the description of the world. It is the interactions between the possible exhaustive set of solutions that creates the impression pointedness or directiveness in the universe, leading to the formation of clusters, as discussed earlier. These interactions may be chaotic in nature, giving rise to attractor points where the directiveness inside any given system asymptotically seem to approach. It is this directiveness, in turn, inside a given system or in the universe as a whole, that is the cause of all known …


A Possible Detection Of Occultation By A Proto-Planetary Clump In Gm Cephei, W. P. Chen, S. C.-L. Hu, R. Errmann, Ch. Adam, Laurence A. Marschall 2012 Gettysburg College

A Possible Detection Of Occultation By A Proto-Planetary Clump In Gm Cephei, W. P. Chen, S. C.-L. Hu, R. Errmann, Ch. Adam, Laurence A. Marschall

Physics and Astronomy Faculty Publications

GM Cep in the young (~ 4 Myr) open cluster Trumpler 37 has been known to be an abrupt variable and to have a circumstellar disk with very active accretion. Our monitoring observations in 2009–2011 revealed the star to show sporadic ?are events, each with brightening of . 0.5 mag lasting for days. These brightening events, associated with a color change toward the blue, should originate from an increased accretion activity. Moreover, the star also underwent a brightness drop of ~ 1 mag lasting for about a month, during which the star became bluer when fainter. Such brightness drops seem …


New Methods For The Discovery And Characterization Of Lunar Lava Tubes Using Lunar Reconnaissance Orbiter Data, Jonathan Arthur Meyer 2012 University of Texas at El Paso

New Methods For The Discovery And Characterization Of Lunar Lava Tubes Using Lunar Reconnaissance Orbiter Data, Jonathan Arthur Meyer

Open Access Theses & Dissertations

Lava tubes have the potential to serve as a sustainable solution to long-term lunar habitation by providing protection from radiation and micrometeorite bombardment while potentially providing resources in the form of trapped water ice. They also pose compelling science targets in their own right. While the potential benefits of utilizing lunar lava tubes is clear, their discovery is less straightforward. Formation processes for lava tubes do not always result in a surface expression, making their discovery using remotely sensed imagery difficult. Furthermore, there is the potential for lava tubes to be covered by secondary lava flows, impact ejecta, or other …


Numerical Modeling Of Tectonics And Fault Activity Of Icy Satellites, John Olgin 2012 University of Texas at El Paso

Numerical Modeling Of Tectonics And Fault Activity Of Icy Satellites, John Olgin

Open Access Theses & Dissertations

Enceladus, one of the satellites of Saturn, exhibits evidence of recent fault activity, which may be due to gravitational fluctuations, or tidal stresses, generated by its orbit around Saturn. Recent Cassini spacecraft observations of Enceladus reveal water-ice plume activity at the south polar region, originating from locations that correlate with four geologically young, linear fracture-like features, named the "tiger stripes". It is the goal of this investigation to determine the ideal geophysical and geological factors (e.g., fault depths, frictional coefficients, ice layer thickness, ocean layer thickness, tidal stress sources) that support fault activity on Enceladus. The core of this work …


Quantization And Discretization At Large Scales, Florentin Smarandache, Victor Christianto, Pavel Pintr 2012 University of New Mexico

Quantization And Discretization At Large Scales, Florentin Smarandache, Victor Christianto, Pavel Pintr

Branch Mathematics and Statistics Faculty and Staff Publications

The ongoing search of extrasolar planets is one of the most attractive fields of research in astrophysics and astronomy. Up to now, 360 extrasolar planets have been discovered near stars with similar mass as the Sun. There is also discovery related to the so-called Earth-like planets. With regards to these discoveries, one intriguing question is whether there is relationship between orbit distance of the planets and their stars. Various formulas have been suggested since 1990s, and they suggest that there may be reason to accept quantization of distances of those planets both in our solar system and also in extrasolar …


Vacuum, Space-Time, Matter And The Models Of Smarandache Geometry, Florentin Smarandache, Hu Chang-Wei 2012 University of New Mexico

Vacuum, Space-Time, Matter And The Models Of Smarandache Geometry, Florentin Smarandache, Hu Chang-Wei

Branch Mathematics and Statistics Faculty and Staff Publications

Many fundamental concepts in physics remain unsolved:  What is time? Is it pure relative?  What is the vacuum? Is it void space or special medium?  What is mass? Can it be created? I believe that physicists have not got definite answers for the above questions. Isaac Newton said: I was like a boy playing on the sea-shore, and diverting myself now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me. For instance, we still do not know what the clear definition of time …


Characterization Of Thrust Faults On The Moon Using Fault Dynamics And 3d Visualizations, Jaclyn Danielle Clark 2012 University of Texas at El Paso

Characterization Of Thrust Faults On The Moon Using Fault Dynamics And 3d Visualizations, Jaclyn Danielle Clark

Open Access Theses & Dissertations

Many small, lobate scarps, interpreted to be the surface traces of thrust faults, have been found all over Earth's moon by previous researchers. Fault dynamical calculations, assuming an initially completely molten Moon, have shown that these scarps can form due to compressional stresses that accumulate over time as the result of large-scale contraction of the Moon as it cooled. With high-resolution images from the Lunar Reconnaissance Orbiter Camera (LROC), previously undetected lobate scarps can be found globally and viewed at high resolution. By investigating these fault scarps, we can determine better constraints on the amount of crustal shortening and improve …


Phreatomagmatic Activity On The Moon: Possibility Of Pseudocraters At Mare Frigoris, Jose Humberto Garcia 2012 University of Texas at El Paso

Phreatomagmatic Activity On The Moon: Possibility Of Pseudocraters At Mare Frigoris, Jose Humberto Garcia

Open Access Theses & Dissertations

The discovery of water on the Moon raises the possibility that lava-water, or phreatomagmatic, interactions have occurred on the lunar surface in the past. Such interactions may have formed pseudocraters, crater-like landforms that result from steam explosions that occur when lava flows come in contact with surface or near-surface water or ice. We present a study of Mare Frigoris, a volcanic plain just north of the Mare Imbrium impact basin on the Moon. Clusters of irregular, circular features on the basaltic lava flows in this area resemble pseudocrater fields in Iceland, and they are located in a region with inferred …


Analysis Of The Hinode Magnetograms, Tae K. Kim, Marina Geneva, Julia Reich, Stefan Wolff 2011 University of Alabama in Huntsville

Analysis Of The Hinode Magnetograms, Tae K. Kim, Marina Geneva, Julia Reich, Stefan Wolff

Von Braun Symposium Student Posters

No abstract provided.


Lunar Occultation Observer: A Nuclear Astrophysics All-Sky Survey Mission Concept, Riley Freelove 2011 University of Alabama in Huntsville

Lunar Occultation Observer: A Nuclear Astrophysics All-Sky Survey Mission Concept, Riley Freelove

Von Braun Symposium Student Posters

No abstract provided.


Veritas Observations Of The Unusual Extragalactic Transient Swift J164449.3+573451, P. T. Reynolds, et al 2011 Department of Physical Sciences, Cork Institute of Technology, Bishopstown, Cork, Ireland

Veritas Observations Of The Unusual Extragalactic Transient Swift J164449.3+573451, P. T. Reynolds, Et Al

Physical Sciences Publications

We report on very high energy (>100 GeV) gamma-ray observations of Swift J164449.3+573451, an unusual transient object first detected by the Swift Observatory and later detected by multiple radio, optical, and X-ray observatories. A total exposure of 28 hr was obtained on Swift J164449.3+573451 with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) during 2011 March 28-April 15. We do not detect the source and place a differential upper limit on the emission at 500 GeV during these observations of 1.4 × 10–12 erg cm–2 s–1 (99% confidence level). We also present time-resolved upper limits and use a …


Evaluating Explicit Methods For Solving Astrophysical Nuclear Reaction Networks, Elisha Don Feger 2011 University of Tennessee - Knoxville

Evaluating Explicit Methods For Solving Astrophysical Nuclear Reaction Networks, Elisha Don Feger

Doctoral Dissertations

Many systems of physical interest are difficult to manage computationally because of the intrinsic nature of the equations that govern them. Many of these systems of equations are stiff, meaning that the standard approach to solving them is with implicit methods, because explicit methods either are unstable or require timesteps too small to be computationally efficient. Presented here is a study of explicit methods that decouple stability from accuracy under certain conditions, allowing for larger timesteps to be taken.


Laboratory Astrophysics: Using Ebit Measurements To Interpret High Resolution Spectra From Celestial Sources, Carey Scott, Joshua Thompson, N. Hell, Greg V. Brown 2011 California State University - Chico

Laboratory Astrophysics: Using Ebit Measurements To Interpret High Resolution Spectra From Celestial Sources, Carey Scott, Joshua Thompson, N. Hell, Greg V. Brown

STAR Program Research Presentations

Astrophysicists use radiation to investigate the physics controlling a variety of celestial sources, including stellar atmospheres, black holes, and binary systems. By measuring the spectrum of the emitted radiation, astrophysicists can determine a source’s temperature and composition. Accurate atomic data are needed for reliably interpreting these spectra. Here we present an overview of how LLNL’s EBIT facility is used to put the atomic data on sound footing for use by the high energy astrophysics community.


Supernova Remnants And Cosmic Ray Acceleration Mechanisms, Ariel L. Simons, Yasunobu Uchiyama 2011 University of California - Irvine

Supernova Remnants And Cosmic Ray Acceleration Mechanisms, Ariel L. Simons, Yasunobu Uchiyama

STAR Program Research Presentations

Supernova remnants (SNRs) are considered to be the primary energy source of galactic-origin cosmic rays. Within this prediction exist two models, leptonic and hadronic, to explain the acceleration of charged particles up to a PeV in energy. Using data from the Fermi Gamma-ray Space Telescope (FGST) each model is expected to produce a distinct spectral energy distribution (SED) over a photon energy range of 100MeV to 100GeV. This analysis is focused on the methods for generating SEDs for the SNR Cassiopeia A and how they can be used to constrain the likelihood of either acceleration model.


The Study Of Variability In Oxygen-Rich Proto-Planetary Nebulae, Kristie Shaw 2011 Valparaiso University

The Study Of Variability In Oxygen-Rich Proto-Planetary Nebulae, Kristie Shaw

Symposium on Undergraduate Research and Creative Expression (SOURCE)

In this project, I am studying and analyzing the light and color variations for two proto-planetary nebulae (PPNe). PPNe is a stage in a star’s life where the star is in the process of losing its outer layers and exposing its core. I observed at the Valparaiso University Observatory, using the 0.4 meter telescope and an electronic camera to take digital images. I reduced these data using an image processing program to get the numerical data results. I plotted these results as a light curve showing the variation in brightness of the star versus time. By observing in three different …


The Effect Of Strong Electrostatic And Magnetostatic Fields On The Activity Of Radioactive Nuclides, Sam Schaub 2011 Valparaiso University

The Effect Of Strong Electrostatic And Magnetostatic Fields On The Activity Of Radioactive Nuclides, Sam Schaub

Symposium on Undergraduate Research and Creative Expression (SOURCE)

This experiment seeks to measure the effect of strong electrostatic and magnetostatic fields on the decay constant of short-lived radioactive isotopes. Though it is assumed in modern radioactivity theory that such fields should not have any measurable effect, conclusive evidence utilizing modern equipment is absent from published literature. Samples have been monitored that exhibit beta-minus, beta-plus, electron capture, and internal conversion modes of radioactive decay. Radioactive nuclides chosen for this study include I-128, Cs-134, and Cu-64. The half-lives in this collection of radioactive nuclides range from 25 minutes to 12.7 hours. Sodium Iodide detectors are used to monitor the samples …


Three Channel Polarimetric Based Data Deconvolution, Kurtis G. Engelson 2011 Air Force Institute of Technology

Three Channel Polarimetric Based Data Deconvolution, Kurtis G. Engelson

Theses and Dissertations

A three channel polarimetric deconvolution algorithm was developed to mitigate the degrading effects of atmospheric turbulence in astronomical imagery. Tests were executed using both simulation and laboratory data. The resulting efficacy of the three channel algorithm was compared to a recently developed two channel approach under identical conditions ensuring a fair comparison amongst both algorithms. Two types of simulations were performed. The first was a binary star simulation to compare resulting resolutions between the three and two channel algorithms. The second simulation measured how effective both algorithms could deconvolve a blurred satellite image. The simulation environment assumed the key parameters …


Condensation States And Landscaping With The Theory Of Abstraction, Subhajit Kumar Ganguly 2011 SelectedWorks

Condensation States And Landscaping With The Theory Of Abstraction, Subhajit Kumar Ganguly

Subhajit Kumar Ganguly

The Abstraction theory is applied in landscaping. A collection of objects may be made to be vast or meager depending upon the scale of observations. This idea may be developed to unite the worlds of the great vastness of the universe and the minuteness of the sub-atomic realm. Keeping constant a scaling ratio for both worlds, these may actually be converted into two self-same representatives with respect to scaling. The Laws of Physical Transactions are made use of to study Bose-Einstein condensation. As the packing density of concerned constituents increase to a certain critical value, there may be evolution of …


Star Formation In M33 (Herm33es), C. Kramer, M. Boquien, J. Braine, C. Buchbender, Daniela Calzetti, P. Gratier, B. Mookerjea, M. Relaño, S. Verley 2011 University of Massachusetts - Amherst

Star Formation In M33 (Herm33es), C. Kramer, M. Boquien, J. Braine, C. Buchbender, Daniela Calzetti, P. Gratier, B. Mookerjea, M. Relaño, S. Verley

Daniela Calzetti

Within the key project "Herschel M33 extended survey" (HerM33es), we are studying the physical and chemical processes driving star formation and galactic evolution in the nearby galaxy M33, combining the study of local conditions affecting individual star formation with properties only becoming apparent on global scales. Here, we present recent results obtained by the HerM33es team. Combining Spitzer and Herschel data ranging from 3.6um to 500um, along with HI, Halpha, and GALEX UV data, we have studied the dust at high spatial resolutions of 150pc, providing estimators of the total infrared (TIR) brightness and of the star formation rate. While …


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