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On The Detection Of Exoplanets Via Radial Velocity Doppler Spectroscopy, Joseph P. Glaser 2015 Cleveland State University

On The Detection Of Exoplanets Via Radial Velocity Doppler Spectroscopy, Joseph P. Glaser

The Downtown Review

Since the discovery of the first exoplanet occurred in the late 1980s, physicists and astronomers have confirmed the existence of over 1783 planets orbiting other stars. Over the years, several methods have been developed for detecting these celestial systems, but none has thus far been more successful than the use of Radial Velocity Doppler Spectroscopy. As such, this paper attempts to break down the barriers placed before new entries into the field by detailing the theoretical premise and experimental process of this most successful technique. The content enclosed is geared for the senior undergraduate student with some knowledge of vector-based ...


Alignment Of The Western And Eastern Passage Tombs At Knowth Tomb 1, Frank Prendergast, Tom Ray 2015 Dublin Institute of Technology

Alignment Of The Western And Eastern Passage Tombs At Knowth Tomb 1, Frank Prendergast, Tom Ray

Book/Book Chapter

This report presents a summary account of two surveys undertaken by the authors to determine and interpret the alignments of the western and eastern passage tombs at Knowth, Co. Meath. The findings indicate that contrary to earlier suggestions, the eastern passage and the western passage (inner and outer) are not aligned towards sunrise and sunset respectively at the period of the vernal and autumnal equinoxes.


The Formation Of The Trajectories Of The Planets Of The Solar System, Vildyan Yanbikov 2015 Yanbikov Vildyan Shavkyatovich

The Formation Of The Trajectories Of The Planets Of The Solar System, Vildyan Yanbikov

Vildyan Yanbikov

В начальный момент возникновения Солнечной системы. Планеты вращались вокруг Солнца по круговым орбитам. Предположим, что сила притяжения планеты к Солнцу из-за сферически-симметричных гравитационных волн. Солнце излучает эти волны с определенной постоянной частотой n. На планете падает суперпозиции волн, испускаемых веществом, которое состоит из Солнца. Эти волны распространяются со скоростью света в вакууме. Введите в абсолютном пространстве, абсолютной системы отсчета. Эта система фиксируется относительно абсолютного пространства. Пусть Солнечная система движется со скоростью V относительно абсолютного пространства. Введем систему отсчета X Y Z. солнце находится в начале координат этой системы отсчета.


Rainich-Type Conditions For Perfect Fluid Spacetimes, Dionisios Krongos, Charles G. Torre 2014 Utah State University

Rainich-Type Conditions For Perfect Fluid Spacetimes, Dionisios Krongos, Charles G. Torre

Research Vignettes

In this worksheet we describe and illustrate a relatively simple set of new Rainich-type conditions on an n-dimensional spacetime which are necessary and sufficient for it to define a perfect fluid solution of the Einstein field equations. Procedures are provided which implement these Rainich-type conditions and which reconstruct the perfect fluid from the metric. These results provide an example of the idea of geometrization of matter fields in general relativity, which is a purely geometrical characterization of matter fields via the Einstein field equations.


Star Cluster Populations In Compact Groups Of Galaxies, Konstantin Fedotov 2014 The University of Western Ontario

Star Cluster Populations In Compact Groups Of Galaxies, Konstantin Fedotov

University of Western Ontario - Electronic Thesis and Dissertation Repository

In this thesis, I have explored the star cluster populations of several compact groups of galaxies, based on observations with the Advanced Camera for Surveys and the Wide Field Camera 3 on the Hubble Space Telescope. Low velocity dispersions and high galaxy number densities, the conditions of compact groups (in particular Hickson Compact Groups), represent an environment with frequent and prolonged interactions. Such environment can trigger the formation of star cluster populations associated with specific events. The BVI study has shown that star clusters can be used as a powerful tool for studying such events triggered by mergers and tidal ...


Scale-Up Methodology For Bench-Scale Slurry Photocatalytic Reactors Using Combined Irradiation And Kinetic Modelling, Patricio J. Valades Pelayo 2014 The University of Western Ontario

Scale-Up Methodology For Bench-Scale Slurry Photocatalytic Reactors Using Combined Irradiation And Kinetic Modelling, Patricio J. Valades Pelayo

University of Western Ontario - Electronic Thesis and Dissertation Repository

The present study focuses on developing a predictive methodology to scale-up a slurry annular photoreactor using a TiO2 Degussa P25 from the bench-scale to a pilot-plant scale. The bench-scale photoreactor is a Photo-CREC-Water II, a 2.65 L internally-irradiated slurry annular photocatalytic reactor. The pilot-plant scale photoreactor is a Photo-CREC Water Solar Simulator, a 9.8 L pilot-plant photoreactor, externally irradiated by eight lamps.

The adopted methodology allows the independent validation of radiative and kinetic models avoiding cross-correlation issues. The proposed approach involves two Monte Carlo methods, to model the Radiative Transfer Equation (RTE) inside each photoreactor. With this ...


Should We Love Or Hate Big Data? The Good, The Bad, And The Ugly, Dennis Crossen M.Sc., MBA, Karti Puranam PhD, Madjid Tavana PhD 2014 La Salle University

Should We Love Or Hate Big Data? The Good, The Bad, And The Ugly, Dennis Crossen M.Sc., Mba, Karti Puranam Phd, Madjid Tavana Phd

Explorer Café

No abstract provided.


The Optical Luminosity Function Of Gamma-Ray Bursts Deduced From Rotse-Iii Observations, X. H. Cui, X. F. Wu, J. J. Wei, F. Yuan, W. K. Zheng, E. W. Liang, C. W. Akerlof, M. C. B. Ashley, H A. Flewelling, E. Göǧüş, T. Güver, Ü. Kızıloǧlu, T. A. McKay, S. B. Pandey, E. S. Rykoff, W. Rujopakarn, B. E. Schaefer, J. C. Wheeler, Sarah A. Yost 2014 College of Saint Benedict/Saint John's University

The Optical Luminosity Function Of Gamma-Ray Bursts Deduced From Rotse-Iii Observations, X. H. Cui, X. F. Wu, J. J. Wei, F. Yuan, W. K. Zheng, E. W. Liang, C. W. Akerlof, M. C. B. Ashley, H A. Flewelling, E. Göǧüş, T. Güver, Ü. Kızıloǧlu, T. A. Mckay, S. B. Pandey, E. S. Rykoff, W. Rujopakarn, B. E. Schaefer, J. C. Wheeler, Sarah A. Yost

Physics Faculty Publications

We present the optical luminosity function (LF) of gamma-ray bursts (GRBs) estimated from a uniform sample of 58 GRBs from observations with the Robotic Optical Transient Search Experiment III (ROTSE-III). Our GRB sample is divided into two sub-samples: detected afterglows (18 GRBs) and those with upper limits (40 GRBs). We derive R-band fluxes for these two sub-samples 100 s after the onset of the burst. The optical LFs at 100 s are fitted by assuming that the co-moving GRB rate traces the star formation rate. While fitting the optical LFs using Monte Carlo simulations, we take into account the ...


Nasa's Search For Life Beyond The Earth, John W. Delano Prof 2014 UAlbany

Nasa's Search For Life Beyond The Earth, John W. Delano Prof

Department of Atmospheric and Environmental Science Faculty Scholarship

Invited presentation (November 3, 2014 for the 119th Annual Conference of the Science Teachers Association of New York State) provides an overview of NASA's search for worlds orbiting other nearby stars on the Milky Way galaxy.


Two Stellar Populations In The Distant Milky Way Globular Cluster Ngc2419, Stephen D. Gillam Dr, Sydnee Hamrick, Christian Keating 2014 IPFW

Two Stellar Populations In The Distant Milky Way Globular Cluster Ngc2419, Stephen D. Gillam Dr, Sydnee Hamrick, Christian Keating

Physics Faculty Presentations

The distant Milky Way globular cluster NGC2419 holds the fossil record of dark matter in the early universe. NGC2419 is 13 GYr old. It is thought that globular clusters are the remnants of giant spheroidal stars systems that formed under the gravitational influence of dark matter 13 GYr ago. Winds from supernovae and/or rotating asymptotic giant branch stars removed, in less than 1 Gyr, most of their stars and much of the gas from which new stellar generations form. These winds enriched the primordial gas in carbon+nitrogen+oxygen and helium. The amount of gas that remained de-termined how ...


Tracing The Origin Of Presolar Grains: Algorithms To Parametrize Supernovae, Justin M. Finkel 2014 Washington University in St Louis

Tracing The Origin Of Presolar Grains: Algorithms To Parametrize Supernovae, Justin M. Finkel

Undergraduate Research Symposium Posters & Abstracts

Certain meteorites contain grains of stardust with isotopic compositions that suggest supernova origins. Furthermore, individual grains often contain signatures from different zones of the star, from the iron-rich core to the hydrogen- and helium-rich envelope. This implies large-scale mixing between layers, and a grain’s specific combination of isotopic ratios can be used to constrain these mixing mechanisms. To this end we have developed an algorithm which, given a grain’s set of measured isotopic ratios and a theoretical supernova model, assigns ‘mixing fractions’ to various zones of the supernova, indicating what fraction of the grain comes from each zone ...


The Role Of Subsurface Flows In Solar Surface Convection: Modeling The Spectrum Of Supergranular And Larger Scale Flows, J. W. Lord, R. H. Cameron, M. P. Rast, M. Rempel, T. Roudier 2014 University of Colorado, Boulder

The Role Of Subsurface Flows In Solar Surface Convection: Modeling The Spectrum Of Supergranular And Larger Scale Flows, J. W. Lord, R. H. Cameron, M. P. Rast, M. Rempel, T. Roudier

Astrophysical & Planetary Sciences Faculty Contributions

We model the solar horizontal velocity power spectrum at scales larger than granulation using a two-component approximation to the mass continuity equation. The model takes four times the density scale height as the integral (driving) scale of the vertical motions at each depth. Scales larger than this decay with height from the deeper layers. Those smaller are assumed to follow a Kolmogorov turbulent cascade, with the total power in the vertical convective motions matching that required to transport the solar luminosity in a mixing length formulation. These model components are validated using large-scale radiative hydrodynamic simulations. We reach two primary ...


2014 Scas Annual Meeting Program, 2014 University of South Carolina

2014 Scas Annual Meeting Program

Journal of the South Carolina Academy of Science

No abstract provided.


Scas Officers And Council Members 2014-2015, 2014 University of South Carolina

Scas Officers And Council Members 2014-2015

Journal of the South Carolina Academy of Science

No abstract provided.


Table Of Contents, 2014 University of South Carolina

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Intensities, Broadening And Narrowing Parameters In The Ν3 Band Of Methane, Et-touhami Es-sebbar, Aamir Farooq 2014 KAUST

Intensities, Broadening And Narrowing Parameters In The Ν3 Band Of Methane, Et-Touhami Es-Sebbar, Aamir Farooq

Dr. Et-touhami Es-sebbar

The P-branch of methane׳s ν3 band is probed to carry out an extensive study of the 2905–2908 cm−1 infrared spectral region. Absolute line intensities as well as N2-, O2-, H2-, He-, Ar- and CO2-broadening coefficients are determined for nine transitions at room temperature. Narrowing parameters due to the Dicke effect have also been investigated. A narrow emission line-width (~0.0001 cm−1) difference-frequency-generation (DFG) laser system is used as the tunable light source. To retrieve the CH4 spectroscopic parameters, Voigt and Galatry profiles were used to simulate the measured line shape of the individual transitions.


The Meaning Of Wise Colours – I. The Galaxy And Its Satellites, Robert Nikutta, Nicholas Hunt-Walker, Maia M. Nenkova, Željko Ivezić, Moshe Elitzur 2014 University of Kentucky

The Meaning Of Wise Colours – I. The Galaxy And Its Satellites, Robert Nikutta, Nicholas Hunt-Walker, Maia M. Nenkova, Željko Ivezić, Moshe Elitzur

Physics and Astronomy Faculty Publications

Through matches with the Sloan Digital Sky Survey (SDSS) catalogue we identify the location of various families of astronomical objects in WISE colour space. We identify reliable indicators that separate Galactic/local from extragalactic sources and concentrate here on the objects in our Galaxy and its closest satellites. We develop colour and magnitude criteria that are based only on WISE data to select asymptotic giant branch (AGB) stars with circumstellar dust shells, and separate them into O-rich and C-rich classes. With these criteria we produce an all-sky map for the count ratio of the two populations. The map reveals differences ...


Observational Signatures From Self-Gravitating Protostellar Disks, Alexander L. DeSouza 2014 The University of Western Ontario

Observational Signatures From Self-Gravitating Protostellar Disks, Alexander L. Desouza

University of Western Ontario - Electronic Thesis and Dissertation Repository

Protostellar disks are the ubiquitous corollary outcome of the angular momentum conserving, gravitational collapse of molecular cloud cores into stars. Disks are an essential component of the star formation process, mediating the accretion of material onto the protostar, and for redistributing excess angular momentum during the collapse. We present a model to explain the observed correlation between mass accretion rates and stellar mass that has been inferred from observations of intermediate to upper mass T Tauri stars. We explain this correlation within the framework of gravitationally driven torques parameterized in terms of Toomre’s Q criterion. Our models reproduce both ...


Measuring Noble Gases In Coma Samples From Comet Wild 2, Jacob Simones 2014 Minnesota State University, Mankato

Measuring Noble Gases In Coma Samples From Comet Wild 2, Jacob Simones

Journal of Undergraduate Research at Minnesota State University, Mankato

Since comets originated during the formation of the solar system, the processes of solar system formation can be better understood through compositional analysis of cometary material. A low density, silicon-based substance called aerogel was used by NASA’s Stardust spacecraft to collect coma samples from comet Wild 2. Aerogel not from the spacecraft (“non-flight”) was investigated to determine the possibility of measuring noble gases in Stardust samples. Gas evolved from heated, non-flight aerogel was measured initially using a residual gas analyzer, then a high-sensitivity massspectrometer. Levels of helium and neon isotopes observed from both instruments were sufficiently low that noble ...


Automated Image Interpretation For Science Autonomy In Robotic Planetary Exploration, Raymond Francis 2014 The University of Western Ontario

Automated Image Interpretation For Science Autonomy In Robotic Planetary Exploration, Raymond Francis

University of Western Ontario - Electronic Thesis and Dissertation Repository

Advances in the capabilities of robotic planetary exploration missions have increased the wealth of scientific data they produce, presenting challenges for mission science and operations imposed by the limits of interplanetary radio communications. These data budget pressures can be relieved by increased robotic autonomy, both for onboard operations tasks and for decision- making in response to science data.

This thesis presents new techniques in automated image interpretation for natural scenes of relevance to planetary science and exploration, and elaborates autonomy scenarios under which they could be used to extend the reach and performance of exploration missions on planetary surfaces.

Two ...


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