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309 full-text articles. Page 1 of 11.

Computational Astronomy: Classification Of Celestial Spectra Using Machine Learning Techniques, Gayatri Milind Hungund 2020 San Jose State University

Computational Astronomy: Classification Of Celestial Spectra Using Machine Learning Techniques, Gayatri Milind Hungund

Master's Projects

Lightyears beyond the Planet Earth there exist plenty of unknown and unexplored stars and Galaxies that need to be studied in order to support the Big Bang Theory and also make important astronomical discoveries in quest of knowing the unknown. Sophisticated devices and high-power computational resources are now deployed to make a positive effort towards data gathering and analysis. These devices produce massive amount of data from the astronomical surveys and the data is usually in terabytes or petabytes. It is exhaustive to process this data and determine the findings in short period of time. Many details can be missed ...


Automated Spectroscopic Detection And Mapping Using Alma And Machine Learningtechniques, Steven Cocke, Andrew Wilkins, Josephine McDaniel, John Santerre, Conor Nixon 2020 Southern Methodist University

Automated Spectroscopic Detection And Mapping Using Alma And Machine Learningtechniques, Steven Cocke, Andrew Wilkins, Josephine Mcdaniel, John Santerre, Conor Nixon

SMU Data Science Review

In this paper we present a methodology for automating theclassification of spectrally resolved observations of multiple emissionlines with the Atacama Large Millimeter/submillimeter Array (ALMA).Molecules in planetary atmospheres emit or absorb different wavelengthsof light thereby providing a unique signature for each species. ALMAdata were taken from interferometric observations of Titan made be-tween UT 2012 July 03 23:22:14 and 2012 July 04 01:06:18 as part ofALMA project 2011.0.00319.S. We first employed a greedy set cover algorithm to identify the most probable molecules that would reproducethe set of frequencies with respective flux greater than ...


Title: Fully Interactive And Refined Resolution Simulations Of The Martian Dust Cycle By The Marswrf Model, Claus Gebhardt, Abdelgadir Abuelgasim, Ricardo M. Fonseca, Javier Martín-Torres, Maria-Paz Zorzano 2020 United Arab Emirates University

Title: Fully Interactive And Refined Resolution Simulations Of The Martian Dust Cycle By The Marswrf Model, Claus Gebhardt, Abdelgadir Abuelgasim, Ricardo M. Fonseca, Javier Martín-Torres, Maria-Paz Zorzano

National Space Science & Technology Center Datasets

The Mars climate model MarsWRF was run with fully interactive dust parametrization, assuming an infinite surface dust reservoir. Changing the horizontal resolution from 5°×5° to 2°×2° produced different dust cycle variability and dust source regions. The higher spatial resolution allowed for a better representation of the surface topography and associated surface dust lifting by wind stress, that is more consistent with observations. Global Dust Storm Events typically occurred if dust storm activity at northern Hellas Planitia connected with that at southern Chryse Planitia.


Cosmic-Ray Acceleration In The Cygnus Ob2 Stellar Association, Binita Hona 2020 Michigan Technological University

Cosmic-Ray Acceleration In The Cygnus Ob2 Stellar Association, Binita Hona

Dissertations, Master's Theses and Master's Reports

The Cygnus region of our Galaxy consists of an active star forming region and a wealth of various astrophysical sources such as pulsar wind nebulae (PWN), supernova remnants (SNRs), and massive star clusters. Massive stellar clusters and associations have been postulated as possible sources of cosmic rays (CRs) in our Galaxy. One example of a gamma-ray source associated with a stellar association lies in the Cygnus region known as the "Cygnus Cocoon". It is an extended region of gamma-ray emission in the Cygnus X region and attributed to a possible superbubble with freshly accelerated CRs which are hypothesized to produce ...


New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd 2019 University of New Mexico

New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd

Mathematics and Statistics Faculty and Staff Publications

It is widely known among the Frontiers of physics, that “sweeping under the rug” practice has been quite the norm rather than exception. In other words, the leading paradigms have strong tendency to be hailed as the only game in town. For example, renormalization group theory was hailed as cure in order to solve infinity problem in QED theory. For instance, a quote from Richard Feynman goes as follows: “What the three Nobel Prize winners did, in the words of Feynman, was "to get rid of the infinities in the calculations. The infinities are still there, but now they can ...


#7 - Cluster Characterization And Veto Analysis Of The Frequencyhough All-Sky Continuous Gravitational Wave Search, Cain Gantt, Pia Astone 2019 Georgia College and State University

#7 - Cluster Characterization And Veto Analysis Of The Frequencyhough All-Sky Continuous Gravitational Wave Search, Cain Gantt, Pia Astone

Georgia Undergraduate Research Conference (GURC)

Continuous gravitational waves (CWs) can be produced by rotating neutron stars with an asymmetric mass distribution about their axis of rotation. The FrequencyHough search is an all-sky search for these signals, and the large parameter space considered introduces computational limits into the pipeline. We investigate the distributions of candidates produced by earlier stages in the pipeline, and propose the mechanisms within the pipeline that produce these effects. We also characterize the performance of two steps, a veto and ranking procedure, used to reduce the number of candidates within the FrequencyHough pipeline. We found the distance metric in the parameter space ...


Galaxy And Mass Assembly: A Comparison Between Galaxy-Galaxy Lens Searches In Kids/Gama, Shawn Knabel, Benne Holwerda 2019 University of Louisville

Galaxy And Mass Assembly: A Comparison Between Galaxy-Galaxy Lens Searches In Kids/Gama, Shawn Knabel, Benne Holwerda

Posters-at-the-Capitol

Strong gravitational lenses are cases where a distant background galaxy is located directly behind a massive foreground galaxy, whose gravity causes the light from the background galaxy to bend around the foreground galaxy. In addition to being visually stunning, these rare events are useful laboratories for furthering our understanding of gravity and cosmology and to determine properties, such as the mass and dark matter content, of the lensing galaxies themselves. The trouble is finding enough of these strong gravitational lenses for further study. The immensity of the catalogs being collected by state-of-the-art telescopes requires equally innovative methods for interpreting that ...


Large‐Amplitude Mountain Waves In The Mesosphere Observed On 21 June 2014 During Deepwave: 1.Wave Development, Scales, Momentum Fluxes, And Environmental Sensitivity, Michael J. Taylor, Pierre-Dominique Pautet, David C. Fritts, Bernd Kaifler, Steven M. Smith, Yucheng Zhao, Neal R. Criddle, Pattilyn McLaughlin, William R. Pendleton Jr., Michael P. McCarthy, Gonzalo Hernandez, Stephen D. Eckermann, James Doyle, Markus Rapp, Ben Liley, James M. Russell III 2019 Utah State University

Large‐Amplitude Mountain Waves In The Mesosphere Observed On 21 June 2014 During Deepwave: 1.Wave Development, Scales, Momentum Fluxes, And Environmental Sensitivity, Michael J. Taylor, Pierre-Dominique Pautet, David C. Fritts, Bernd Kaifler, Steven M. Smith, Yucheng Zhao, Neal R. Criddle, Pattilyn Mclaughlin, William R. Pendleton Jr., Michael P. Mccarthy, Gonzalo Hernandez, Stephen D. Eckermann, James Doyle, Markus Rapp, Ben Liley, James M. Russell Iii

Publications

A remarkable, large‐amplitude, mountain wave (MW) breaking event was observed on the night of 21 June 2014 by ground‐based optical instruments operated on the New Zealand South Island during the Deep Propagating Gravity Wave Experiment (DEEPWAVE). Concurrent measurements of the MW structures, amplitudes, and background environment were made using an Advanced Mesospheric Temperature Mapper, a Rayleigh Lidar, an All‐Sky Imager, and a Fabry‐Perot Interferometer. The MW event was observed primarily in the OH airglow emission layer at an altitude of ~82 km, over an ~2‐hr interval (~10:30–12:30 UT), during strong eastward winds ...


Searching For Trends In Atmospheric Compositions Of Extrasolar Planets, Kassandra Weber, Paola Rodriguez Hidalgo, Adam Turk, Troy Maloney, Stephen Kane 2019 Humboldt State University

Searching For Trends In Atmospheric Compositions Of Extrasolar Planets, Kassandra Weber, Paola Rodriguez Hidalgo, Adam Turk, Troy Maloney, Stephen Kane

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State University

No abstract provided.


To Apply Or Not To Apply: A Survey Analysis Of Grant Writing Costs And Benefits, Ted von Hippel, Courtney von Hippel 2019 Embry-Riddle Aeronautical University

To Apply Or Not To Apply: A Survey Analysis Of Grant Writing Costs And Benefits, Ted Von Hippel, Courtney Von Hippel

Ted von Hippel

We surveyed 113 astronomers and 82 psychologists active in applying for federally funded research on their grant-­‐writing history between January, 2009 and November, 2012. We collected demographic data, effort levels, success rates, and perceived non-­‐financial benefits from writing grant proposals. We find that the average proposal takes 116 PI hours and 55 CI hours to write; although time spent writing was not related to whether the grant was funded. Effort did translate into success, however, as academics who wrote more grants received more funding. Participants indicated modest non-­‐monetary benefits from grant writing, with psychologists reporting a somewhat ...


Hyper Wide Field Imaging Of The Local Group Dwarf Irregular Galaxy Ic 1613: An Extended Component Of Metal-Poor Stars, Ragadeepika Pucha, Jeffrey L. Carlin, Beth Willman, Jay Strader, David J. Sand, Keith Bechtol, Jean P. Brodie, Denija Crnojević, Duncan A. Forbes, Christopher Garling, Jonathan Hargis, Annika H.G. Peter, Aaron J. Romanowsky 2019 University of Arizona

Hyper Wide Field Imaging Of The Local Group Dwarf Irregular Galaxy Ic 1613: An Extended Component Of Metal-Poor Stars, Ragadeepika Pucha, Jeffrey L. Carlin, Beth Willman, Jay Strader, David J. Sand, Keith Bechtol, Jean P. Brodie, Denija Crnojević, Duncan A. Forbes, Christopher Garling, Jonathan Hargis, Annika H.G. Peter, Aaron J. Romanowsky

Aaron J. Romanowsky

Stellar halos offer fossil evidence for hierarchical structure formation. Since halo assembly is predicted to be scale-free, stellar halos around low-mass galaxies constrain properties such as star formation in the accreted subhalos and the formation of dwarf galaxies. However, few observational searches for stellar halos in dwarfs exist. Here we present gi photometry of resolved stars in isolated Local Group dwarf irregular galaxy IC 1613 (M sstarf ~ 108 M ⊙). These Subaru/Hyper Suprime-Cam observations are the widest and deepest of IC 1613 to date. We measure surface density profiles of young main-sequence, intermediate to old red giant branch, and ancient ...


Spatially Resolved Stellar Kinematics Of The Ultra-Diffuse Galaxy Dragonfly 44. I. Observations, Kinematics, And Cold Dark Matter Halo Fits, Pieter van Dokkum, Asher Wasserman, Shany Danieli, Roberto Abraham, Jean Brodie, Charlie Conroy, Duncan A. Forbes, Christopher Martin, Matt Matuszewski, Aaron J. Romanowsky, Alexa Villaume 2019 Yale University

Spatially Resolved Stellar Kinematics Of The Ultra-Diffuse Galaxy Dragonfly 44. I. Observations, Kinematics, And Cold Dark Matter Halo Fits, Pieter Van Dokkum, Asher Wasserman, Shany Danieli, Roberto Abraham, Jean Brodie, Charlie Conroy, Duncan A. Forbes, Christopher Martin, Matt Matuszewski, Aaron J. Romanowsky, Alexa Villaume

Aaron J. Romanowsky

We present spatially resolved stellar kinematics of the well-studied ultra-diffuse galaxy (UDG) Dragonfly 44, as determined from 25.3 hr of observations with the Keck Cosmic Web Imager. The luminosity-weighted dispersion within the half-light radius is ${\sigma }_{1/2}={33}_{-3}^{+3}$ km s−1, lower than what we had inferred before from a DEIMOS spectrum in the Hα region. There is no evidence for rotation, with ${V}_{\max }/\langle \sigma \rangle \lt 0.12$ (90% confidence) along the major axis, in possible conflict with models where UDGs are the high-spin tail of the normal dwarf galaxy ...


Brightest Cluster Galaxy Evolution Exploration: Comparing The Separation Of Cluster X-Ray Light And Visible Wavelength Galaxy Light With Spectral Data, Matthew Aaron Salinas 2019 California Polytechnic State University, San Luis Obispo

Brightest Cluster Galaxy Evolution Exploration: Comparing The Separation Of Cluster X-Ray Light And Visible Wavelength Galaxy Light With Spectral Data, Matthew Aaron Salinas

Physics

Brightest Cluster Galaxies (BCGs), the brightest galaxy in a cluster of hundreds to thousands of galaxies, are some of the biggest, brightest, and most massive galaxies in the universe. Characterizing a BCG can help discover more about galaxy evolution - the aging, changing, and possible merging (collisions) of galaxies. This project involves determining the separation of the peak of x-ray emission of the galaxy cluster, and the peak of visible emission of the BCG to characterize the system as being disturbed or undisturbed that can then lead to discoveries about its formation and evolution. We have found that 17.4% of ...


Spatially Resolved Stellar Populations And Kinematics With Kcwi: Probing The Assembly History Of The Massive Early-Type Galaxy Ngc 1407, Anna Ferré-Mateu, Duncan A. Forbes, Richard M. McDermid, Aaron J. Romanowsky, Jean P. Brodie 2019 Universitat de Barcelona

Spatially Resolved Stellar Populations And Kinematics With Kcwi: Probing The Assembly History Of The Massive Early-Type Galaxy Ngc 1407, Anna Ferré-Mateu, Duncan A. Forbes, Richard M. Mcdermid, Aaron J. Romanowsky, Jean P. Brodie

Aaron J. Romanowsky

Using the newly commissioned Keck Cosmic Web Imager (KCWI) instrument on the Keck II telescope, we analyze the stellar kinematics and stellar populations of the well-studied massive early-type galaxy (ETG) NGC 1407. We obtained high signal-to-noise integral field spectra for a central and an outer (around one effective radius toward the southeast direction) pointing with integration times of just 600 s and 2400 s, respectively. We confirm the presence of a kinematically distinct core also revealed by VLT/MUSE data of the central regions. While NGC 1407 was previously found to have stellar populations characteristic of massive ETGs (with radially ...


Figure 8: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 8: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 3: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 3: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 5: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 5: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 9: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 9: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 2: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 2: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 10: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 10: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


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