A5018962311- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Astrophysics and Star Formation Studies
- Distributed and Parallel Computing Systems
- Astrophysical Phenomena and Observations
- Solar and Space Plasma Dynamics
- Dark Matter and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Cosmic Phenomena
- X-ray Spectroscopy and Fluorescence Analysis
- History and Developments in Astronomy
- Cultural Heritage Materials Analysis
- Geomagnetism and Paleomagnetism Studies
Georgia State University
2020-2024
Vanderbilt University
2023-2024
Ames Research Center
2019
The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is first one for SDSS-V, fifth generation survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole (BHM), and Local Volume (LVM). This contains extensive targeting information two multi-object spectroscopy programs (MWM BHM), including input catalogs selection functions their numerous objectives. We describe production databases calibration- scientifically-focused...
The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is first one for SDSS-V, fifth generation survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole (BHM), and Local Volume (LVM). This contains extensive targeting information two multi-object spectroscopy programs (MWM BHM), including input catalogs selection functions their numerous objectives. We describe production databases calibration- scientifically-focused...
Abstract Optical and infrared continuum polarization from the interstellar medium is known to generally be due irregular dust grains aligned with magnetic field. This provides an important tool probe geometry strength of those fields, particularly if variations in grain alignment efficiencies can understood. Here, we examine observed throughout wall Local Bubble, using a large survey North Galactic cap ( b > 30°) Berdyugin et al. These data are analyzed together archival photometric...
Abstract Dust-induced polarization in the interstellar medium (ISM) is due to asymmetric grains aligned with an external reference direction, usually magnetic field. For both leading alignment theories, of grain’s angular momentum one its principal axes and coupling field requires grain be paramagnetic. Of two main components dust, silicates are paramagnetic, while carbon dust diamagnetic. Hence, not expected align ISM. To probe physics alignment, we have acquired Stratospheric Observatory...
Abstract We present a method to identify likely visual binaries in Gaia eDR3 that does not rely on parallax or proper motion. This utilizes the various point-spread function sizes of Two Micron All Sky Survey (2MASS)/Gaia, where at <2.″5 two stars may be unresolved 2MASS but resolved by Gaia. Due this, if close neighbors listed are pair, associated source will have predictable excess J band depends Δ G pair. demonstrate expected relationship between and differs for chance alignments, as...
We combine photometric metallicities with astrometry from Gaia DR3 to examine the chemodynamic structure of ~250,000 K dwarfs in Solar Neighborhood (SN). In kinematics, we observe ridges/clumps "kinematic groups", like studies more massive main-sequence stars. Here note clear differences both metallicity and vertical velocity as compared surrounding regions space hypothesize this is due mean age. To test this, develop a method estimate age distribution sub-populations method, use GALAH data...
We present a Bayesian method to cross-match 5,827,988 high proper motion Gaia sources ($\mu>40 \ mas yr^{-1}$) various photometric surveys: 2MASS, AllWISE, GALEX, RAVE, SDSS and Pan-STARRS. To efficiently associate these objects across catalogs, we develop technique that compares the multidimensional distribution of all in vicinity each star reference random field stars obtained by extracting region on sky displaced 2$^\prime$. This offset preserves local stellar density magnitude allowing...
Abstract Over the past decade, number of known wide-binary systems has expanded exponentially, thanks to release data from Gaia Mission. Some these are actually higher-order multiples, where one components is an unresolved binary itself. One way search for by identifying overluminous in systems. In this study, we examine 4947 K+K pairs SUPERWIDE catalog, and quantify relative colors luminosities find evidence additional companions. The method best illustrated a graph that call “Lobster”...
We present a catalog of 531 white dwarf candidates that have large apparent transverse motions relative to the Sun ( km s−1), thus making them likely members local Galactic halo population. The were selected from Gaia Data Release 2 and are located in great circle with 20° width running across both poles center anticenter, zone spans 17.3% sky. selection used combination kinematic photometric properties, derived primarily proper motions, G magnitudes, color, including parallax whenever...
Here we present speckle observations of 16 low-separation ($s<30$ AU) high probability candidate binaries from the catalog by Medan et al., where secondaries typically lack astrometric solutions in Gaia. From these observations, find a second component is always detected within field view. To determine if detection consistent with physical companion or chance alignment background source, utilize statistic Tokovinin & Kiyaeva that compares apparent motion systems to expected orbital...
Abstract Here we present speckle observations of 16 low-separation ( s < 30 au) high-probability candidate binaries from the catalog by Medan et al., where secondaries typically lack astrometric solutions in Gaia. From these observations, find a second component is always detected within field view. To determine if detection consistent with physical companion or chance alignment background source, utilize statistic Tokovinin & Kiyaeva that compares apparent motion systems to expected...
The Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) dataset will dramatically alter our understanding the Universe, from origins Solar System to nature dark matter energy. Much this research depend on existence robust, tested, scalable algorithms, software, services. Identifying developing such tools ahead time has potential significantly accelerate delivery early science LSST. Developing these collaboratively, making them broadly available, can enable more inclusive...
We present a method to identify likely visual binaries in Gaia eDR3 that does not rely on parallax or proper motion. This utilizes the various PSF sizes of 2MASS/Gaia, where at $<2.5$" two stars may be unresolved 2MASS but resolved by Gaia. Due this, if close neighbors listed are pair, associated source will have predictable excess J-band depends $\Delta G$ pair. demonstrate expected relationship between and differs for chance alignments, as compared true binary systems, when parameters like...
We combine photometric metallicities with astrometry from Gaia DR3 to examine the chemodynamic structure of ~250,000 K dwarfs in Solar Neighborhood (SN). In kinematics, we observe ridges/clumps "kinematic groups", like studies more massive main-sequence stars. Here note clear differences both metallicity and vertical velocity as compared surrounding regions space hypothesize this is due mean age. To test this, develop a method estimate age distribution sub-populations method, use GALAH data...