Search Publications
Polarization Characteristics of Zebra Patterns in Type IV Solar Radio Bursts
Misawa, H.; Masuda, S.; Tsuchiya, F. +4 more
The polarization characteristics of zebra patterns (ZPs) in type IV solar bursts were studied. We analyzed 21 ZP events observed by the Assembly of Metric-band Aperture Telescope and Real-time Analysis System between 2010 and 2015 and identified the following characteristics: a degree of circular polarization (DCP) in the range of 0%-70%, a tempor…
Observation of a Large-scale Quasi-circular Secondary Ribbon Associated with Successive Flares and a Halo CME
Yurchyshyn, Vasyl; Chae, Jongchul; Cho, Kyuhyoun +7 more
Solar flare ribbons provide an important clue to the magnetic reconnection process and associated magnetic field topology in the solar corona. We detected a large-scale secondary flare ribbon of a circular shape that developed in association with two successive M-class flares and one coronal mass ejection. The ribbon revealed interesting propertie…
A New 3D Multi-fluid Dust Model: A Study of the Effects of Activity and Nucleus Rotation on Dust Grain Behavior at Comet 67P/Churyumov-Gerasimenko
Huang, Z.; Jia, X.; Fougere, N. +7 more
Improving our capability to interpret observations of cometary dust is necessary to deepen our understanding of the role of dust in the formation of comets and in altering the cometary environments. Models including dust grains are in demand to interpret observations and test hypotheses. Several existing models have taken into account the gas-dust…
Photospheric Velocity Structures during the Emergence of Small Active Regions on the Sun
Toriumi, Shin; Khlystova, Anna
We study the plasma flows in the solar photosphere during the emergence of two small active regions, NOAA 9021 and 10768. Using Solar and Heliospheric Observatory/Michelson Doppler Imager data, we find that the strong plasma upflows appear at the initial stage of active region formation, with maximum upflow velocities of -1650 and -1320 m s-1…
The Spiral Arm Segments of the Galaxy within 3 kpc from the Sun: A Statistical Approach
Hou, Li-Gang; Jiang, Ing-Guey; Griv, Evgeny
As can be reasonably expected, upcoming large-scale APOGEE, GAIA, GALAH, LAMOST, and WEAVE stellar spectroscopic surveys will yield rather noisy Galactic distributions of stars. In view of the possibility of employing these surveys, our aim is to present a statistical method to extract information about the spiral structure of the Galaxy from curr…
The Circumgalactic Medium of Submillimeter Galaxies. II. Unobscured QSOs within Dusty Starbursts and QSO Sightlines with Impact Parameters below 100 kpc
Casey, Caitlin M.; Prochaska, J. Xavier; Scoville, Nick +4 more
We present Atacama Large Millimeter/submillimeter Array (ALMA) 870 µm observations of 29 bright Herschel sources near high-redshift QSOs. The observations confirm that 20 of the Herschel sources are submillimeter-bright galaxies (SMGs) and identify 16 new SMG-QSO pairs that are useful to studies of the circumgalactic medium (CGM) of SMGs. Ei…
An XMM-Newton Study of the Mixed-morphology Supernova Remnant G346.6-0.2
Auchettl, Katie; Slane, Patrick; Ng, C. -Y. +2 more
We present an X-ray imaging and spectroscopic study of the molecular cloud interacting mixed-morphology supernova remnant G346.6-0.2 using XMM-Newton. The X-ray spectrum of the remnant is well described by a recombining plasma that most likely arises from adiabatic cooling and has subsolar abundances of Mg, Si, and S. Our fits also suggest the pre…
Optical Properties of Non-stoichiometric Amorphous Silicates with Application to Circumstellar Dust Extinction
Tamanai, Akemi; Pucci, Annemarie; Dohmen, Ralf +1 more
We determine the optical constants of non-stoichiometric amorphous magnesium-iron silicates and demonstrate that they can well reproduce the observed mid-infrared emission spectra of evolved stars. Stoichiometric and non-stoichiometric amorphous magnesium-iron silicate films are fabricated by pulsed laser deposition. Transmittance and ellipsometry…
Sparse Bayesian Inference and the Temperature Structure of the Solar Corona
Warren, Harry P.; Byers, Jeff M.; Crump, Nicholas A.
Measuring the temperature structure of the solar atmosphere is critical to understanding how it is heated to high temperatures. Unfortunately, the temperature of the upper atmosphere cannot be observed directly, but must be inferred from spectrally resolved observations of individual emission lines that span a wide range of temperatures. Such obse…
Double Stars and Astrometric Uncertainties in Gaia DR1
Makarov, Valeri V.; Frouard, Julien; Fabricius, Claus
A significant number of double stars with separations up to 2.5 arcsec are present in the Gaia Data Release 1 astrometric catalogs. Limiting our analysis to a well-studied sample of 1124 doubles resolved by Hipparcos, provided with individual Tycho component photometry and cross-matched with the TGAS catalog, we estimate a rate of at least 3% for …