Search Publications
Velocity-inverted Three-dimensional Distribution of the Gas Clouds in the Type 2 AGN NGC 1068
Kishimoto, Makoto; Miyauchi, Ryuji
Spatially resolved velocity maps at high resolutions of 1-10 pc are becoming available for many nearby active galactic nuclei (AGNs) in both optical/infrared atomic emission lines and submillimeter molecular lines. For the former, it is known that a linear relationship appears to exist between the velocity of the ionized gas clouds and the distanc…
Two Substructures in the nearby Stellar Halo Found in Gaia and RAVE
Shi, Jianrong; Ma, Jun; Du, Cuihua +4 more
We use the second Gaia data release (Gaia DR2), combined with Radial Velocity Experiment spectroscopic surveys, to identify the substructures in the nearby stellar halo. We select 3845 halo stars kinematically and chemically and determine their density distribution in energy and angular momentum space. To select the substructures from overdensitie…
Axial Asymmetry Studies in Gaia Data Release 2 Yield the Pattern Speed of the Galactic Bar
Yanny, Brian; Gardner, Susan; Hinkel, Austin
Our recent studies of axial-symmetry breaking in the nearby (d < 3 kpc) star counts are sensitive to the distortions of stellar orbits perpendicular and parallel to the orientation of the bar just within and beyond the outer Lindblad resonance (OLR) radius. Using the location of the sign flip in the left-right asymmetry in stars counts about th…
The Kinematic Evolution of Erupting Structures in Confined Solar Flares
Cheng, X.; Ding, M. D.; Huang, Z. W.
In this Letter, we study the kinematic properties of ascending hot blobs associated with confined flares. Taking advantage of high-cadence extreme-ultraviolet images provided by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, we find that for the 26 events selected here, the hot blobs are first impulsively accelerated out…
X-Ray Constraints on the Spectral Energy Distribution of the z = 5.18 Blazar SDSS J013127.34-032100.1
An, Hongjun; Romani, Roger W.
We report on X-ray measurements constraining the spectral energy distribution (SED) of the high-redshift z = 5.18 blazar SDSS J013127.34-032100.1 with new XMM-Newton and NuSTAR exposures. The blazar's X-ray spectrum is well fit by a power law with Γ = 1.9 and ${N}_{{\rm{H}}}=1.1\times {10}^{21}\,{\mathrm{cm}}^{-2}$ , or a broken power law with ${{…
Infrared Color Separation between Thin-shelled Oxygen-rich and Carbon-rich AGB Stars
Sjouwerman, Loránt O.; Pihlström, Ylva M.; Lewis, Megan O. +1 more
We present 43 GHz VLA spectra for 51 AGB sources with the goal of verifying an infrared (IR) color cut intended to separate carbon-rich (C) and oxygen-rich (O) AGB sources throughout the Galaxy. The color cut is a simple line in the [Ks] - [A] versus [A] - [E] color-color diagram based on 2MASS and MSX photometry, and was originally der…
Distinct Accretion Modes of Cygnus X-1 Revealed from Hard X-Rays
Zdziarski, Andrzej A.; Lubiński, Piotr; Pooley, Guy +1 more
Thanks to recurrent observations of the black hole binary Cyg X-1 carried out over 15 years the INTEGRAL satellite has collected the largest data set in the hard X-ray band for this source. We have analyzed these data, complemented by data collected by other X-ray satellites and radio flux at 15 GHz. To characterize the spectral and variability pr…
An Extremely Bright QSO at z = 2.89
Stern, Daniel; Gonzalez, Anthony; Ackley, Kendall +4 more
We report the discovery and confirmation of a bright quasi-stellar object (QSO), 2MASS J13260399 + 7023462, at $z=2.889$ . This QSO is the first spectroscopically confirmed candidate from an ongoing search using the combination of Gaia and Wide-field Infrared Survey Explorer photometry to identify bright QSOs at z > 2, the redshift regime for w…
Anomalous Extinction toward NGC 1938
Milone, Antonino P.; Panagia, Nino; De Marchi, Guido
Intrigued by the extended red giant clump (RC) stretching across the color-magnitude diagram of the stars in a 50 × 50 pc2 region of the Large Magellanic Cloud (LMC) containing the clusters NGC 1938 and NGC 1939, we have studied the stellar populations to learn about the properties of the interstellar medium (ISM) in this area. The exte…
Prediction of the Sun's Coronal Magnetic Field and Forward-modeled Polarization Characteristics for the 2019 July 2 Total Solar Eclipse
Nandy, Dibyendu; Dash, Soumyaranjan; Bhowmik, Prantika +2 more
On 2019 July 2 a total solar eclipse—visible across parts of the Southern Pacific Ocean, Chile, and Argentina—enabled observations of the Sun's corona. The structure and emission characteristics of the corona are determined by underlying magnetic fields, which also govern coronal heating and solar eruptive events. However, coronal magnetic field m…