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Extreme X-Ray Reflection in the Nucleus of the Seyfert Galaxy NGC 5033
Stern, D.; Brandt, W. N.; Fabian, A. C. +7 more
NGC 5033 is an intriguing Seyfert galaxy because its subclassification may change with time, and because optical and submillimeter observations find that the massive black hole does not sit at the dynamical center of the galaxy, pointing to a past merger. We obtained a new optical spectrum of NGC 5033 using the 200″ Hale telescope at Palomar that …
Milliarcsecond X-Ray Astrometry to Resolve Inner Regions of AGN at z > 1 Using Gravitational Lensing
Barnacka, Anna; Spingola, Cristiana; Schwartz, Daniel
We report the localization of the X-ray emission from two strongly lensed AGN, CLASS B0712+472 (z = 1.34) and CLASS B1608+656 (z = 1.394). We obtain milliarcsecond X-ray astrometry by developing a novel method that combines parametric lens modeling with a Bayesian analysis. We spatially locate the X-ray sources in CLASS B0712+472 and CLASS B1608+6…
FAST Search for Circumstellar Atomic Hydrogen. I. The Young Planetary Nebula IC 4997
Zhang, Yong; Zhang, Chuan-Peng; Parker, Quentin A. +3 more
Using the Five-hundred-meter Aperture Spherical radio Telescope in Guizhou, China, we detect the 21 cm neutral atomic hydrogen absorption in the young planetary nebula IC 4997. The absorption arises from a shell that is also associated with Na I D lines. The H I shell has a mass of 1.46 × 10-2 M ⊙ and a dynamic age of 990 yr.…
Extreme Solar Flare-driven Short-wave Fadeout Observed by SuperDARN ZHO Radar
Wang, M.; Liu, J.; Lu, J. Y. +6 more
Based on the observations from the Super Dual Auroral Radar Network at the Zhongshan Station (-74.9 MLAT, 97.2 MLON) and GOES satellites X-ray sensor, we present the first statistical study of the dayside ionospheric short-wave fadeout (SWF) events on the Southern Hemispheric high latitude from the years 2010-2019 and provide a normal characterist…
Erratum: Primordial black hole origin for thermal gamma-ray bursts
del Barco, Oscar
A 2+1 + 1 quadruple star system containing the most eccentric, low-mass, short-period, eclipsing binary known
Vanderburg, A.; Zasche, P.; Borkovits, T. +12 more
We present an analysis of a newly discovered 2+1 + 1 quadruple system with TESS containing an unresolved eclipsing binary (EB) as part of TIC 121088960 and a close neighbour TIC 121088959. The EB consists of two very low-mass M dwarfs in a highly eccentric (e = 0.709) short-period (P = 3.043 58 d) orbit. Given the large pixel size of TESS and the …
Spectroscopic Diagnostics of the Mid-infrared Features of the Dark Globule DC 314.8-5.1 with the Spitzer Space Telescope
Stawarz, Ł.; Rocha, W. R. M.; Kosmaczewski, E. +2 more
We present an analysis of the mid-infrared spectra, obtained from the Spitzer Space Telescope, of the dark globule DC 314.8-5.1, which is at the onset of low-mass star formation. The target has a serendipitous association with a B-type field star that illuminates a reflection nebula in the cloud. We focus on the polycyclic aromatic hydrocarbon (PA…
The spiral density-wave structure of the Milky Way in the 3-kpc-scale solar neighbourhood: line-of-sight velocities of 252 young open clusters
Gedalin, Michael; Jiang, Ing-Guey; Griv, Evgeny
Following Lin and Shu, the spiral structure in the Milky Way disc is considered as an oscillating density-wave pattern. As such, regular enhancements in density are relatedly linked to systematic variations in velocity of young stars and stellar clusters, and interstellar gas. We explain measured line-of-sight velocities of 252 open clusters with …
TIC 5724661: A Long-period Binary with a Pulsating sdB Star and δ Scuti Variable
Rappaport, Saul A.; Jayaraman, Rahul; Bieryla, Allyson +8 more
Using TESS 20 s cadence data, we have discovered an unusual combination of pulsating stars in what we infer to be a binary system. The binary consists of a standard δ Scuti star with pulsations over the range 32-41 day-1; this is in a likely wide orbit with a hot subdwarf-B (sdB) star, which itself has a large-amplitude p-mode pulsation…
Plasma vortices driven by magnetic torsion generated by electric currents in non-magnetic planetary wakes
Flandes, Alberto; Durand-Manterola, Héctor Javier
In non-collisional magnetised astrophysical plasmas, vortices can form as it is the case of the Venus plasma wake where Lundin et al. (2013) identified a large vortex through the integration of data of many orbits from the Venus Express (VEX) spacecraft. On the one hand, our purpose is to develop a theoretical foundation in order to explain the oc…