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Swift J0503.7-2819: a Short-period Asynchronous Polar or Stream-fed Intermediate Polar
Halpern, J. P.
We analyze a 7.4 hr XMM-Newton light curve of the cataclysmic variable Swift J0503.7-2819, previously classified using optical periods as an intermediate polar (IP) with an orbital period of 0.0567 days. A photometric signal at 975 s, previously suggested to be the spin period, is not present in X-rays and is readily understood as a quasiperiodic …
The Internal Line-of-Sight Kinematics of NGC 346: The Rotation of the Core Region
Sabbi, Elena; Nota, Antonella; Zeidler, Peter
We present the stellar radial velocity analysis of the central $1^{\prime} \times 1^{\prime} $ of the young massive Small Magellanic Cloud star cluster NGC 346. Using VLT/MUSE integral field spectroscopy in combination with Hubble Space Telescope photometry, we extract 103 spectra of cluster member stars suited to measure accurate line-of-sight ki…
Effect of Differential Rotation on the Magnetic Braking of Low-mass and Solar-like Stars: A Proof-of-concept Study
Finley, Adam J.; Matt, Sean P.; Ireland, Lewis G. +4 more
On the main sequence, low-mass and solar-like stars are observed to spin down over time, and magnetized stellar winds are thought to be predominantly responsible for this significant angular momentum loss. Previous studies have demonstrated that the wind torque can be predicted via formulations dependent on stellar properties, such as magnetic fie…
AstroSat View of Spectral Transition in the Changing-look Active Galaxy NGC 1566 during the Declining Phase of the 2018 Outburst
Dewangan, Gulab C.; Tripathi, Prakash
NGC 1566 is a changing-look active galaxy that exhibited an outburst during 2017-2018 with a peak in 2018 June. We triggered AstroSat observations of NGC 1566 twice in 2018 August and October during its declining phase. Using the AstroSat observations, along with two XMM-Newton observations in 2015 (pre-outburst) and 2018 June (peak outburst), we …
CHANG-ES. XXIV. First Detection of a Radio Nuclear Ring and Potential LLAGN in NGC 5792
Wang, Q. Daniel; Li, Zhiyuan; Sun, Wei +8 more
We report the discoveries of a nuclear ring of diameter 10″ (~1.5 kpc) and a potential low-luminosity active galactic nucleus (LLAGN) in the radio continuum emission map of the edge-on barred spiral galaxy NGC 5792. These discoveries are based on the Continuum Halos in Nearby Galaxies-an Expanded Very Large Array (VLA) Survey, as well as subsequen…
A Selection of Hα Emitters at z = 2.1-2.5 Using the K s -band Photometry of ZFOURGE
Spitler, Lee R.; Motohara, Kentaro; Chen, Nuo +1 more
Large and less-biased samples of star-forming galaxies are essential to investigate galaxy evolution. Hα emission line is one of the most reliable tracers of star-forming galaxies because its strength is directly related to recent star formation. However, it is observationally expensive to construct large samples of Hα emitters by spectroscopic or…
Very Large Telescope MUSE Observations of the Bubble Nebula around NGC 1313 X-2 and Evidence for Additional Photoionization
Feng, Hua; Bian, Fuyan; Zhou, Changxing +1 more
The bubble nebula surrounding NGC 1313 X-2 is believed to be powered by high velocity winds from the central ultraluminous X-ray source (ULX) as a result of supercritical accretion. With the Multi-Unit Spectroscopic Explorer (MUSE) observation of the nebula, we find enhanced [O III] emission at locations spatially coincident with clusters of stars…
Variations of the Plasma Environment Revealed by the Evolution of the Supra-arcade Fan in the 2017 September 10 Flare
Cai, Qiangwei; Ye, Jing; Feng, Hengqiang +1 more
Based on observations from the Interface Region Imaging Spectrograph and Hinode, we analyze the thermodynamic evolution of the supra-arcade fan (SAF) in the 2017 September 10 flare. The SAF presents discontinuous characters during the rising process, indicating a nonuniform process of magnetic reconnection in the solar eruption. The intensity peak…
Accurate Modeling of Lyα Profiles and Their Impact on Photolysis of Terrestrial Planet Atmospheres
Loyd, R. O. Parke; Peacock, Sarah; Schwieterman, Edward W. +4 more
Accurately measuring and modeling the Lyα (Lyα; λ1215.67 Å) emission line from low-mass stars is vital for our ability to build predictive high energy stellar spectra, yet interstellar medium (ISM) absorption of this line typically prevents model-measurement comparisons. Lyα also controls the photodissociation of important molecules, like water an…
A Near-infrared Look at AGN Feedback in Bulgeless Galaxies
Bohn, Thomas; Canalizo, Gabriela; Satyapal, Shobita +1 more
While it is generally believed that supermassive black holes (SMBHs) lie in most galaxies with bulges, few SMBHs have been confirmed in bulgeless galaxies. Identifying such a population could provide important insights to the BH seed population and secular BH growth. To this end, we obtained near-infrared (NIR) spectroscopic observations of a samp…