Search Publications
How stars formed in warps settle into (and contaminate) thick discs
Debattista, Victor P.; Beraldo e Silva, Leandro; Khachaturyants, Tigran
In recent years star formation has been discovered in the Milky Way's warp. These stars formed in the warp (warp stars) must eventually settle into the plane of the disc. We use an N-body+smooth particle hydrodynamics model of a warped galaxy to study how warp stars settle into the disc. By following warp stars in angular momentum space, we show t…
Precise radial velocities of giant stars. XV. Mysterious nearly periodic radial velocity variations in the eccentric binary ε Cygni
Trifonov, Trifon; Reffert, Sabine; Lee, Man Hoi +10 more
Context. Using the Hamilton Échelle Spectrograph at Lick Observatory, we have obtained precise radial velocities (RVs) of a sample of 373 G- and K-giant stars over more than 12 yr, leading to the discovery of several single and multiple planetary systems. The RVs of the long-period (~53 yr) spectroscopic binary ε Cyg (HIP 102488) are found to exhi…
Exploring the dust content of galactic haloes with Herschel - IV. NGC 3079
Sturm, E.; Veilleux, S.; Rupke, D. S. N. +11 more
We present the results from an analysis of deep Herschel far-infrared (far-IR) observations of the edge-on disc galaxy NGC 3079. The point spread function-cleaned Photodetector Array Camera and Spectrometer (PACS) images at 100 and 160 µm display a 25 × 25 kpc2 X-shape structure centred on the nucleus that is similar in extent and orien…
Jupiter's Double-Arc Aurora as a Signature of Magnetic Reconnection: Simultaneous Observations From HST and Juno
Wei, Y.; Bonfond, B.; Vogt, M. F. +10 more
Jupiter's powerful auroral emission is usually divided into the polar, main, and equatorward components. The driver of Jupiter's main aurora is a central question for the community. Previous investigations reveal many distinct substructures on the main auroral oval, which are indicators of fundamentally different magnetospheric processes. Understa…
The awakening beast in the Seyfert 1 Galaxy KUG 1141+371 - I
Ho, Luis C.; Steiner, James F.; Fabian, Andrew C. +10 more
KUG 1141+371 is a Seyfert 1 galaxy that shows a simultaneous flux increase in the optical and UV bands in the past decade. For instance, the latest Swift observation in 2019 shows that the UVW2 flux of the active galactic nucleus in KUG 1141+371 has increased by over one order of magnitude since 2009. Meanwhile, the soft X-ray flux of KUG 1141+371…
H2 molecular gas absorption-selected systems trace CO molecular gas-rich galaxy overdensities
Lopez, Sebastian; Péroux, Céline; De Cia, Annalisa +3 more
Absorption-selected galaxies offer an effective way to study low-mass galaxies at high redshift. However, the physical properties of the underlying galaxy population remain uncertain. In particular, the multiphase circumgalactic medium is thought to hold key information on gas flows into and out of galaxies that are vital for galaxy evolution mode…
Observation of solar coronal heating powered by magneto-acoustic oscillations in a moss region
Ji, Kai-Fan; Hashim, Parida; Hong, Zhen-Xiang +3 more
In this paper, we report the observed temporal correlation between extreme-ultraviolet (EUV) emission and magneto-acoustic oscillations in an EUV moss region, which is the footpoint region only connected by magnetic loops with million-degree plasma. The result is obtained from a detailed multi-wavelength data analysis of the region with the purpos…
Measuring Young Stars in Space and Time. II. The Pre-main-sequence Stellar Content of N44
Gennaro, Mario; Dolphin, Andrew E.; Klessen, Ralf S. +9 more
The Hubble Space Telescope survey Measuring Young Stars in Space and Time (MYSST) entails some of the deepest photometric observations of extragalactic star formation, capturing even the lowest-mass stars of the active star-forming complex N44 in the Large Magellanic Cloud. We employ the new MYSST stellar catalog to identify and characterize the c…
Io's SO2 atmosphere from HST Lyman-α images: 1997 to 2018
Giono, Gabriel; Roth, Lorenz
The atmosphere of Jupiter's volcanic moon Io consists of mainly sulfur dioxide (SO2), and this main constituent has been studied with a variety of observing techniques across many wavelengths over the years. Here we study absorption by SO2 at the hydrogen Ly-α line (1216 Å) in a large set of images taken by the Space Telescop…
The infrared excess emission from nearby Gaia DR2 M dwarfs
Song, Inseok; Sgro, Lauren A.
We use Gaia DR2 data to search for M dwarfs with infrared (IR) excess, within 100 pc. By cross-matching Gaia with AllWISE and 2MASS catalogues, we select a subset of K/M dwarfs with reliable photometric data in both the optical and near-to-mid IR. Using our SED fitting pipeline, we determine a photospheric model for each star and determine its sig…