Search Publications
Kinematics of T Tauri Stars Close to the Sun from the Gaia DR2 Catalogue
Bobylev, V. V.
The spatial and kinematic properties of a large sample of young T Tauri stars from the solar neighborhood 500 pc in radius have been studied. The following parameters of the position ellipsoid have been determined from the most probable members of the Gould Belt: its sizes are $350× 270× 87$ pc and it is oriented at an angle of $14^{\circ}± 1^{\ci…
Testing Comptonization as the Origin of the Continuum in Nonmagnetic Cataclysmic Variables: The Photon Index of X-Ray Emission
Maiolino, T.; Titarchuk, L.; Wang, W. +4 more
The X-ray spectra of nonmagnetic cataclysmic variables (nmCVs) in the ∼0.3-15 keV energy band have been described by either one or several optically thin thermal plasma components or by cooling flow models. We tested whether the spectral continuum in nmCVs could be successfully described by Comptonization of soft photons off hot electrons presente…
Identifying the 3FHL Catalog. IV. Swift Observations of Unassociated Fermi-LAT 3FHL Sources
Ajello, M.; Marchesi, S.; Kaur, A. +3 more
The Fermi Large Area Telescope (Fermi-LAT) 3FHL catalog is the latest catalog of >10 GeV sources and will remain an important resource for the high-energy community for the foreseeable future. Therefore, it is crucial that this catalog is made complete by providing associations for most sources. In this paper, we present the results of the X-ra…
Hubble Space Telescope Astrometry of the Metal-poor Visual Binary µ Cassiopeiae: Dynamical Masses, Helium Content, and Age
Schaefer, Gail H.; Bond, Howard E.; Gilliland, Ronald L. +1 more
µ Cassiopeiae is a nearby, high-velocity, metal-poor ([Fe/H] = -0.81) visual binary. We have used high-resolution imaging with the Hubble Space Telescope (HST), obtained over nearly two decades, to determine the period (21.568 yr) and precise orbital elements. Combining these with published ground- and space-based astrometry, we determined d…
Simultaneous Observation of Negatively and Positively Charged Nanograins at Comet 67P/Churyumov-Gerasimenko
Goldstein, R.; Goetz, Charlotte; LLera, K. +1 more
Observations near comet 67P by Rosetta show evidence of charged nanograins. Specifically, the ion and electron sensor (IES) observed negative particles with energy/charge (E/q) consistent with charged nanograins. However, theory predicts that both polarities should be present. On 19 September 2014, IES detected positively and negatively charged pa…
The GRAVITY young stellar object survey. III. The dusty disk of RY Lup
Genzel, R.; Sturm, E.; Ménard, F. +55 more
Context. Studies of the dust distribution, composition, and evolution of protoplanetary disks provide clues for understanding planet formation. However, little is known about the innermost regions of disks where telluric planets are expected to form.
Aims: We aim constrain the geometry of the inner disk of the T Tauri star RY Lup by combining…
Detection of tidal tails around the open cluster M 67 using principal component analysis
Gao, Xinhua
In this paper we present an investigation of tidal tails around the old open cluster M 67 using Gaia-DR2. We identify likely extra-tidal stars around M 67 using principal component analysis (PCA) and a Gaussian mixture model (GMM). We find 1618 stars closely related to M 67, 85 of which are likely extra-tidal stars. We find clear evidence for the …
Is Fornax 4 the nuclear star cluster of the Fornax dwarf spheroidal galaxy?
Martocchia, S.; Dalessandro, E.; Salaris, M. +2 more
Fornax 4 is the most distinctive globular cluster in the Fornax dwarf spheroidal. Located close to the centre of the galaxy, more metal-rich and potentially younger than its four companions (namely, Fornax clusters number 1, 2, 3, and 5), it has been suggested to have experienced a different formation than the other clusters in the galaxy. Here, w…
Searching the Entirety of Kepler Data. I. 17 New Planet Candidates Including One Habitable Zone World
Kunimoto, Michelle; Ngo, Henry; Matthews, Jaymie M.
We present the results of an independent search of all ∼200,000 stars observed over the four year Kepler mission (Q1-Q17) for multiplanet systems, using a three-transit minimum detection criterion to search orbital periods up to hundreds of days. We incorporate both automated and manual triage, and provide estimates of the completeness and reliabi…
Spatiotemporal evolution, mineralogical composition, and transport mechanisms of long-runout landslides in Valles Marineris, Mars
Ehlmann, Bethany L.; Yin, An; Watkins, Jessica A.
Long-runout landslides with transport distances of >50 km are ubiquitous in Valles Marineris (VM), yet the transport mechanisms remain poorly understood. Four decades of studies reveal significant variation in landslide morphology and emplacement age, but how these variations are related to landslide transport mechanisms is not clear. In this s…