Search Publications
The GALAH survey and Gaia DR2: Linking ridges, arches, and vertical waves in the kinematics of the Milky Way
Lewis, Geraint F.; Ting, Yuan-Sen; Buder, Sven +17 more
Gaia DR2 has revealed new small-scale and large-scale patterns in the phase-space distribution of stars in the Milky Way. In cylindrical Galactic coordinates (R,φ ,z), ridge-like structures can be seen in the (R,V_φ) plane and asymmetric arch-like structures in the (V_R,V_φ) plane. We show that the ridges are also clearly present when the third di…
The Nearby, Young, Argus Association: Membership, Age, and Dusty Debris Disks
Zuckerman, B.
The reality of a field Argus Association has been doubted in some papers in the literature. We apply Gaia DR2 data to stars previously suggested to be Argus members and conclude that a true association exists with age 40-50 Myr and containing many stars within 100 pc of Earth; β Leo and 49 Cet are two especially interesting members. Based on youth…
Drifting of the line-tied footpoints of CME flux-ropes
Aulanier, Guillaume; Dudík, Jaroslav
Context. Bridging the gap between heliospheric and solar observations of eruptions requires the mapping of interplanetary coronal mass ejection (CME) footpoints down to the Sun's surface. But this not straightforward. Improving the understanding of the spatio-temporal evolutions of eruptive flares requires a comprehensive standard model. But the c…
VLT/SPHERE exploration of the young multiplanetary system PDS70
Rouan, D.; Pinte, C.; Henning, T. +51 more
Context. PDS 70 is a young (5.4 Myr), nearby ( 113 pc) star hosting a known transition disk with a large gap. Recent observations with SPHERE and NACO in the near-infrared (NIR) allowed us to detect a planetary mass companion, PDS 70 b, within the disk cavity. Moreover, observations in Hα with MagAO and MUSE revealed emission associated…
Three Red Suns in the Sky: A Transiting, Terrestrial Planet in a Triple M-dwarf System at 6.9 pc
Barclay, Thomas; Latham, David W.; Berlind, Perry +40 more
We present the discovery from Transiting Exoplanet Survey Satellite (TESS) data of LTT 1445Ab. At a distance of 6.9 pc, it is the second nearest transiting exoplanet system found to date, and the closest one known for which the primary is an M dwarf. The host stellar system consists of three mid-to-late M dwarfs in a hierarchical configuration, wh…
A Sequoia in the Garden: FSR 1758—Dwarf Galaxy or Giant Globular Cluster?
Monachesi, Antonela; Gómez, Facundo A.; Minniti, Dante +5 more
We present the physical characterization of FSR 1758, a new large, massive object very recently discovered in the Galactic Bulge. The combination of optical data from the 2nd Gaia Data Release and the DECam Plane Survey and near-IR data from the VISTA Variables in the Vía Láctea Extended Survey led to a clean sample of likely members. Based on thi…
Discovery of a Third Transiting Planet in the Kepler-47 Circumbinary System
Torres, Guillermo; Cochran, William D.; Endl, Michael +16 more
Of the nine confirmed transiting circumbinary planet systems, only Kepler-47 is known to contain more than one planet. Kepler-47 b (the “inner planet”) has an orbital period of 49.5 days and a radius of about 3 R ⊕. Kepler-47 c (the “outer planet”) has an orbital period of 303.2 days and a radius of about 4.7 R ⊕. Here we rep…
The dwarf galaxy satellite system of Centaurus A
Müller, Oliver; Jerjen, Helmut; Lelli, Federico +4 more
Dwarf galaxy satellite systems are essential probes to test models of structure formation, making it necessary to establish a census of dwarf galaxies outside of our own Local Group. We present deep FORS2 VI band images from the ESO Very Large Telescope (VLT) for 15 dwarf galaxy candidates in the Centaurus group of galaxies. We confirm nine dwarfs…
A Survey of C2H, HCN, and C18O in Protoplanetary Disks
Bergin, Edwin A.; Bergner, Jennifer B.; Loomis, Ryan A. +3 more
Molecular lines observed toward protoplanetary disks carry information about physical and chemical processes associated with planet formation. We present ALMA Band 6 observations of C2H, HCN, and C18O in a sample of 14 disks spanning a range of ages, stellar luminosities, and stellar masses. Using C2H and HCN hyper…
Using Herschel and Planck observations to delineate the role of magnetic fields in molecular cloud structure
Soler, Juan D.
We present a study of the relative orientation between the magnetic field projected onto the plane of sky (B⊥) on scales down to 0.4 pc, inferred from the polarized thermal emission of Galactic dust observed by Planck at 353 GHz, and the distribution of gas column density (NH) structures on scales down to 0.026 pc, derived fr…