Search Publications
Astrometric Exoplanet Detection with Gaia
Bakos, Gáspár Á.; Lindegren, Lennart; Hartman, Joel +1 more
We provide a revised assessment of the number of exoplanets that should be discovered by Gaia astrometry, extending previous studies to a broader range of spectral types, distances, and magnitudes. Our assessment is based on a large representative sample of host stars from the TRILEGAL Galaxy population synthesis model, recent estimates of the exo…
Predicted Space Motions for Hypervelocity and Runaway Stars: Proper Motions and Radial Velocities for the Gaia Era
Geller, Margaret J.; Brown, Warren R.; Kenyon, Scott J. +1 more
We predict the distinctive three-dimensional space motions of hypervelocity stars (HVSs) and runaway stars moving in a realistic Galactic potential. For nearby stars with distances less than 10 kpc, unbound stars are rare; proper motions alone rarely isolate bound HVSs and runaways from indigenous halo stars. At large distances of 20-100 kpc, unbo…
The Variable Sky of Deep Synoptic Surveys
Matheson, Thomas; Howell, Steve B.; Mighell, Kenneth J. +2 more
The discovery of variable and transient sources is an essential product of synoptic surveys. The alert stream will require filtering for personalized criteria—a process managed by a functionality commonly described as a Broker. In order to understand quantitatively the magnitude of the alert generation and Broker tasks, we have undertaken an analy…
Microlensing Events by Proxima Centauri in 2014 and 2016: Opportunities for Mass Determination and Possible Planet Detection
Anderson, Jay; Bond, Howard E.; Sahu, Kailash C. +1 more
We have found that Proxima Centauri, the star closest to our Sun, will pass close to a pair of faint background stars in the next few years. Using Hubble Space Telescope (HST) images obtained in 2012 October, we determine that the passage close to a mag 20 star will occur in 2014 October (impact parameter 1.''6), and to a mag 19.5 star in 2016 Feb…
The Gaia Inertial Reference Frame and the Tilting of the Milky Way Disk
Spergel, David N.; Lindegren, Lennart; Perryman, Michael
While the precise relationship between the Milky Way disk and the symmetry planes of the dark matter halo remains somewhat uncertain, a time-varying disk orientation with respect to an inertial reference frame seems probable. Hierarchical structure formation models predict that the dark matter halo is triaxial and tumbles with a characteristic rat…