Search Publications
Statistics of Wide Pre-main-sequence Binaries in the Orion OB1 Association
Tokovinin, Andrei; Petr-Gotzens, Monika G.; Briceño, Cesar
Statistics of low-mass pre-main-sequence binaries in the Orion OB1 association with separations ranging from 0"6 to 20″ (220 to 7400 au at 370 pc) are studied using images from the VISTA Orion mini survey and astrometry from Gaia. The input sample based on the CVSO catalog contains 1137 stars of K and M spectral types (masses between 0.3 and 0.9 $…
Multiple Explanations for the Single Transit of KIC 5951458 Based on Radial Velocity Measurements Extracted with a Novel Matched-template Technique
Kane, Stephen R.; Howard, Andrew W.; Dalba, Paul A. +2 more
Planetary systems that show single-transit events are a critical pathway to increasing the yield of long-period exoplanets from transit surveys. From the primary Kepler mission, KIC 5951458 b (Kepler-456b) was thought to be a single-transit giant planet with an orbital period of 1310 days. However, radial velocity (RV) observations of KIC 5951458 …
On the Metamorphosis of the Bailey Diagram for RR Lyrae Stars
Kovtyukh, V.; Lemasle, B.; Walker, A. R. +37 more
We collected over 6000 high-resolution spectra of four dozen field RR Lyrae (RRL) variables pulsating either in the fundamental (39 RRab) or in the first overtone (9 RRc) mode. We measured radial velocities (RVs) of four strong metallic and four Balmer lines along the entire pulsational cycle and derived RV amplitudes with accuracies better than 1…
Revisiting the Magnetic Field of the L183 Starless Core
Karoly, Janik; Bastien, Pierre; Coudé, Simon +4 more
We present observations of linear polarization from dust thermal emission at 850 µm toward the starless cloud L183. These data were obtained at the James Clerk Maxwell Telescope (JCMT) using the SCUBA-2 camera in conjunction with its polarimeter POL-2. Polarized dust emission traces the plane-of-sky magnetic field structure in the cloud, thu…
The Inner Disk of RY Tau: Evidence of Stellar Occultation by the Disk Atmosphere at the Sublimation Rim from K-band Continuum Interferometry
Monnier, John D.; Kraus, Stefan; Baron, Fabien +13 more
We present models of the inner region of the circumstellar disk of RY Tau that aim to explain our near-infrared (K-band: 2.1 µm) interferometric observations, while remaining consistent with the optical to near-infrared portions of the spectral energy distribution. Our submilliarcsecond-resolution CHARA Array observations are supplemented wi…
Non-stoichiometric amorphous magnesium-iron silicates in circumstellar dust shells. Dust growth in outflows from supergiants
Tamanai, Akemi; Pucci, Annemarie; Dohmen, Ralf +1 more
Aims: We study the growth of dust in oxygen-rich stellar outflows in order to find out to which extent dust growth models can quantitatively reconcile with the quantities and nature of dust as derived from observations of the infrared emission from circumstellar dust shells.
Methods: We use a set of nine well-observed massive supergiants…
Mapping the Galactic Disk with the LAMOST and Gaia Red Clump Sample. IV. The Kinematic Signature of the Galactic Warp
Wang, H. -F.; Huang, Y.; Chen, B. -Q. +5 more
Using a sample of nearly 140,000 red clump stars selected from the LAMOST and Gaia Galactic surveys, we have mapped mean vertical velocity $\overline{{V}_{z}}$ in the X-Y plane for a large volume of the Galactic disk (6 < R < 16 kpc; -20 < φ < 50°; $| Z| \lt 1$ kpc). A clear signature where $\overline{{V}_{z}}$ increases with R is dete…
Low-cost precursor of an interstellar mission
Heller, René; Hippke, Michael; Kervella, Pierre +1 more
The solar photon pressure provides a viable source of thrust for spacecraft in the solar system. Theoretically it could also enable interstellar missions, but an extremely small mass per cross section area is required to overcome the solar gravity. We identify aerographite, a synthetic carbon-based foam with a density of 0.18 kg m-3 (15…
Improved Infrared Photometry and a Preliminary Parallax Measurement for the Extremely Cold Brown Dwarf CWISEP J144606.62-231717.8
Meisner, Aaron M.; Cushing, Michael C.; Kirkpatrick, J. Davy +6 more
We present follow-up Spitzer observations at 3.6 µm (ch1) and 4.5 µm (ch2) of CWISEP J144606.62-231717.8, one of the coldest known brown dwarfs in the solar neighborhood. This object was found by mining the Wide-field Infrared Survey Explorer (WISE) and NEOWISE data via the CatWISE Preliminary Catalog by Meisner et al., where an initia…
First detection of NHD and ND2 in the interstellar medium. Amidogen deuteration in IRAS 16293-2422
Caselli, P.; Sipilä, O.; Bizzocchi, L. +7 more
Context. Deuterium fractionation processes in the interstellar medium (ISM) have been shown to be highly efficient in the family of nitrogen hydrides. To date, observations have been limited to ammonia (NH2D, NHD2, ND3) and imidogen radical (ND) isotopologues.
Aims: We want to explore the high-frequency window…