Search Publications
HD 202206: A Circumbinary Brown Dwarf System
Harrison, Thomas E.; Benedict, G. Fritz
Using Hubble Space Telescope Fine Guidance Sensor astrometry and previously published radial velocity measures, we explore the exoplanetary system HD 202206. Our modeling results in a parallax, {π }{abs}=21.96+/- 0.12 milliseconds of arc, a mass for HD 202206 B of {{ M }}B={0.089}-0.006+0.007 {{ M }}
On the Orbital Inclination of Proxima Centauri b
Kane, Stephen R.; Gelino, Dawn M.; Turnbull, Margaret C.
The field of exoplanetary science has seen discovery rates increase dramatically over recent years, due largely to the data from the Kepler mission. Even so, individual discoveries of planets orbiting nearby stars are very important for studies of characterization and near-term follow-up prospects. The recent discovery of a terrestrial planet cand…
Determining Empirical Stellar Masses and Radii from Transits and Gaia Parallaxes as Illustrated by Spitzer Observations of KELT-11b
Pepper, Joshua; Stassun, Keivan G.; Siverd, Robert J. +8 more
Using the Spitzer Space Telescope, we observed a transit at 3.6 µm of KELT-11b. We also observed three partial planetary transits from the ground. We simultaneously fit these observations, ground-based photometry from Pepper et al., radial velocity data from Pepper et al., and a spectral energy distribution (SED) model using catalog magnitud…
The Kinematics of the Permitted C II λ6578 Line in a Large Sample of Planetary Nebulae
Suárez, Genaro; Richer, Michael G.; López, José Alberto +1 more
We present spectroscopic observations of the C II λ6578 permitted line for 83 lines of sight in 76 planetary nebulae at high spectral resolution, most of them obtained with the Manchester Echelle Spectrograph on the 2.1 m telescope at the Observatorio Astronómico Nacional on the Sierra San Pedro Mártir. We study the kinematics of the C II λ6578 pe…
The Structure of the Young Star Cluster NGC 6231. I. Stellar Population
Gromadzki, Mariusz; Feigelson, Eric D.; Getman, Konstantin V. +4 more
NGC 6231 is a young cluster (age ∼2-7 Myr) dominating the Sco OB1 association (distance ∼1.59 kpc) with ∼100 O and B stars and a large pre-main-sequence stellar population. We combine a reanalysis of archival Chandra X-ray data with multiepoch near-infrared (NIR) photometry from the VISTA Variables in the Vía Lactéa (VVV) survey and published opti…
Properties of the Irregular Satellite System around Uranus Inferred from K2, Herschel, and Spitzer Observations
Pál, A.; Molnár, L.; Marton, G. +10 more
In this paper, we present visible-range light curves of the irregular Uranian satellites Sycorax, Caliban, Prospero, Ferdinand, and Setebos taken with the Kepler Space Telescope over the course of the K2 mission. Thermal emission measurements obtained with the Herschel/PACS and Spitzer/MIPS instruments of Sycorax and Caliban were also analyzed and…
Binary Star Orbits. V. The Nearby White Dwarf/Red Dwarf Pair 40 Eri BC
Mason, Brian D.; Hartkopf, William I.; Miles, Korie N.
A new relative orbit solution with new dynamical masses is determined for the nearby white dwarf-red dwarf pair 40 Eri BC. The period is 230.29 ± 0.68 years. It is predicted to close slowly over the next half-century, getting as close as 1"32 in early 2066. We determine masses of 0.573 ± 0.018 M⊙ for the white dwarf and 0.2036 ± 0.0064 …
Constraining Accretion Signatures of Exoplanets in the TW Hya Transitional Disk
Tamura, Motohide; Uyama, Taichi; Hashimoto, Jun +4 more
We present a near-infrared direct imaging search for accretion signatures of possible protoplanets around the young stellar object (YSO) TW Hya, a multi-ring disk exhibiting evidence of planet formation. The Paβ line (1.282 µm) is an indication of accretion onto a protoplanet, and its intensity is much higher than that of blackbody radiation…
Hierarchical Probabilistic Inference of the Color-Magnitude Diagram and Shrinkage of Stellar Distance Uncertainties
Leistedt, Boris; Hogg, David W.
We present a hierarchical probabilistic model for improving geometric stellar distance estimates using color-magnitude information. This is achieved with a data-driven model of the color-magnitude diagram, not relying on stellar models but instead on the relative abundances of stars in color-magnitude cells, which are inferred from very noisy magn…
Beyond 3 au from the Sun: The Hypervolatiles CH4, C2H6, and CO in the Distant Comet C/2006 W3 (Christensen)
Villanueva, Geronimo L.; Mumma, Michael J.; DiSanti, Michael A. +5 more
Comet C/2006 W3 (Christensen) remained outside a heliocentric distance (R h) of 3.1 au throughout its apparition, but it presented an exceptional opportunity to directly sense a suite of molecules released from its nucleus. The Cryogenic Infrared Echelle Spectrograph at ESO-VLT detected infrared emissions from the three “hypervolatiles”…