Search Publications
K2-287 b: An Eccentric Warm Saturn Transiting a G-dwarf
Henning, Thomas; Jordán, Andrés; Espinoza, Néstor +23 more
We report the discovery of K2-287b, a Saturn mass planet orbiting a G-dwarf with a period of P ≈ 15 days. First uncovered as a candidate using K2 campaign 15 data, follow-up photometry and spectroscopy were used to determine a mass {M}{{P}}=0.317+/- 0.026 {M}{{J}}, radius {R}{{P}}=0.833+/- 0.013 {R}{{J}}…
Physical Properties of the Close-in Tertiary in the Southern Triple-lined System VZ Lib
Qian, S. -B.; Liao, W. -P.; Sarotsakulchai, T.
VZ Lib is a southern triple-lined system. By analyzing all available times of light minima, orbital period changes are revisited in detail. We discovered that the observed-calculated (O - C) curve shows a long-term period decrease at a rate of {dP}/{dt}=-2.25× {10}-7 {days yr}}-1, revealing a mass transfer from the more massi…
The Blueshift of the C IV Broad Emission Line in QSOs
Bian, Wei-Hao; Ge, Xue; Zhao, Bi-Xuan +1 more
For the sample from Ge et al. of 87 low-z Palomar-Green quasi-stellar objects (QSOs) and 130 high-z QSOs (0 < z < 5) with {{H}}β -based single-epoch supermassive black hole masses, we perform a uniform decomposition of the C IV λ1549 broad-line profile. Based on the rest frame defined by the [O III] λ5007 narrow emission line, a medium-stron…
Spectroscopic Mass and Host-star Metallicity Measurements for Newly Discovered Microlensing Planet OGLE-2018-BLG-0740Lb
Kollmeier, Juna A.; Morrell, Nidia; Han, Cheongho +67 more
We report the discovery of the microlensing planet OGLE-2018-BLG-0740Lb. The planet is detected with a very strong signal of Δχ 2 ∼ 4630, but the interpretation of the signal suffers from two types of degeneracies. One type is caused by the previously known close/wide degeneracy, and the other is caused by an ambiguity between two solut…
Resolved Imaging of the AR Puppis Circumbinary Disk
Marshall, J. P.; Ertel, S.; Milli, J. +14 more
Circumbinary disks are common around post-asymptotic giant branch (post-AGB) stars with a stellar companion on orbital timescales of a few 100 to few 1000 days. The presence of a disk is usually inferred from the system’s spectral energy distribution and confirmed, for a sub-sample, by interferometric observations. We used the Spectro-Polarimetric…
K2-288Bb: A Small Temperate Planet in a Low-mass Binary System Discovered by Citizen Scientists
Schlieder, Joshua E.; Howard, Andrew W.; Petigura, Erik A. +23 more
Observations from the Kepler and K2 missions have provided the astronomical community with unprecedented amounts of data to search for transiting exoplanets and other astrophysical phenomena. Here, we present K2-288, a low-mass binary system (M2.0 ± 1.0; M3.0 ± 1.0) hosting a small (R p = 1.9 R ⊕), temperate (T eq …
Visual Orbits of Spectroscopic Binaries with the CHARA Array. I. HD 224355
Gies, Douglas R.; Lester, Kathryn V.; Monnier, John D. +5 more
We present the visual orbit of the double-lined spectroscopic binary HD 224355 from interferometric observations with the CHARA Array, as well as an updated spectroscopic analysis using echelle spectra from the Apache Point Observatory 3.5 m telescope. By combining the visual and spectroscopic orbital solutions, we find the binary components to ha…
Lifetimes and Occurrence Rates of Dark Vortices on Neptune from 25 Years of Hubble Space Telescope Images
Wong, Michael H.; Simon, Amy A.; Hsu, Andrew I.
We scoured the full set of blue-wavelength Hubble Space Telescope images of Neptune, finding one additional dark spot in new Hubble data beyond those discovered in 1989, 1994, 1996, and 2015. We report the complete disappearance of the SDS-2015 dark spot, using new Hubble data taken on 2018 September 9-10, as part of the Outer Planet Atmospheres L…
Luminous and Variable Stars in NGC 2403 and M81
Humphreys, Roberta M.; Davidson, Kris; Gordon, Michael S. +2 more
We present the results of spectroscopy and multi-wavelength photometry of luminous and variable star candidates in the nearby spiral galaxies NGC 2403 and M81. We discuss specific classes of stars, the Luminous Blue Variables (LBVs), B[e] supergiants (sgB[e]), and the high-luminosity yellow hypergiants. We identify two new LBV candidates, and thre…
K2-291b: A Rocky Super-Earth in a 2.2 day Orbit
Vanderburg, Andrew; López-Morales, Mercedes; Latham, David W. +43 more
K2-291 is a solar-type star with a radius of R * = 0.899 ± 0.034 R ⊙ and mass of M* = 0.934 ± 0.038 M ⊙. From the K2 C13 data, we found one super-Earth planet (R p = {1.589}-0.072+0.095 R ⊕) transiting this star on a short period orbit (P = {2.225177}-6.…