Search Publications
Double Image Polarimeter—Ultra Fast: Simultaneous Three-color (BV R) Polarimeter with Electron-multiplying Charge-coupled Devices
Piirola, Vilppu; Poutanen, Juri; Berdyugin, Andrei V. +2 more
We describe a new instrument capable of high-precision (10-5) polarimetric observations simultaneously in three passbands (BVR). The instrument utilizes electron-multiplying charge-coupled device (EM CCD) cameras for high efficiency and fast image readout. The key features of the Double Image Polarimeter—Ultra Fast (DIPol-UF) are: (i) t…
TOI-532b: The Habitable-zone Planet Finder confirms a Large Super Neptune in the Neptune Desert orbiting a metal-rich M-dwarf host
Kobulnicky, Henry A.; Cochran, William D.; Mahadevan, Suvrath +30 more
We confirm the planetary nature of TOI-532b, using a combination of precise near-infrared radial velocities with the Habitable-zone Planet Finder, Transiting Exoplanet Survey Satellite (TESS) light curves, ground-based photometric follow up, and high-contrast imaging. TOI-532 is a faint (J ~ 11.5) metal-rich M dwarf with Teff = 3957 ± 6…
A Lyα Transit Left Undetected: the Environment and Atmospheric Behavior of K2-25b
Youngblood, Allison; Mann, Andrew W.; Charbonneau, David +6 more
K2-25b is a Neptune-sized exoplanet (3.45R⊕) that orbits its M4.5 host with a period of 3.48 days. Due to its membership in the Hyades Cluster, the system has a known age (727 ± 75 Myr). K2-25b's youth and its similarities with Gl 436b suggested that K2-25b could be undergoing strong atmospheric escape. We observed two transits of K2-25…
Gemini Planet Imager Spectroscopy of the Dusty Substellar Companion HD 206893 B
Duchêne, G.; Doyon, R.; Saumon, D. +55 more
We present new near-infrared Gemini Planet Imager (GPI) spectroscopy of HD 206893 B, a substellar companion orbiting within the debris disk of its F5V star. The J, H, K1, and K2 spectra from GPI demonstrate the extraordinarily red colors of the object, confirming it as the reddest substellar object observed to date. The significant flux increase t…
Planet Occurrence Rate Correlated to Stellar Dynamical History: Evidence from Kepler and Gaia
Zhou, Ji-Lin; Dai, Yuan-Zhe; Liu, Hui-Gen +1 more
The dynamical history of stars influences the formation and evolution of planets significantly. To explore the influence of dynamical history on the planet formation and evolution using observations, we assume stars that experienced significantly different dynamical histories tend to have different relative velocities. Utilizing the accurate Gaia-…
The Global Magneto-ionic Medium Survey: A Faraday Depth Survey of the Northern Sky Covering 1280-1750 MHz
Leahy, J. P.; Kothes, R.; Gaensler, B. M. +17 more
The Galactic interstellar medium hosts a significant magnetic field, which can be probed through the synchrotron emission produced from its interaction with relativistic electrons. Linearly polarized synchrotron emission is generated throughout the Galaxy and, at longer wavelengths, modified along nearly every path by Faraday rotation in the inter…
Characterizing the Protolunar Disk of the Accreting Companion GQ Lupi B
Kesseli, Aurora Y.; Brinchmann, Jarle; Milli, Julien +11 more
GQ Lup B is a young and accreting, substellar companion that appears to drive a spiral arm in the circumstellar disk of its host star. We report high-contrast imaging observations of GQ Lup B with VLT/NACO at 4-5 µm and medium-resolution integral field spectroscopy with VLT/MUSE. The optical spectrum is consistent with an M9 spectral type, s…
TESS Discovery of a Super-Earth and Three Sub-Neptunes Hosted by the Bright, Sun-like Star HD 108236
Butler, R. Paul; Kristiansen, Martti H.; Terentev, Ivan A. +59 more
We report the discovery and validation of four extrasolar planets hosted by the nearby, bright, Sun-like (G3V) star HD 108236 using data from the Transiting Exoplanet Survey Satellite (TESS). We present transit photometry, reconnaissance, and precise Doppler spectroscopy, as well as high-resolution imaging, to validate the planetary nature of the …
Quasi-periodic Oscillations in the TESS Light Curve of TX Col, a Diskless Intermediate Polar on the Precipice of Forming an Accretion Disk
Garnavich, Peter; Littlefield, Colin; Szkody, Paula +4 more
One of the fundamental properties of an intermediate polar is the dynamical nature of the accretion flow as it encounters the white dwarf's (WD's) magnetosphere. Many works have presumed a dichotomy between disk-fed accretion, in which the WD accretes from a Keplerian disk, and stream-fed accretion, in which the matter stream from the donor star d…
Speckle Interferometry at SOAR in 2020
Henry, Todd J.; Tokovinin, Andrei; Mann, Andrew W. +3 more
The results of speckle interferometric observations at the 4.1 m Southern Astrophysical Research Telescope in 2020, as well as earlier unpublished data, are given, totaling 1735 measurements of 1288 resolved pairs and nonresolutions of 1177 targets. We resolved for the first time 59 new pairs or subsystems in known binaries, mostly among nearby dw…