Search Publications
SCExAO/CHARIS Direct Imaging Discovery of a 20 au Separation, Low-mass Ratio Brown Dwarf Companion to an Accelerating Sun-like Star
Currie, Thayne; Kwon, Jungmi; Tamura, Motohide +27 more
We present the direct imaging discovery of a substellar companion to the nearby Sun-like star, HD 33632 Aa, at a projected separation of ∼20 au, obtained with SCExAO/CHARIS integral field spectroscopy complemented by Keck/NIRC2 thermal infrared imaging. The companion, HD 33632 Ab, induces a 10.5σ astrometric acceleration on the star as detected wi…
How stellar rotation shapes the colour-magnitude diagram of the massive intermediate-age star cluster NGC 1846
Martocchia, S.; Salaris, M.; Cabrera-Ziri, I. +19 more
We present a detailed study of stellar rotation in the massive 1.5 Gyr old cluster NGC 1846 in the Large Magellanic Cloud. Similar to other clusters at this age, NGC 1846 shows an extended main-sequence turn-off (eMSTO), and previous photometric studies have suggested it could be bimodal. In this study, we use MUSE integral-field spectroscopy to m…
Gaia search for stellar companions of TESS Objects of Interest
Mugrauer, Markus; Michel, Kai-Uwe
The first results of a new survey, which explores the second data release of the ESA Gaia mission, are reported in order to search for stellar companions of (Community) TESS Objects of Interest and to characterize their properties. In total, 193 binary and 15 hierarchical triple star systems are presented, detected among 1,391 target stars, which …
Plateau de Bure High-z Blue Sequence Survey 2 (PHIBSS2): Search for Secondary Sources, CO Luminosity Functions in the Field, and the Evolution of Molecular Gas Density through Cosmic Time
Lenkić, Laura; Bolatto, Alberto D.; Neri, Roberto +8 more
We report on the results of a search for serendipitous sources in CO emission in 110 cubes targeting CO(2 - 1), CO(3 - 2), and CO(6 - 5) at z ∼ 1-2 from the second Plateau de Bure High-z Blue Sequence Survey (PHIBSS2). The PHIBSS2 observations were part of a 4 yr legacy program at the IRAM Plateau de Bure Interferometer aimed at studying early gal…
Aurora in the Polar Cap: A Review
Frey, Harald U.; Kullen, Anita; Maggiolo, Romain +5 more
This paper reviews our current understanding of auroral features that appear poleward of the main auroral oval within the polar cap, especially those that are known as Sun-aligned arcs, transpolar arcs, or theta auroras. They tend to appear predominantly during periods of quiet geomagnetic activity or northwards directed interplanetary magnetic fi…
A Relationship between Stellar Age and Spot Coverage
Morris, Brett M.
We investigate starspot distributions consistent with space-based photometry of F, G, and K stars in six stellar associations ranging in age from 10 Myr to 4 Gyr. We show that a simple light-curve statistic called the "smoothed amplitude" is proportional to stellar age as t-1/2, following a Skumanich-like spin-down relation. We marginal…
TESS unveils the phase curve of WASP-33b. Characterization of the planetary atmosphere and the pulsations from the star
Mallonn, M.; von Essen, C.; Antoci, V. +4 more
We present the detection and characterization of the full-orbit phase curve and secondary eclipse of the ultra-hot Jupiter WASP-33b at optical wavelengths, along with the pulsation spectrum of the host star. We analyzed data collected by the Transiting Exoplanet Survey Satellite (TESS) in sector 18. WASP-33b belongs to a very short list of highly …
A Deep CFHT Optical Search for a Counterpart to the Possible Neutron Star-Black Hole Merger GW190814
Safi-Harb, Samar; Drout, Maria R.; Moon, Dae-Sik +10 more
We present a wide-field optical imaging search for electromagnetic counterparts to the likely neutron star-black hole (NS-BH) merger GW190814/S190814bv. This compact binary merger was detected through gravitational waves by the LIGO/Virgo interferometers, with masses suggestive of an NS-BH merger. We imaged the LIGO/Virgo localization region using…
UV and Lyα luminosity functions of galaxies and star formation rate density at the end of HI reionization from the VIMOS UltraDeep Survey (VUDS)
Maccagni, D.; Cimatti, A.; Ilbert, O. +25 more
Context. The star formation rate density (SFRD) evolution presents an area of great interest in the studies of galaxy evolution and reionization. The current constraints of SFRD at z > 5 are based on the rest-frame UV luminosity functions with the data from photometric surveys. The VIMOS UltraDeep Survey (VUDS) was designed to observe galaxies …
Near-ultraviolet Transmission Spectroscopy of HD 209458b: Evidence of Ionized Iron Beyond the Planetary Roche Lobe
France, Kevin; Cubillos, Patricio E.; Koskinen, Tommi +5 more
The inflated transiting hot Jupiter HD 209458b is one of the best studied objects since the beginning of exoplanet characterization. Transmission observations of this system between the mid-infrared and the far-ultraviolet have revealed the signature of atomic, molecular, and possibly aerosol species in the lower atmosphere of the planet, as well …