Search Publications
SPLUS J210428.01-004934.2: An Ultra Metal-poor Star Identified from Narrowband Photometry
Lee, Young Sun; Placco, Vinicius M.; Roederer, Ian U. +6 more
We report on the discovery of SPLUS J210428.01-004934.2, an ultra metal-poor (UMP) star first identified from the narrowband photometry of the Southern Photometric Local Universe Survey (S-PLUS) Data Release 1, in the SDSS Stripe 82 region. Follow-up medium- and high-resolution spectroscopy (with Gemini South and Magellan-Clay, respectively) confi…
Stellar Rotation of T Tauri Stars in the Orion Star-forming Complex
Stassun, Keivan G.; Kounkel, Marina; Briceño, Cesar +14 more
We present a large-scale study of stellar rotation for T Tauri stars in the Orion star-forming complex. We use the projected rotational velocity ( $v\sin (i)$ vsin(i) ) estimations reported by the APOGEE-2 collaboration as well as individual masses and ages derived from the position of the stars in the HR diagram, considering Gaia-EDR3 parallaxes …
First light observations of the solar wind in the outer corona with the Metis coronagraph
Heinzel, P.; Vial, J. -C.; Woch, J. +65 more
In this work, we present an investigation of the wind in the solar corona that has been initiated by observations of the resonantly scattered ultraviolet emission of the coronal plasma obtained with UVCS-SOHO, designed to measure the wind outflow speed by applying Doppler dimming diagnostics. Metis on Solar Orbiter complements the UVCS spectroscop…
A Detailed Characterization of HR 8799's Debris Disk with ALMA in Band 7
Stapelfeldt, Karl R.; Hales, Antonio S.; Casassus, Simon +8 more
The exoplanetary system of HR 8799 is one of the rare systems in which multiple planets have been directly imaged. Its architecture is strikingly similar to that of the solar system, with the four imaged giant planets surrounding a warm dust belt analogous to the Asteroid Belt, and themselves being surrounded by a cold dust belt analog to the Kuip…
Physics of ULIRGs with MUSE and ALMA: The PUMA project. II. Are local ULIRGs powered by AGN? The subkiloparsec view of the 220 GHz continuum
Rigopoulou, D.; Colina, L.; van der Werf, P. +11 more
We analyze new high-resolution (400 pc) ∼220 GHz continuum and CO(2-1) Atacama Large Millimeter Array (ALMA) observations of a representative sample of 23 local (z < 0.165) ultra-luminous infrared systems (ULIRGs; 34 individual nuclei) as part of the "Physics of ULIRGs with MUSE and ALMA" (PUMA) project. The deconvolved half-light radii of the …
HST grism spectroscopy of z ∼ 3 massive quiescent galaxies. Approaching the metamorphosis
Cimatti, A.; Daddi, E.; Gobat, R. +6 more
Tracing the emergence of the massive quiescent galaxy (QG) population requires the build-up of reliable quenched samples by distinguishing these systems from red, dusty star-forming sources. We present Hubble Space Telescope WFC3/G141 grism spectra of ten quiescent galaxy candidates selected at 2.5 < z < 3.5 in the COSMOS field. Spectroscopi…
Discovery of a Fast Iron Low-ionization Outflow in the Early Evolution of the Nearby Tidal Disruption Event AT 2019qiz
Cenko, S. B.; Veilleux, S.; Filippenko, Alexei V. +16 more
We report the results of ultraviolet (UV) and optical photometric and spectroscopic analysis of the tidal disruption event (TDE) AT 2019qiz. Our follow-up observations started <10 days after the source began to brighten in the optical and lasted for a period of six months. Our late-time host-dominated spectrum indicates that the host galaxy lik…
Highlights of Discoveries for δ Scuti Variable Stars From the Kepler Era
Guzik, Joyce Ann
The NASAKeplerand follow-on K2 mission (2009–2018) left a legacy of data and discoveries, finding thousands of exoplanets, and also obtaining high-precision long time-series data for hundreds of thousands of stars, including many types of pulsating variables. Here we highlight a few of the ongoing discoveries fromKeplerdata on δ Scuti pulsating va…
Action-based distribution function modelling for constraining the shape of the Galactic dark matter halo
Hattori, Kohei; Vasiliev, Eugene; Valluri, Monica
We estimate the 3D density profile of the Galactic dark matter (DM) halo within r ≲ 30 kpc from the Galactic centre by using the astrometric data for halo RR Lyrae stars from Gaia DR2. We model both the stellar halo distribution function and the Galactic potential, fully taking into account the survey selection function, the observational errors, …
Low-luminosity Galaxies in the Early Universe Have Observed Sizes Similar to Star Cluster Complexes
Oesch, P. A.; Bouwens, R. J.; Illingworth, G. D. +3 more
We compare the sizes and luminosities of faint z = 6-8 galaxies magnified by the Hubble Frontier Fields clusters with star-forming regions, as well as more evolved objects, in the nearby universe. Our high-redshift comparison sample includes 330 z = 6-8 galaxies, for which size measurements were made as part of a companion study where lensing magn…