Search Publications
Direct imaging discovery of a super-Jovian around the young Sun-like star AF Leporis
De Rosa, Robert J.; Nielsen, Eric L.; Hirsch, Lea A. +5 more
Context. Expanding the sample of directly imaged companions to nearby, young stars that are amenable to detailed astrometric and spectroscopic studies is critical for the continued development and validation of theories of their evolution and atmospheric processes.
Aims: The recent release of the Gaia astrometric catalog allows us to efficien…
Accretion geometry of the neutron star low mass X-ray binary Cyg X-2 from X-ray polarization measurements
Antonelli, L. A.; Costa, E.; Bianchi, S. +92 more
We report spectro-polarimetric results of an observational campaign of the bright neutron star low-mass X-ray binary Cyg X-2 simultaneously observed by IXPE, NICER, and INTEGRAL. Consistently with previous results, the broad-band spectrum is characterized by a lower-energy component, attributed to the accretion disc with kTin ≈ 1 keV, p…
The First JWST Spectrum of a GRB Afterglow: No Bright Supernova in Observations of the Brightest GRB of all Time, GRB 221009A
Le Floc'h, E.; D'Avanzo, P.; Campana, S. +57 more
We present James Webb Space Telescope (JWST) and Hubble Space Telescope (HST) observations of the afterglow of GRB 221009A, the brightest gamma-ray burst (GRB) ever observed. This includes the first mid-IR spectra of any GRB, obtained with JWST/Near Infrared Spectrograph (0.6-5.5 micron) and Mid-Infrared Instrument (5-12 micron), 12 days after the…
The Empirical Limits of Gyrochronology
Bouma, Luke G.; Hillenbrand, Lynne A.; Palumbo, Elsa K.
The promise of gyrochronology is that, given a star's rotation period and mass, its age can be inferred. The reality of gyrochronology is complicated by effects other than ordinary magnetized braking that alter stellar rotation periods. In this work, we present an interpolation-based gyrochronology framework that reproduces the time- and mass-depe…
The LOFAR Two-Metre Sky Survey. VI. Optical identifications for the second data release
Prandoni, I.; Shimwell, T. W.; Vaccari, M. +49 more
The second data release of the LOFAR Two-Metre Sky Survey (LoTSS) covers 27% of the northern sky, with a total area of ~5700 deg1. The high angular resolution of LOFAR with Dutch baselines (6 arcsec) allows us to carry out optical identifications of a large fraction of the detected radio sources without further radio followup; however, …
Gas phase Elemental abundances in Molecular cloudS (GEMS). VII. Sulfur elemental abundance
Bachiller, R.; Gerin, M.; Goicoechea, J. R. +18 more
Context. Gas phase Elemental abundances in molecular CloudS (GEMS) is an IRAM 30-m Large Program aimed at determining the elemental abundances of carbon (C), oxygen (O), nitrogen (N), and sulfur (S) in a selected set of prototypical star-forming filaments. In particular, the elemental abundance of S remains uncertain by several orders of magnitude…
Spatial variations in aromatic hydrocarbon emission in a dust-rich galaxy
Hutchison, Taylor A.; Rigby, Jane R.; Whitaker, Katherine E. +36 more
Dust grains absorb half of the radiation emitted by stars throughout the history of the universe, re-emitting this energy at infrared wavelengths1-3. Polycyclic aromatic hydrocarbons (PAHs) are large organic molecules that trace millimetre-size dust grains and regulate the cooling of interstellar gas within galaxies4,5. Obser…
The Gas and Stellar Content of a Metal-poor Galaxy at z = 8.496 as Revealed by JWST and ALMA
Schaerer, D.; Magdis, G. E.; Bauer, F. E. +27 more
We present a joint analysis of the galaxy S04590 at z = 8.496 based on NIRSpec, NIRCam, and NIRISS observations obtained as part of the Early Release Observations program of the James Webb Space Telescope (JWST) and the far-infrared [C II] 158 µm emission line detected by dedicated Atacama Large Millimeter/submillimeter Array (ALMA) observat…
Observations of the planetary nebula SMP LMC 058 with the JWST MIRI medium resolution spectrometer
Fox, O. D.; Kavanagh, P. J.; Larson, Kirsten L. +21 more
During the commissioning of JWST, the medium-resolution spectrometer (MRS) on the mid-infrared instrument (MIRI) observed the planetary nebula SMP LMC 058 in the Large Magellanic Cloud. The MRS was designed to provide medium resolution (R = λ/Δλ) 3D spectroscopy in the whole MIRI range. SMP LMC 058 is the only source observed in JWST commissioning…
Astrometric Accelerations as Dynamical Beacons: A Giant Planet Imaged inside the Debris Disk of the Young Star AF Lep
Jensen-Clem, Rebecca; Crepp, Justin R.; Zhou, Yifan +13 more
We present the direct-imaging discovery of a giant planet orbiting the young star AF Lep, a 1.2 M ⊙ member of the 24 ± 3 Myr β Pic moving group. AF Lep was observed as part of our ongoing high-contrast imaging program targeting stars with astrometric accelerations between Hipparcos and Gaia that indicate the presence of substellar compa…