Search Publications
An Evolutionary Study of Volatile Chemistry in Protoplanetary Disks
Wilner, David J.; Cleeves, L. Ilsedore; Andrews, Sean M. +11 more
The volatile composition of a planet is determined by the inventory of gas and ice in the parent disk. The volatile chemistry in the disk is expected to evolve over time, though this evolution is poorly constrained observationally. We present Atacama Large Millimeter/submillimeter Array observations of C18O, C2H, and the isot…
Shadowing and multiple rings in the protoplanetary disk of HD 139614
Ménard, F.; Matter, A.; Henning, T. +20 more
Context. Shadows in scattered light images of protoplanetary disks are a common feature and support the presence of warps or misalignments between disk regions. These warps are possibly caused by an inclined (sub-)stellar companion embedded in the disk.
Aims: We aim to study the morphology of the protoplanetary disk around the Herbig Ae star …
A Very Young Radio-loud Magnetar
Campana, S.; Tiengo, A.; Götz, D. +20 more
The magnetar Swift J1818.0-1607 was discovered in 2020 March when Swift detected a 9 ms hard X-ray burst and a long-lived outburst. Prompt X-ray observations revealed a spin period of 1.36 s, soon confirmed by the discovery of radio pulsations. We report here on the analysis of the Swift burst and follow-up X-ray and radio observations. The burst …
The magnetic field and accretion regime of CI Tau
Moutou, C.; Ménard, F.; Donati, J. -F. +7 more
This paper exploits spectropolarimetric data of the classical T Tauri star CI Tau collected with ESPaDOnS at the Canada-France-Hawaii Telescope, with the aims of detecting and characterizing the large-scale magnetic field that the star hosts, and of investigating how the star interacts with the inner regions of its accretion disc through this fiel…
Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era
Jasniewicz, G.; Lagarde, N.; Smiljanic, R. +7 more
Context. Li is extensively known to be a good tracer of non-standard mixing processes occurring in stellar interiors.
Aims: We present the results of a new large Li survey in red giant stars and combine it with surveys from the literature to probe the impact of rotation-induced mixing and thermohaline double-diffusive instability along stella…
High-resolution Spectroscopy of the GD-1 Stellar Stream Localizes the Perturber near the Orbital Plane of Sagittarius
Conroy, Charlie; Cargile, Phillip A.; Johnson, Benjamin D. +6 more
The 100° long thin stellar stream in the Milky Way halo, GD-1, has an ensemble of features that may be due to dynamical interactions. Using high-resolution MMT/Hectochelle spectroscopy we show that a spur of GD-1-like stars outside of the main stream are kinematically and chemically consistent with the main stream. In the spur, as in the main stre…
Refining the age, emplacement and alteration scenarios of the olivine-rich unit in the Nili Fossae region, Mars
Mangold, N.; Quantin-Nataf, C.; Millot, C. +8 more
The Nili Fossae region of Mars exhibits from remote sensing spectral data the largest exposures of olivine-rich materials on the planet. However, it is not clearly constrained how and when these terrains formed. Some of the proposed scenarios favor a mode of formation closely related to Isidis impact basin: either under intense effusive volcanism …
Keck Observations Confirm a Super-Jupiter Planet Orbiting M Dwarf OGLE-2005-BLG-071L
Lu, Jessica R.; Cole, Andrew A.; Udalski, Andrzej +10 more
We present adaptive optics imaging from the NIRC2 instrument on the Keck II telescope that resolves the exoplanet host (and lens) star as it separates from the brighter source star. These observations yield the K-band brightness of the lens and planetary host star, as well as the lens-source relative proper motion, ${{\boldsymbol{\mu }}}_{\mathrm{…
Obliquity Constraints on an Extrasolar Planetary-mass Companion
Knutson, Heather A.; Morley, Caroline V.; Bowler, Brendan P. +8 more
We place the first constraints on the obliquity of a planetary-mass companion outside of the solar system. Our target is the directly imaged system 2MASS J01225093-2439505 (2M0122), which consists of a 120 Myr 0.4 M⊙ star hosting a 12-27 MJ companion at 50 au. We constrain all three of the system's angular-momentum vectors: h…
GOODS-ALMA: The slow downfall of star formation in z = 2-3 massive galaxies
Magnelli, B.; Daddi, E.; Elbaz, D. +34 more
We investigate the properties of a sample of 35 galaxies, detected with the Atacama Large Millimeter/Submillimeter Array (ALMA) at 1.1 mm in the GOODS-ALMA field (area of 69 arcmin2, resolution = 0.60″, rms ≃ 0.18 mJy beam-1). Using the ultraviolet-to-radio deep multiwavelength coverage of the GOODS-South field, we fit the sp…