Search Publications
Mass Measurements in Protoplanetary Disks from Hydrogen Deuteride
Henning, Th.; van Dishoeck, E. F.; Pontoppidan, K. M. +8 more
The total gas mass of a protoplanetary disk is a fundamental, but poorly determined, quantity. A new technique has been demonstrated to assess directly the bulk molecular gas reservoir of molecular hydrogen using the HD J = 1-0 line at 112 µm. In this work we present a Herschel Space Observatory 10 survey of six additional T Tauri…
A Precise Determination of the Mid-infrared Interstellar Extinction Law Based on the APOGEE Spectroscopic Survey
Gao, Jian; Wang, Shu; Li, Aigen +3 more
A precise measure of the mid-infrared interstellar extinction law is crucial for investigating the properties of interstellar dust, especially larger-sized grains. Based on the stellar parameters derived from the SDSS-III/Apache Point Observatory Galaxy Evolution Experiment (APOGEE) spectroscopic survey, we select a large sample of G-type and K-ty…
AGN are cooler than you think: the intrinsic far-IR emission from QSOs
Oliver, S. J.; Page, M. J.; Symeonidis, M. +4 more
We present an intrinsic AGN spectral energy distribution (SED) extending from the optical to the submm, derived with a sample of unobscured, optically luminous (νLν,5100 > 1043.5 erg s-1) QSOs at z < 0.18 from the Palomar Green survey. The intrinsic AGN SED was computed by removing the contribution from stars…
A Comprehensive Census of Nearby Infrared Excess Stars
Song, Inseok; Cotten, Tara H.
The conclusion of the Wide-Field Infrared Survey Explorer (WISE) mission presents an opportune time to summarize the history of using excess emission in the infrared as a tracer of circumstellar material and exploit all available data for future missions such as the James Webb Space Telescope. We have compiled a catalog of infrared excess stars fr…
Incidence of debris discs around FGK stars in the solar neighbourhood
Heras, A. M.; Fridlund, M.; Krivov, A. V. +16 more
Context. Debris discs are a consequence of the planet formation process and constitute the fingerprints of planetesimal systems. Their counterparts in the solar system are the asteroid and Edgeworth-Kuiper belts.
Aims: The aim of this paper is to provide robust numbers for the incidence of debris discs around FGK stars in the solar neighbourh…
The evolved-star dust budget of the Small Magellanic Cloud: the critical role of a few key players
Boyer, M. L.; Meixner, M.; Kemper, F. +3 more
The life cycle of dust in the interstellar medium is heavily influenced by outflows from asymptotic giant branch (AGB) and red supergiant (RSG) stars, a large fraction of which is contributed by a few very dusty sources. We compute the dust input to the Small Magellanic Cloud (SMC) by fitting the multi-epoch mid-infrared spectral energy distributi…
Searching for Cool Dust in the Mid-to-far Infrared: The Mass-loss Histories of the Hypergiants µ Cep, VY CMa, IRC+10420, and ρ Cas
Gehrz, Robert D.; Humphreys, Roberta M.; Jones, Terry J. +6 more
We present mid- and far-IR imaging of four famous hypergiant stars: the red supergiants µ Cep and VY CMa, and the warm hypergiants IRC +10420 and ρ Cas. Our 11-37 µm SOFIA/FORCAST imaging probes cool dust not detected in visual and near-IR imaging studies. Adaptive optics 8-12 µm imaging of µ Cep and IRC +10420 with MMT/MIR…
The First Spectrum of the Coldest Brown Dwarf
Fortney, Jonathan J.; Marley, Mark S.; Faherty, Jacqueline K. +6 more
The recently discovered brown dwarf WISE 0855 presents the first opportunity to directly study an object outside the solar system that is nearly as cold as our own gas giant planets. However, the traditional methodology for characterizing brown dwarfs—near-infrared spectroscopy—is not currently feasible, as WISE 0855 is too cold and faint. To char…
The near-to-mid infrared spectrum of quasars
Alonso-Herrero, Almudena; Hatziminaoglou, Evanthia; Hernán-Caballero, Antonio +1 more
We analyse a sample of 85 luminous (log (νLν(3 µm)/erg s-1) > 45.5) quasars with rest frame ∼2-11 µm spectroscopy from AKARI and Spitzer. Their high luminosity allows a direct determination of the near-infrared quasar spectrum free from host galaxy emission. A semi-empirical model consisting of a single templat…
Detailed homogeneous abundance studies of 14 Galactic s-process enriched post-AGB stars: In search of lead (Pb)
Van Winckel, H.; Kamath, D.; Karakas, A. I. +4 more
Context. This paper is part of a larger project in which we systematically study the chemical abundances of Galactic and extragalactic post-asymptotic giant branch (post-AGB) stars. The goal at large is to provide improved observational constraints to the models of the complex interplay between the AGB s-process nucleosynthesis and the associated …