Search Publications
A Coordinated X-Ray and Optical Campaign of the Nearest Massive Eclipsing Binary, δ Orionis Aa. IV. A Multiwavelength, Non-LTE Spectroscopic Analysis
Corcoran, M. F.; Hamann, W. -R.; Nazé, Y. +13 more
Eclipsing systems of massive stars allow one to explore the properties of their components in great detail. We perform a multi-wavelength, non-LTE analysis of the three components of the massive multiple system δ Ori A, focusing on the fundamental stellar properties, stellar winds, and X-ray characteristics of the system. The primary’s distance-in…
Planck intermediate results. XXVIII. Interstellar gas and dust in the Chamaeleon clouds as seen by Fermi LAT and Planck
Kneissl, R.; Miville-Deschênes, M. -A.; Boulanger, F. +198 more
The nearby Chamaeleon clouds have been observed in γ rays by the Fermi Large Area Telescope (LAT) and in thermal dust emission by Planck and IRAS. Cosmic rays and large dust grains, if smoothly mixed with gas, can jointly serve with the H i and 12CO radio data to (i) map the hydrogen column densities, NH, in the different gas…
Variability of the Martian thermosphere during eight Martian years as simulated by a ground-to-exosphere global circulation model
Forget, F.; López-Valverde, M. A.; García-Comas, M. +3 more
Using a ground-to-exosphere general circulation model for Mars we have simulated the variability of the dayside temperatures at the exobase during eight Martian years (MY, from MY24 to MY31, approximately from 1998 to 2013), taking into account the observed day-to-day solar and dust load variability. We show that the simulated temperatures are in …
Inflation after false vacuum decay: Observational prospects after Planck
Bousso, Raphael; Harlow, Daniel; Senatore, Leonardo
We assess two potential signals of the formation of our universe by the decay of a false vacuum. Negative spatial curvature is one possibility, but the window for its detection is now small. However, another possible signal is a suppression of the cosmic microwave background (CMB) power spectrum at large angles. This arises from the steepening of …
The Optically Unbiased GRB Host (TOUGH) Survey. VII. The Host Galaxy Luminosity Function: Probing the Relationship between GRBs and Star Formation to Redshift ∼ 6
Milvang-Jensen, B.; Fynbo, J. P. U.; Krühler, T. +12 more
Gamma-ray bursts (GRBs) offer a route to characterizing star-forming galaxies and quantifying high-z star formation that is distinct from the approach of traditional galaxy surveys: GRB selection is independent of dust and probes even the faintest galaxies which can evade detection in flux-limited surveys. However, the exact relation between the G…
Cloud Structure of the Nearest Brown Dwarfs: Spectroscopic Variability of Luhman 16AB from the Hubble Space Telescope
Apai, Dániel; Marley, Mark S.; Bedin, Luigi R. +5 more
The binary brown dwarf WISE J104915.57-531906.1 (also Luhman 16AB), composed of a late-L and early-T dwarf, is a prototypical L/T transition flux reversal binary located at a distance of only 2 pc. Luhman 16B is a known variable whose light curves evolve rapidly. We present a spatially resolved spectroscopic time-series of Luhman 16A and B coverin…
Far-ultraviolet morphology of star-forming filaments in cool core brightest cluster galaxies
Fabian, A. C.; Li, Y.; Combes, F. +17 more
We present a multiwavelength morphological analysis of star-forming clouds and filaments in the central (≲50 kpc) regions of 16 low-redshift (z < 0.3) cool core brightest cluster galaxies. New Hubble Space Telescope imaging of far-ultraviolet continuum emission from young (≲10 Myr), massive (≳5 M⊙) stars reveals filamentary and clump…
Interstellar Detection of Methyl Isocyanate CH3NCO in Sgr B2(N): A Link from Molecular Clouds to Comets
Ziurys, L. M.; Halfen, D. T.; Ilyushin, V. V.
A new interstellar molecule, CH3NCO (methyl isocyanate), has been detected using the 12 m telescope of the Arizona Radio Observatory (ARO). CH3NCO was identified in spectra covering 48 GHz (68-116 GHz) in the 3 mm segment of a broadband survey of Sgr B2(N). Thirty very favorable rotational lines (Ka = 0 and Ka…
Fractures on comet 67P/Churyumov-Gerasimenko observed by Rosetta/OSIRIS
Jorda, L.; Lamy, P. L.; Lara, L. M. +50 more
The Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) experiment onboard the Rosetta spacecraft currently orbiting comet 67P/Churyumov-Gerasimenko has yielded unprecedented views of a comet's nucleus. We present here the first ever observations of meter-scale fractures on the surface of a comet. Some of these fractures form polyg…
Determining the Covering Factor of Compton-thick Active Galactic Nuclei with NuSTAR
Harrison, F. A.; Stern, D.; Zhang, W. W. +19 more
The covering factor of Compton-thick (CT) obscuring material associated with the torus in active galactic nuclei (AGNs) is at present best understood through the fraction of sources exhibiting CT absorption along the line of sight (NH > 1.5 × 1024 cm-2) in the X-ray band, which reveals the average covering facto…