Search Publications
Warmer Local Interstellar Medium: A Possible Resolution of the Ulysses-IBEX Enigma
McComas, D. J.; Fuselier, S. A.; Kucharek, H. +9 more
Interstellar Boundary Explorer (IBEX) measurements from 2009-2010 identified a set of possible solutions with very tight coupling between the interstellar He inflow longitude, latitude, speed, and temperature. The center of this allowable parameter space suggested that the heliosphere could be moving more slowly and in a slightly different directi…
Planck intermediate results. XXI. Comparison of polarized thermal emission from Galactic dust at 353 GHz with interstellar polarization in the visible
Kneissl, R.; Miville-Deschênes, M. -A.; Boulanger, F. +193 more
The Planck survey provides unprecedented full-sky coverage of the submillimetre polarized emission from Galactic dust. In addition to the information on the direction of the Galactic magnetic field, this also brings new constraints on the properties of dust. The dust grains that emit the radiation seen by Planck in the submillimetre also extinguis…
Revisiting the relationship between 6 µm and 2-10 keV continuum luminosities of AGN
Hernán-Caballero, A.; Rovilos, E.; Barcons, X. +7 more
We have determined the relation between the AGN luminosities at rest-frame 6 µm associated with the dusty torus emission and at 2-10 keV energies using a complete, X-ray-flux-limited sample of 232 AGN drawn from the Bright Ultra-hard XMM-Newton Survey. The objects have intrinsic X-ray luminosities between 1042 and 1046 …
The VLT/NaCo large program to probe the occurrence of exoplanets and brown dwarfs in wide orbits. I. Sample definition and characterization
Moutou, C.; Henning, T.; Alcalá, J. M. +28 more
Context. Young, close stars are ideal targets for searching planets using the direct imaging technique. The determination of stellar parameters is crucial for the interpretation of imaging survey results, particularly since the luminosity of substellar objects has a strong dependence on system age.
Aims: We have conducted a large program with…
The Event Horizon of M87
Perlman, Eric S.; Kormendy, John; Rieke, Marcia J. +3 more
The 6× {{10}9} {{M}⊙ } supermassive black hole at the center of the giant elliptical galaxy M87 powers a relativistic jet. Observations at millimeter wavelengths with the Event Horizon Telescope have localized the emission from the base of this jet to angular scales comparable to the putative black hole horizon. The jet might…
Decreased specific star formation rates in AGN host galaxies
Koss, Michael; Mushotzky, Richard F.; Rosario, David J. +2 more
We investigate the location of an ultra-hard X-ray selected sample of active galactic nuclei (AGN) from the Swift Burst Alert Telescope (BAT) catalogue with respect to the main sequence (MS) of star-forming galaxies using Herschel-based measurements of the star formation rate (SFR) and M*'s from Sloan Digital Sky Survey photometry where…
Large-scale alignments from WMAP and Planck
Schwarz, Dominik J.; Starkman, Glenn D.; Copi, Craig J. +1 more
We revisit the alignments of the largest structures observed in the cosmic microwave background (CMB) using the seven and nine-year Wilkinson Microwave Anisotropy Probe (WMAP) and first-year Planck data releases. The observed alignments - the quadrupole with the octopole and their joint alignment with the direction of our motion with respect to th…
The stellar initial mass function of early-type galaxies from low to high stellar velocity dispersion: homogeneous analysis of ATLAS3D and Sloan Lens ACS galaxies
Treu, Tommaso; Cappellari, Michele; Ciotti, Luca +2 more
We present an investigation about the shape of the initial mass function (IMF) of early-type galaxies (ETGs), based on a joint lensing and dynamical analysis, and on stellar population synthesis models, for a sample of 55 lens ETGs identified by the Sloan Lens Advanced Camera for Surveys (SLACS). We construct axisymmetric dynamical models based on…
Indirect Evidence for Escaping Ionizing Photons in Local Lyman Break Galaxy Analogs
Heckman, Timothy M.; Leitherer, Claus; Alexandroff, Rachael M. +2 more
A population of early star-forming galaxies is the leading candidate for the re-ionization of the universe. It is still unclear, however, what conditions and physical processes would enable a significant fraction of the ionizing (Lyman continuum) photons to escape from these gas-rich galaxies. In this paper we present the results of the analysis o…
Multiple stellar populations in Magellanic Cloud clusters - III. The first evidence of an extended main sequence turn-off in a young cluster: NGC 1856
Milone, A. P.; Marino, A. F.; Bedin, L. R. +7 more
Recent studies have shown that the extended main-sequence turn-off (eMSTO) is a common feature of intermediate-age star clusters in the Magellanic Clouds (MCs). The most simple explanation is that these stellar systems harbour multiple generations of stars with an age difference of a few hundred million years. However, while an eMSTO has been dete…