Search Publications
Recent star formation in the Lupus clouds as seen by Herschel
Hill, T.; White, G. J.; André, Ph. +26 more
We present a study of the star formation histories of the Lupus I, III, and IV clouds using the Herschel 70-500 µm maps obtained by the Herschel Gould Belt Survey Key Project. By combining the new Herschel data with the existing Spitzer catalog we obtained an unprecedented census of prestellar sources and young stellar objects in the Lupus c…
Convection-driven compaction as a possible origin of Enceladus's long wavelength topography
Besserer, J.; Nimmo, F.; Roberts, J. H. +1 more
The long wavelength surface topography of Enceladus shows depressions about 1 km in depth and ∼102 km wide. One possible cause of this topography is spatially variable amounts of compaction of an initially porous ice shell, driven by spatial variations in heat flux. Here, we show that the heat flux variations associated with convection …
Processes forming and sustaining Saturn's proton radiation belts
Krupp, N.; Roussos, E.; Paranicas, C. +2 more
Saturn's proton radiation belts extend over the orbits of several moons that split this region of intense radiation into several distinct belts. Understanding their distribution requires to understand how their particles are created and evolve. High-energy protons are thought to be dominantly produced by cosmic ray albedo neutron decay (CRAND). Th…
Photometric Determination of the Mass Accretion Rates of Pre-main-sequence Stars. IV. Recent Star Formation in NGC 602
Panagia, Nino; Beccari, Giacomo; De Marchi, Guido
We have studied the young stellar populations in NGC 602, in the Small Magellanic Cloud, using a novel method that we have developed to combine Hubble Space Telescope photometry in the V, I, and Hα bands. We have identified about 300 pre-main-sequence (PMS) stars, all of which are still undergoing active mass accretion, and have determined their p…
The spectroscopic evolution of the recurrent nova T Pyxidis during its 2011 outburst. II. The optically thin phase and the structure of the ejecta in recurrent novae
Sion, E. M.; Shore, S. N.; Starrfield, S. +4 more
Aims: We continue our study of the physical properties of the recurrent nova T Pyx, focussing on the structure of the ejecta in the nebular stage of expansion during the 2011 outburst.
Methods: The nova was observed contemporaneously with the Nordic Optical Telescope (NOT), at high resolution spectroscopic resolution (R ≈ 65 000) on 2011…
Carbon Monoxide in the Cold Debris of Supernova 1987A
Blommaert, J. A. D. L.; van Loon, J. Th.; Fransson, C. +27 more
We report spectroscopic and imaging observations of rotational transitions of cold CO and SiO in the ejecta of SN1987A, the first such emission detected in a supernova remnant. In addition to line luminosities for the CO J = 1-0, 2-1, 6-5, and 7-6 transitions, we present upper limits for all other transitions up to J = 13-12, collectively measured…
Can the Differential Emission Measure Constrain the Timescale of Energy Deposition in the Corona?
Parenti, S.; Auchère, F.; Klimchuk, J. A. +2 more
In this paper, the ability of the Hinode/EIS instrument to detect radiative signatures of coronal heating is investigated. Recent observational studies of active region cores suggest that both the low and high frequency heating mechanisms are consistent with observations. Distinguishing between these possibilities is important for identifying the …
Unveiling new members in five nearby young moving groups
Ábrahám, P.; Kóspál, Á.; Kiss, L. L. +5 more
In the past decade many kinematic groups of young stars (<100 Myr) were discovered in the solar neighbourhood. Since the most interesting period of planet formation overlaps with the age of these groups, their well dated members are attractive targets for exoplanet searches by direct imaging. We combined astrometric, photometric and X-ray data,…
Bottom-heavy initial mass function in a nearby compact l{star} galaxy.
La Barbera, F.; Vazdekis, A.; Ferreras, I. +4 more
We present orbit-based dynamical models and stellar population analysis of Sloan Digital Sky Survey J151741.75-004217.6, a low-redshift (z = 0.116) early-type galaxy (ETG) which, for its moderate luminosity, has an exceptionally high velocity dispersion. We aim to determine the central black hole (BH) mass (M•), the i-band stellar mass-…
AKARI North Ecliptic Pole Deep Survey. Revision of the catalogue via a new image analysis
Małek, K.; Ohyama, Y.; Pearson, C. +10 more
Context. We present the revised near- to mid-infrared catalogue of the AKARI North Ecliptic Pole deep survey. The survey has the unique advantage of continuous filter coverage from 2 to 24 µm over nine photometric bands, but the initial version of the survey catalogue leaves room for improvement in the image analysis stage; the original imag…