Search Publications
A Spitzer View of Protoplanetary Disks in the γ Velorum Cluster
Jeffries, R. D.; Gutermuth, R.; Stauffer, J. +4 more
We present new Spitzer Space Telescope observations of stars in the young (~5 Myr) γ Velorum stellar cluster. Combining optical and 2MASS photometry, we have selected 579 stars as candidate members of the cluster. With the addition of the Spitzer mid-infrared data, we have identified five debris disks around A-type stars and five to six debris dis…
Gemini and Hubble Space Telescope Evidence for an Intermediate-Mass Black Hole in ω Centauri
Gebhardt, Karl; Noyola, Eva; Bergmann, Marcel
The globular cluster ω Centauri is one of the largest and most massive members of the galactic system. However, its classification as a globular cluster has been challenged making it a candidate for being the stripped core of an accreted dwarf galaxy; this together with the fact that it has one of the largest velocity dispersions for star clusters…
Jets in Coronal Holes: Hinode Observations and Three-dimensional Computer Modeling
Galsgaard, K.; Moreno-Insertis, F.; Ugarte-Urra, I.
Recent observations of coronal hole areas with the XRT and EIS instruments on board the Hinode satellite have shown with unprecedented detail the launching of fast, hot jets away from the solar surface. In some cases these events coincide with episodes of flux emergence from beneath the photosphere. In this Letter we show results of a three-dimens…
HESS very-high-energy gamma-ray sources without identified counterparts
Santangelo, A.; Ripken, J.; Carrigan, S. +141 more
Context: The detection of gamma rays in the very-high-energy (VHE) energy range (100 GeV-100 TeV) provides a direct view of the parent population of ultra-relativistic particles found in astrophysical sources. For this reason, VHE gamma rays are useful for understanding the underlying astrophysical processes in non-thermal sources.
Aims: We in…
Vigorous Star Formation with Low Efficiency in Massive Disk Galaxies at z = 1.5
Daddi, E.; Elbaz, D.; Morrison, G. +4 more
We present the first detection of molecular gas cooling CO emission lines from ordinary massive galaxies at z = 1.5. Two sources were observed with the IRAM Plateau de Bure Interferometer, selected to lie in the mass-star formation rate correlation at their redshift, thus being representative of massive high-z galaxies. Both sources were detected …
The Coincidence of Nuclear Star Clusters and Active Galactic Nuclei
Seth, Anil; Basu-Zych, Antara; Agüeros, Marcel +1 more
We study galaxies that host both nuclear star clusters and AGNs, implying the presence of a massive black hole. We select a sample of 176 galaxies with previously detected nuclear star clusters that range from ellipticals to late-type spirals. We search for AGNs in this sample using optical spectroscopy and archival radio and X-ray data. We find g…
Transiting exoplanets from the CoRoT space mission. II. CoRoT-Exo-2b: a transiting planet around an active G star
Mazeh, T.; Aigrain, S.; Alonso, R. +40 more
Context: The CoRoT mission, a pioneer in exoplanet searches from space, has completed its first 150 days of continuous observations of ~12 000 stars in the galactic plane. An analysis of the raw data identifies the most promising candidates and triggers the ground-based follow-up.
Aims: We report on the discovery of the transiting planet CoRoT…
On the star formation rate - brightest cluster relation: estimating the peak star formation rate in post-merger galaxies
Bastian, N.
We further the recent discussion on the relation between the star formation rate (SFR) of a galaxy and the luminosity of its brightest star cluster (SFR versus MbrightestV). We first show that the observed trend of SFR versus MbrightestV is due to the brightest cluster in a galaxy being preferentially yo…
Bars in Disk-dominated and Bulge-dominated Galaxies at z ~ 0: New Insights from ~3600 SDSS Galaxies
Jogee, Shardha; Barazza, Fabio D.; Marinova, Irina
We present a study of large-scale bars in the local universe, based on a large sample of 3692 galaxies, with 18.5 <= Mg < - 22.0 mag and redshift 0.01 <= z < 0.03, drawn from the Sloan Digitized Sky Survey. Our sample includes many galaxies that are disk-dominated and of late Hubble types. Both color cuts and Sérsic cuts yie…
Coupling photochemistry with haze formation in Titan's atmosphere, Part I: Model description
Coustenis, A.; Lavvas, P. P.; Vardavas, I. M.
We introduce a new 1D coupled Radiative/Convective-Photochemical-Microphysical model for a planetary atmosphere and apply it to Titan. The model incorporates detailed radiation transfer calculations for the description of the shortwave and longwave fluxes which provide the vertical structure of the radiation field and temperature profile. These ar…