activity
19972006
collaborators

7 papers

astro-ph2006

The nature of the metal-rich thick disk

T. Bensby, A. R. Zenn, M. S. Oey +1

We have traced the Galactic thick disk to its, to date, highest metallicities. Based on high-resolution spectroscopic observations of 187 F and G dwarf stars that kinematically can…

astro-ph2006

The origin and chemical evolution of carbon in the Galactic thin and thick disks

T. Bensby, S. Feltzing

[ABRIDGED] In order to trace the origin and evolution of carbon in the Galactic disk we have determined carbon abundances in 51 nearby F and G dwarf stars. The sample is divided in…

astro-ph2005

Carbon Abundances in the Galactic Thin and Thick Disks

T. Bensby, S. Feltzing

Although carbon is, together with oxygen and nitrogen, one of the most important elements in the study of galactic chemical evolution its production sites are still poorly known an…

astro-ph2004

On the transmission- to reprocessing-dominated spectral state transitions in Seyfert 2 galaxies

M. Guainazzi, A. C. Fabian, K. Iwasawa +2

We present Chandra and XMM-Newton observations of a small sample (11 objects) of optically-selected Seyfert~2 galaxies, for which ASCA and BeppoSAX had suggested Compton-thick obsc…

astro-ph2004

A study of the 15 micron quasars in the ELAIS N1 and N2 fields

A. Afonso-Luis, E. Hatziminaoglou, I. Perez-Fournon +8

This paper discusses properties of the European Large Area ISO Survey 15 micron quasars and tries to establish a robust method of quasar selection for future use within the Spitzer…

astro-ph2003

Arakelian 564: An XMM-Newton view

C. Vignali, W. N. Brandt, Th. Boller +2

We report on two XMM-Newton observations of the bright narrow-line Seyfert 1 galaxy Ark 564 taken one year apart (2000 June and 2001 June). The 0.6-10 keV continuum is well describ…