Search Publications
Probing variability patterns of the Fe K line complex in bright nearby AGNs
Cappi, M.; Ponti, G.; Iwasawa, K. +5 more
Context: The unprecedented sensitivity of current X-ray telescopes allows the issue of the Fe K line complex variability patterns in bright, nearby AGNs to be addressed for the first time. These kinds of studies have the potential to map the accretion flow in the strong gravity regime of supermassive black holes.
Aims: We examine XMM-Newton ob…
Pulsations in the late-type Be star HD 50 209 detected by CoRoT
Auvergne, M.; Poretti, E.; Michel, E. +22 more
Context: The presence of pulsations in late-type Be stars is still a matter of controversy. It constitutes an important issue to establish the relationship between non-radial pulsations and the mass-loss mechanism in Be stars.
Aims: To contribute to this discussion, we analyse the photometric time series of the B8IVe star HD 50 209 observed by…
Broad-band properties of the hard X-ray cataclysmic variables IGR J00234+6141 and 1RXS J213344.1+510725
Mukai, K.; de Martino, D.; Terada, Y. +5 more
Context: A significant number of cataclysmic variables have been detected as hard X-ray sources in the INTEGRAL survey, most of them of the magnetic intermediate polar type.
Aims: We present a detailed X-ray broad-band study of two new sources, IGR J00234+6141 and 1RXS J213344.1+510725, that allow us to classify them as secure members of the i…
Solar transition region above sunspots
Marsch, E.; Curdt, W.; Teriaca, L. +2 more
Aims: We study the transition region (TR) properties above sunspots and the surrounding plage regions, by analyzing several sunspot reference spectra obtained by the SUMER (Solar Ultraviolet Measurements of Emitted Radiation) instrument in March 1999 and November 2006.
Methods: We compare the SUMER spectra observed in the umbra, penumbra, plag…
Spectroscopic binaries among Hipparcos M giants,. I. Data, orbits, and intrinsic variations
Jorissen, A.; Pourbaix, D.; Udry, S. +4 more
Context: This paper is a follow-up on the vast effort to collect radial velocity data for stars belonging to the Hipparcos survey.
Aims: We aim at extending the orbital data available for binaries with M giant primaries. The data presented in this paper will be used in the companion papers of this series to (i) derive the binary frequency amon…
The isolated neutron star candidate 2XMM J104608.7-594306
Motch, C.; Treves, A.; Turolla, R. +2 more
Over the last decade, X-ray observations have revealed the existence of several classes of isolated neutron stars (INSs) which are radio-quiet or exhibit radio emission with properties much at variance with those of ordinary radio pulsars. The identification of new sources is crucial in order to understand the relations among the different classes…
On the differential rotation of CoRoT-2a
Strassmeier, K. G.; Hatzes, A. P.; Küker, M. +1 more
We apply a robust spot model to fit the light curve of CoRoT-2a. The spots are assumed to be long-living and each has its own rotation period. A model with three circular spots reproduces the basic features of the longitude-time spot coverage map. One of the spots exhibits a noticeably lower rotational frequency than the other two. From the rotati…
Long-term photometric monitoring with the Mercator telescope. Frequencies and multicolour amplitudes of γ Doradus stars
Uytterhoeven, K.; Drummond, R.; De Ridder, J. +21 more
Context: γ Dor stars are excellent targets for asteroseismology since the gravity modes present in these stars probe the deep stellar interiors. Mode identification will improve the knowledge of these stars considerably.
Aims: A selected group of γ Dor stars and some candidates were observed with the Mercator telescope to find and/or confirm t…
HST/ACS colour-magnitude diagrams of M 31 globular clusters
Cacciari, C.; Bellazzini, M.; Galleti, S. +3 more
Aims: With the aim of increasing the sample of M 31 clusters for which a colour-magnitude diagram is available, we searched the HST archive for ACS images containing objects included in the Revised Bologna Catalogue of M 31 globular clusters (RBC Version 3.5 available at: http://www.bo.astro.it/M31).
Methods: Sixty-three such objects were foun…
Young stars and protostellar cores near NGC 2023
Mookerjea, B.; Sandell, G.; Jarrett, T. H. +1 more
Context: We investigate the young (proto)stellar population in NGC 2023 and the L 1630 molecular cloud bordering the h ii region IC 434, using Spitzer IRAC and MIPS archive data, JCMT SCUBA imaging and spectroscopy as well as targeted BIMA observations of one of the Class 0 protostars, NGC 2023 MM 1.
Aims: We study the distribution of gas, dus…