Search Publications
A deep XMM-Newton serendipitous survey of a middle-latitude area. II. New deeper X-ray and optical observations
Caraveo, P. A.; de Luca, A.; Schirmer, M. +4 more
Context: The radio-quiet neutron star 1E1207.4-5209 has been the target of several XMM-Newton observations, with a total exposure of ~350 ks. The source is located at intermediate galactic latitude (b ∼ 10°), i.e. in a sky region with an extremely interesting mix of both galactic and extra-galactic X-ray sources.
Aims: The aim of our work is t…
GRS 1915+105: high-energy insights with SPI/INTEGRAL. Spectral analysis of the Comptonized emission
Jourdain, E.; Droulans, R.
Context: We report on results of nearly two years of INTEGRAL/SPI monitoring of the Galactic microquasar GRS 1915+105.
Aims: From September 2004 to May 2006, the source was observed twenty times with long (~100 ks) exposures. We present an analysis of the SPI data and focus on the description of the high-energy (>20 keV) output of the sourc…
Properties of magnetic elements in the quiet Sun using the marker-controlled watershed method
Zhang, J.; Yang, S. H.; Xie, Z. X. +2 more
Context: The quiet Sun is an important part of understanding the global magnetic properties of the Sun. A recently launched observation system, named HINODE, provides a lot of high-resolution images for studying the quiet Sun. Obviously, it is time-consuming to analyze these images by hand. It is desirable to develop a technique for recognizing ma…
Observation of a solar energetic particle event behind previous coronal mass ejection
Laitinen, T.; Kocharov, L.; Al-Sawad, A. +1 more
On 2001 October 19-21 the Energetic and Relativistic Nuclei and Electron (ERNE) instrument on the Solar and Heliospheric Observatory (SOHO) observed two gradual solar energetic particle (SEP) events separated by 15 h, in association with two X1.6/2B solar flares and halo coronal mass ejections (CMEs). The observational data suggest that the second…
Effective area calibration of the reflection grating spectrometers of XMM-Newton. II. X-ray spectroscopy of DA white dwarfs
Kaastra, J. S.; Lanz, T.; Hubeny, I. +1 more
Context: White dwarf spectra have been widely used as a calibration source for X-ray and EUV instruments. The in-flight effective area calibration of the reflection grating spectrometers (RGS) of XMM-Newton depend upon the availability of reliable calibration sources.
Aims: We investigate how well these white dwarf spectra can be used as stand…
Revisiting the optical interferometry observations of HR 4049
Quirrenbach, A.; Lopez, B.; Chesneau, O. +4 more
Aims: We present high spatial resolution observations in the mid-infrared of the dusty core of the binary system HR 4049.
Methods: We used the mid-infrared interferometer MIDI/VLTI with 40 m projected baselines. These observations provided two spectrally dispersed visibility curves at a spatial resolution of ~10 mas. Acquisition images and spe…
The hard X-ray view of bright infrared galaxies
Walter, R.; Cabral, N.
Aims: The synthesis of the cosmic X-ray background (CXB) requires a large population of Compton-thick active galactic nuclei that have not been detected so far. We probe whether bright infrared galaxies could harbor a population of Compton-thick nuclei and if they could contribute significantly.
Methods: We analyzed 112 Ms of INTEGRAL observat…
The new star forming site NGC 6334 IV (MM3)
Roth, M.; Gómez, M.; Persi, P. +1 more
Aims: The eastern part of the massive star forming region NGC 6334 IV is characterized by the presence of the millimeter continuum sources MM3, MM4, and the optically thin HII region G351.24+0.65. Here we study the star formation in this part of the cloud.
Methods: We imaged this region, here named NGC 6334 IV (MM3), at sub-arcsec resolution i…
Stellar populations in a standard ISOGAL field in the Galactic disc
Ganesh, S.; Omont, A.; Schultheis, M. +4 more
Aims: We identify the stellar populations (mostly red giants and young stars) detected in the ISOGAL survey at 7 and 15 µm towards a field (LN45) in the direction ℓ=-45, b=0.0.
Methods: The sources detected in the survey of the Galactic plane by the Infrared Space Observatory were characterised based on colour-colour and colour-magnitude…
Counterpart candidates to the unidentified Fermi source 0FGL J1848.6-0138
Combi, J. A.; Luque-Escamilla, P. L.; Martí, J. +3 more
Aims. We aim to contribute to the identification of the counterpart for one of the bright sources of gamma-rays in the catalogue obtained and released by the Fermi collaboration.
Methods: Our work is based on a extensive identification of sources from different wavelength catalogues and databases.
Results: As a first result, we report the …