Search Publications
Charge-transfer induced EUV and soft X-ray emissions in the heliosphere
Lallement, R.; Izmodenov, V.; Quémerais, E. +4 more
Aims.We study the EUV/soft X-ray emission generated by charge transfer between solar wind heavy ions and interstellar neutral atoms and variations of the X-ray intensities and spectra with the line of sight direction, the observer location, the solar cycle phase and the solar wind anisotropies, and a temporary enhancement of the solar wind similar…
IGR J17544-2619 : a new supergiant fast X-ray transient revealed by optical/infrared observations
Chaty, S.; Negueruela, I.; Pellizza, L. J.
One of the most recent discoveries of the INTEGRAL observatory is the existence of a previously unknown population of X-ray sources in the inner arms of the Galaxy.
Large amplitude oscillation of a polar crown filament in the pre-eruption phase
Isobe, H.; Tripathi, D.
Aims.We report observation of a large-amplitude filament oscillation followed by an eruption. This is used to probe the pre-eruption condition and the trigger mechanism of solar eruptions.Methods.We used the EUV images from the Extreme-Ultraviolet Imaging Telescope on board SOHO satellite and the Hα images from the Flare Monitoring Telescope at Hi…
Structure and scaling of the entropy in nearby galaxy clusters
Arnaud, M.; Pointecouteau, E.; Pratt, G. W.
Using XMM-Newton observations, we investigate the scaling and structural properties of the ICM entropy in a sample of 10 nearby (z < 0.2) morphologically relaxed galaxy clusters in the temperature range 2-9 keV. We derive the local entropy-temperature (S{-}T) relation at R = 0.1, 0.2, 0.3 and 0.5R200. The logarithmic slope of the rel…
The radio structure of radio-quiet quasars
Falcke, H.; Hüttemeister, S.; Leipski, C. +1 more
Aims.We investigate the radio emitting structures of radio-quiet active galactic nuclei with an emphasis on radio-quiet quasars to study their connection to Seyfert galaxies.
Methods: .We present and analyse high-sensitivity VLA radio continuum images of 14 radio-quiet quasars and six Seyfert galaxies.
Results: .Many of the low redshift ra…
X-ray properties in massive galaxy clusters: XMM-Newton observations of the REFLEX-DXL sample
Zhang, Y. -Y.; Finoguenov, A.; Böhringer, H. +5 more
We selected an unbiased, flux-limited and almost volume-complete sample of 13 distant, X-ray luminous (DXL, z∼ 0.3) clusters and one supplementary cluster at z=0.2578 from the REFLEX Survey (the REFLEX-DXL sample). We performed a detailed study to explore their X-ray properties using XMM-Newton observations. Based on the precise radial distributio…
The host galaxy/AGN connection in nearby early-type galaxies. Is there a miniature radio-galaxy in every "core" galaxy?
Capetti, A.; Balmaverde, B.
This is the second of a series of three papers exploring the connection between the multiwavelength properties of AGN in nearby early-type galaxies and the characteristics of their hosts. We selected two samples with 5 GHz VLA radio flux measurements down to 1 mJy, reaching levels of radio luminosity as low as 1036 erg s-1. I…
An updated survey of globular clusters in M 31. I. Classification and radial velocity for 76 candidate clusters
Bellazzini, M.; Galleti, S.; Federici, L. +2 more
Aims.We present the first results of a large spectroscopic survey of globular clusters and candidate globular clusters in the nearby M 31 galaxy. The survey is aimed at the classification of known candidate M 31 clusters and at the study of their kinematic properties.
Methods: .We obtained low-resolution spectroscopy (λ/Δλ ≃ 800-1300) for 133 …
Cosmic evolution of the galaxy's mass and luminosity functions by morphological type from multi-wavelength data in the CDF-South
Berta, S.; Rodighiero, G.; Hatziminaoglou, E. +7 more
Aims.We constrain the evolution of the galaxy mass and luminosity functions from the analysis of (public) multi-wavelength data in the Chandra Deep Field South (CDFS) area, obtained from GOODS and other projects, including very deep high-resolution imaging by HST/ACS.
Methods.Our reference catalogue of faint high-redshift galaxies, which we hav…
Evolution of magnetic fields and energetics of flares in active region 8210
Régnier, S.; Canfield, R. C.
To better understand eruptive events in the solar corona, we combine sequences of multi-wavelength observations and modelling of the coronal magnetic field of NOAA AR 8210, a highly flare-productive active region. From the photosphere to the corona, the observations give us information about the motion of magnetic elements (photospheric magnetogra…