Search Publications
High-resolution spectral analysis of unevenly spaced data using a regularization approach
Seghouani, N.
The problem of estimating the power spectrum of unevenly spaced time series is considered. Indeed, this problem is quite common in ground-based astronomy, and the use of classical methods leads to aliased frequency detection. Moreover, the spectral resolution is limited by the observation time (Shannon-Nyquist law). We propose a regularized method…
Compton thick absorber in type 1 quasar 3C 345 revealed by Suzaku and Swift/BAT
Eguchi, Satoshi
The archival data of 3C 345, a type 1 quasar at z = 0.5928, obtained with Suzaku and Swift/BAT are analysed. Though previous studies of this source applied only a simple broken power-law model, a heavily obscuring material is found to be required by considering Akaike information criteria. The application of the numerical torus model by Murphy &am…
On the nature of the candidate T-Tauri star V501 Aurigae★
Neuhäuser, R.; Ginski, C.; Mugrauer, M. +18 more
We report new multicolour photometry and high-resolution spectroscopic observations of the long-period variable V501 Aur, previously considered to be a weak-lined T-Tauri star belonging to the Taurus-Auriga star-forming region. The spectroscopic observations reveal that V501 Aur is a single-lined spectroscopic binary system with a 68.8-d orbital p…
A (likely) X-ray jet from NGC6217 observed by XMM-Newton
Larsson, Josefin; Falocco, Serena; Nandi, Sumana
NGC6217 is a nearby spiral galaxy with a starburst region near its centre. Evidence for a low-luminosity Active Galactic Nucleus (AGN) in its core has also been found in optical spectra. Intriguingly, X-ray observations by ROSAT revealed three knots aligned with the galaxy centre, resembling a jet structure. This paper presents a study of XMM-Newt…
Study of a large arched structure of interstellar H I in the southern Milky Way
Olano, C. A.
We have revisited the sky region delimited by 290° < l < 320° and 3° < b < 17°, which includes a large arc of neutral hydrogen (H I), and extended the study region using the Leiden-Argentine-Bonn H I survey. The H I arc is almost an open downward semi-circumference of ≈10° of radius, with the symmetry axis perpendicular to the Galactic…
The 5 Gyr evolution of sub-M* galaxies
Yang, Y.; Flores, H.; Hammer, F. +3 more
We gathered two complete samples of MAB(r) < -18 (Mstar > 109 M⊙) galaxies, which are representative of the present-day galaxies and their counterparts at 5 Gyr ago. We analysed their 2D luminosity profiles and carefully decomposed them into bulges, bars and discs. This was done in a very consisten…
Editorial: Comets: A new vision after Rosetta and Philae
Taylor, Matt G. G. T.
Effects of the convective field on weakly outgassing comets
Galand, M.; Beth, A.
By applying a kinetic approach, we have developed two models in order to assess the influence of one main driver of plasma acceleration, the convective electric field, on the cometary ion distribution at 67P/Churyumov-Gerasimenko (67P/C-G). This electric field is carried by the solar wind and corresponds to the acceleration undergone by cometary i…