Search Publications
First detection of rotational CO line emission in a red giant branch star
Groenewegen, M. A. T.
Context. For stars with initial masses below ~1 M⊙, the mass loss during the first red giant branch (RGB) phase dominates mass loss in the later asymptotic giant branch (AGB) phase. Nevertheless, mass loss on the RGB is still often parameterised by a simple Reimers law in stellar evolution models.
Aims: To try to detect CO thermal …
Analysis of X-ray spectral variability and black hole mass determination of the NLS1 galaxy Mrk 766
Titarchuk, L.; Gilli, R.; Giacchè, S.
We present an XMM-Newton time-resolved spectral analysis of the narrow-line Seyfert 1 galaxy Mrk 766. We analysed eight available observations taken between May 2000 and June 2005 with the EPIC-pn camera in order to investigate the X-ray spectral variability produced by changes in the mass accretion rate. The 0.2 - 10 keV spectra are extracted in …
Searching for highly obscured AGNs in the XMM-Newton serendipitous source catalog
Ranalli, P.; Georgantopoulos, I.; Lanzuisi, G. +9 more
The majority of active galactic nuclei (AGNs) are obscured by large amounts of absorbing material that makes them invisible at many wavelengths. X-rays, given their penetrating power, provide the most secure way for finding these AGNs. The XMM-Newton serendipitous source catalog, of which 3XMM-DR4 is the latest version, is the largest catalog of X…
A Gemini/GMOS study of the physical conditions and kinematics of the blue compact dwarf galaxy Mrk 996
Thuan, Trinh X.; Izotov, Yuri I.; Carrasco, Eleazar R. +1 more
Aims: We present an integral field spectroscopic study with the Gemini Multi-Object Spectrograph (GMOS) of the unusual blue compact dwarf (BCD) galaxy
Methods: We show through velocity and dispersion maps, emission-line intensity and ratio maps, and by a new technique of electron density limit imaging that the…
XMM-Newton observation of the Galactic supernova remnant W51C (G49.1-0.1)
Sasaki, Manami; Heinitz, Cornelia; Warth, Gabriele +1 more
Context. The supernova remnant (SNR)
Aims: Diffuse X-ray emission from the interior of the SNR can reveal element abundances in the different emission regions and she…
IGR J17488-2338: a newly discovered giant radio galaxy
Venturi, T.; Bird, A. J.; Ubertini, P. +4 more
We present the discovery of a large-scale radio structure associated with IGR J17488-2338, a source recently discovered by INTEGRAL and optically identified as a broad-line AGN at redshift 0.24. At low frequencies, the source properties are those of an intermediate-power FR II radio galaxy with a linear size of 1.4 Mpc. This new active galaxy is t…
The 2.35 year itch of Cygnus OB2 #9. III. X-ray and radio emission analysis based on 3D hydrodynamical modelling
Blomme, R.; Nazé, Y.; Pittard, J. M. +1 more
Context. The wind-wind collision in a massive star binary system leads to the generation of high temperature shocks that emit at X-ray wavelengths and, if particle acceleration is effective, may exhibit non-thermal radio emission. Cyg OB2#9 is one of a small number of massive star binary systems in this class.
Aims: X-ray and radio data recen…
New light on the multiple jets of CRL 618
Velázquez, P. F.; Raga, A. C.; Riera, A. +2 more
Context. Proto-planetary nebulae (pPNe) are thought to represent the transitory phase of the late stages of low- to intermediate-mass stars. Most pPNe show a bipolar or multipolar geometry. The process(es) that transforms the spherical asymptotic giant branch (AGB) ejecta into a bipolar/multipolar geometry is not known in detail. Interactions betw…
Expected number of supergiant fast X-ray transients in the Milky Way
Santangelo, A.; Ducci, L.; Romano, P. +2 more
In the past fifteen years a new generation of X-ray satellites led to the discovery of a subclass of high-mass X-ray binaries (HMXBs) with supergiant companions and a peculiar transient behaviour: supergiant fast X-ray transients (SFXTs). We calculate the expected number of Galactic SFXTs for the first time, using two different statistical approac…
Upper limits to interstellar NH+ and para-NH2- abundances. Herschel-HIFI observations towards Sgr B2 (M) and G10.6-0.4 (W31C)
Menten, K. M.; Persson, C. M.; Lis, D. C. +12 more
The understanding of interstellar nitrogen chemistry has improved significantly with recent results from the Herschel Space Observatory. To set even better constraints, we report here on deep searches for the NH+ ground state rotational transition J = 1.5-0.5 of the 2Π1/2 lower spin ladder, with fine-structure tran…