Search Publications
High resolution millimeter imaging of the proto-planetary nebula He 3-1475
Bachiller, R.; Forveille, T.; Cox, P. +2 more
We report high resolution (1 arcsec-2 arcsec) imaging of the CO 2-1 line and the millimeter continuum in the proto-planetary nebula He 3-1475. The observations reveal the presence of a massive (∼ 0.6 M⊙) envelope of molecular gas around the origin of the remarkable bipolar jet system seen in optical images with the HST. The CO kinematic…
Time-dependent ejection velocity model for the outflow of Hen 3-1475
Velázquez, P. F.; Raga, A. C.; Riera, A.
We present 2D axisymmetric and 3D numerical simulations of the proto-planetary nebula
An L0 dwarf companion in the brown dwarf desert, at 30 AU
Martín, E. L.; Ségransan, D.; Udry, S. +8 more
We present the discovery of an L0 companion to the nearby M1.5 dwarf G 239-25, at a projected distance of 31 AU. It is the faintest companion discovered so far in our adaptive optics survey of all known M dwarfs within 12 pc, and it lies at the stellar/substellar limit. Given the assumed age of the primary star, the companion is likely an extremel…
Late-type giant variables in NGC 6522, LMC and SMC. How do they differ?
Glass, I. S.; Schultheis, M.; Cioni, M. -R.
Complete samples of 2MASS stars in three fields of differing metallicities (and possibly differing age distributions) have been extracted and cross-correlated with MACHO and ISO data to determine their variability and mass-loss properties. In each MK histogram a fall-off in numbers is seen above the tip of the RGB. The luminosity of the…
Intrinsic absorbers in BL Lac objects: The XMM-Newton view
Page, M. J.; Branduardi-Raymont, G.; Blustin, A. J.
We present XMM-Newton observations of four BL Lac objects (
The global mass function of M 15
Pulone, L.; De Marchi, G.; Pasquali, A. +1 more
Data obtained with the NICMOS instrument on board the Hubble Space Telescope (HST) have been used to determine the H-band luminosity function (LF) and mass function (MF) of three stellar fields in the globular cluster M 15, located ∼7' from the cluster centre. The data confirm that the cluster MF has a characteristic mass of ∼0.3 M⊙, as…
The host galaxy of GRB 990712
Christensen, L.; Vreeswijk, P.; Gorosabel, J. +4 more
We present a comprehensive study of the z=0.43 host galaxy of
Constraining the very heavy elemental abundance peak in the chemically peculiar star χ Lupi, with new atomic data for Os II and Ir II
Leckrone, D. S.; Lundberg, H.; Wahlgren, G. M. +2 more
The determination of elemental abundances plays an important role in understanding the atmospheric processes that lead to anomalies in spectra of chemically peculiar stars. Ongoing study of the HgMn star χ Lupi has defined much of the elemental abundance distribution but progress is dependent upon the availability and accuracy of the atomic data. …
Mid-infrared selection of AGN
Siebenmorgen, R.; Schartel, N.; Haas, M. +6 more
Since a large fraction of active galactic nuclei (AGN) is missed in common UV-excess surveys and is even hard to find in radio, near-IR and X-ray surveys, we have used a new AGN selection technique which is expected to be not affected by extinction. Within the scientific verification of the ISOCAM Parallel Survey at 6.7 µm we have discovered…
A spectral and spatial analysis of η Carinae's diffuse X-ray emission using CHANDRA
Weis, K.; Bomans, D. J.; Davidson, K. +1 more
The luminous unstable star (star system) η Carinae is surrounded by an optically bright bipolar nebula, the Homunculus and a fainter but much larger nebula, the so-called outer ejecta. As images from the EINSTEIN and ROSAT satellites have shown, the outer ejecta is also visible in soft X-rays, while the central source is present in the harder X-ra…