Search Publications
A joint mid-infrared spectroscopic and X-ray imaging investigation of LINER galaxies
Dudik, R. P.; Satyapal, S.; Sambruna, R. M.
We present a comprehensive comparative high resolution mid-IR spectroscopic and X-ray imaging investigation of LINERs using archival observations from the ISO-SWS and the Chandra Advanced CCD Imaging Spectrometer. Although the sample is heterogenous and incomplete, this is the first comprehensive study of the mid-infrared fine structure line emiss…
A phase-dependent absorption line in the spectrum of the X-ray pulsar RX J0720.4-3125
Haberl, F.; Burwitz, V.; Trümper, J. +1 more
The XMM-Newton spectra of the isolated neutron star
The metal content of the bulge globular cluster NGC 6528
Minniti, D.; Pasquini, L.; Zoccali, M. +7 more
High resolution spectra of five stars in the bulge globular cluster NGC 6528 were obtained at the 8m VLT UT2-Kueyen telescope with the UVES spectrograph. Out of the five stars, two of them showed evidence of binarity. The target stars belong to the horizontal and red giant branch stages, at 4000 < Tefflt; 4800 K. Multiband V, I, J, H…
Modeling an X-ray flare on Proxima Centauri: Evidence of two flaring loop components and of two heating mechanisms at work
Audard, M.; Güdel, M.; Peres, G. +1 more
We model in detail a flare observed on Proxima Centauri with the EPIC-PN on board XMM-Newton at high statistics and high time resolution and coverage. Time-dependent hydrodynamic loop modeling is used to describe the rise and peak of the light curve, and a large fraction of the decay, including its change of slope and a secondary maximum, over mor…
Ionized gas kinematics and massive star formation in NGC 1530
Knapen, J. H.; Relaño, M.; Beckman, J. E. +1 more
We present emission line mapping of the strongly barred galaxy NGC 1530 obtained using Fabry-Pérot interferometry in H\alpha, at significantly enhanced angular resolution compared with previously published studies. The main point of the work is to examine in detail the non-circular components of the velocity field of the gas, presumably induced by…
The distance to the Pleiades from orbital solution of the double-lined eclipsing binary HD 23642
Munari, U.; Soubiran, C.; Siviero, A. +3 more
Combining precise B, V photometry and radial velocities, we have been able to derive a firm orbital solution and accurate physical parameters for the newly discovered eclipsing binary HD 23642 in the Pleiades open cluster. The resulting distance to the binary and therefore to the cluster is 132 ± 2 pc. This closely confirms the distance modulus ob…
The high energy emission line spectrum of NGC 1068
Bianchi, S.; Guainazzi, M.; Molendi, S. +1 more
We present and discuss the high energy (E>4 keV) XMM-Newton spectrum of the Seyfert 2 galaxy, NGC 1068. Possible evidence for flux variability in both the neutral and ionized reflectors with respect to a BeppoSAX observation taken 3.5 years before is found. Several Fe and Ni emission lines, from both neutral and highly ionized material, are det…
The Luminosity-Metallicity relation of distant luminous infrared galaxies
Elbaz, D.; Flores, H.; Cesarsky, C. J. +3 more
One hundred and five 15 \mum-selected objects in three ISO (Infrared Space Observatory) deep survey fields (CFRS 3h, UDSR and UDSF) are studied on the basis of their high-quality optical spectra with resolution R>1000 from VLT/FORS2. ∼92 objects (88%) have secure redshifts, ranging from 0 to 1.16 with a median value of z_med=0.587. <…
The ubiquitous nature of the horizontal branch second U-jump. A link with the Blue Hook scenario?
Recio-Blanco, A.; De Angeli, F.; Momany, Y. +5 more
In a previous paper we reported on a discontinuity in the extreme horizontal branch (EHB) of the Galactic globular cluster NGC 6752, which we called the second U-jump. This feature was attributed to a combination of post zero-age horizontal branch evolution and diffusion effects. In this follow-up study we analyze other EHB clusters and show that …
Multi-site, multi-technique survey of γ Doradus candidates. I. Spectroscopic results for 59 stars
Poretti, E.; Garrido, R.; Rodríguez, E. +14 more
We present the first results of a 2-year high-resolution spectroscopy campaign of 59 candidate γ Doradus stars which were mainly discovered from the HIPPARCOS astrometric mission. More than 60% of the stars present line profile variations which can be interpreted as due to pulsation related to γ Doradus stars. For all stars we also derived the pro…