Search Publications
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…
Intensity variations in EIT shutterless mode: Waves or flows?
Berghmans, D.; van Driel-Gesztelyi, L.; Poedts, S. +1 more
On 11 July 2001 an EIT shutterless campaign was conducted which provided 120 high-cadence (68 s) 304 Å images of the north eastern quarter of the Sun. The most interesting feature seen in the data is an off-limb half loop structure along which systematic intensity variations are seen which appear to propagate from the top of the loop towards its f…
HST/WFPC2 morphologies and color maps of distant luminous infrared galaxies
Pelat, D.; Flores, H.; Hammer, F. +2 more
Using HST/WFPC2 imaging in F606W (or F450W) and F814W filters, we obtained the color maps in observed frame for 36 distant (0.4 < z < 1.2) luminous infrared galaxies (LIRGs, LIR(8-1000 µm) ≥ 1011 L⊙), with average star formation rates of ∼100 M⊙ yr-1. Stars and compact sources are …
VLT spectroscopy of globular cluster systems. I. The photometric and spectroscopic data set
Saglia, R. P.; Thomas, D.; Bender, R. +6 more
We present Lick line-index measurements of extragalactic globular clusters in seven early-type galaxies (NGC 1380, 2434, 3115, 3379, 3585, 5846, and 7192) with different morphological types (E-S0) located in field and group/cluster environments. High-quality spectra were taken with the FORS2 instrument at ESO's Very Large Telescope. ∼50% of our da…