Search Publications
Presence of dust with a UV bump in massive, star-forming galaxies at 1 < z < 2.5
Pannella, M.; Noll, S.; Pierini, D. +1 more
Aims:Fundamental properties of the extinction curve, like the slope in the rest-frame ultraviolet (UV) and the presence/absence of a broad absorption excess centred at 2175 Å (the UV bump), are investigated for a sample of 108 massive, star-forming galaxies at 1 < z < 2.5, selected from the FDF Spectroscopic Survey, the K20 survey, and the G…
Hard X-ray flares in IGR J08408-4503 unveil clumpy stellar winds
Masetti, N.; Walter, R.; Produit, N. +2 more
Context: A 1000-s flare from a new hard X-ray transient,
A study of the β Cephei star γ Pegasi: binarity, magnetic field, rotation, and pulsations
Butkovskaya, V. V.; Plachinda, S. I.
Aims:We provide observational material to study the magnetic field variability of the classical
Methods: The observations were carried out in the He I 6678 line in the course of 23 observing nights from 1997 to 2005 with using the Coudé spectrograph in spectropolarimetric mode at the…
A refined analysis of the remarkable Bp star HR 6000
Hubrig, S.; Castelli, F.
Aims:UVES spectra of the very young (∼ 107 years) peculiar B-type star HR 6000 were analyzed in the near-UV and visual spectral regions (3050-9460 Å) with the aim of extending to other spectral ranges the study made previously in the UV using IUE spectra.
Methods: Stellar parameters T_eff = 12 850 K, log g = 4.10, and ξ=0 km s-…
The HeII Fowler lines and the OIII and NIII Bowen fluorescence lines in the symbiotic nova RR Telescopii
Danziger, J.; Bonifacio, P.; Selvelli, P.
Aims:A detailed study of the O III and N III Bowen lines in the spectrum of RR Tel.
Methods: Absolute intensities for the He II, O III, and N III emission lines have been obtained from STIS, UVES, FEROS and IUE data, after re-calibration of UVES and FEROS on the STIS scale.
Results: A new measure of reddening (E(B-V) 0.00) has b…
The secrets of T Pyxidis. I. UV observations
Selvelli, P.; Gilmozzi, R.
Aims:We study the UV spectral behavior of the recurrent nova T Pyx during 16 years of <sl>IUE observations.</sl>
Methods: We examined both the <sl>IUE line-by-line images and the extracted spectra in order to understand the reality and the origin of the observed spectral variations. We compare different extraction methods and…
Atomic data for radioactive elements Ra I, Ra II, Ac I and Ac II and application to their detection in HD 101065 and HR 465
Quinet, P.; Fivet, V.; Yushchenko, A. V. +3 more
Radiative data for transitions of astrophysical interest in radioactive elements Ra I, Ra II, Ac I and Ac II have been computed using a semi-empirical relativistic Hartree-Fock approach including core polarization effects. Most of the oscillator strengths reported in the present paper are new. A possible detection of radium (Ra II) and actinium (A…
HeI doubled emission lines from A0535+26 ≡ HDE 245770. A possible interpretation
Bernabei, S.; Rossi, C.; Giovannelli, F. +1 more
We report results of the spectroscopy for V725 Tau (HDE 245770, BD +26°883), commonly known as Flavia's star, which is the optical counterpart of the X-ray pulsar A0535+26, carried out at the 1.5 m Loiano telescope during one run of observations of this star spread over a period of years. The HeI emission lines clearly show doubling, which is good…
Gas and dust spectra of the D' type symbiotic star HD 330036
Ciroi, S.; Rafanelli, P.; Angeloni, R. +1 more
Aims:We present a comprehensive and self-consistent modelling of the D' type symbiotic star (SS) HD 330036 from radio to UV.
Methods: Within a colliding-wind scenario, we analyse the continuum, line, and dust spectra by means of SUMA, a code that simulates the physical conditions of an emitting gaseous cloud under the coupled effect of ionisat…
Abundances of planetary nebula M 1-42
Pottasch, S. R.; Bernard-Salas, J.; Roellig, T. L.
The spectra of the planetary nebula M 1-42 is reanalysed using spectral measurements made in the mid-infrared with the Spitzer Space Telescope. The aim is to determine the chemical composition of this object. We also make use of ISO, IUE and ground based spectra. Abundances determined from the mid- and far-infrared lines, which are insensitive to …