Search Publications
Accretion rates of 42 nova-like stars with IUE and Gaia data
Selvelli, Pierluigi; Gilmozzi, Roberto
We analyzed more than 700 ultraviolet spectra of 45 nova-like stars (NLs) observed with the International Ultraviolet Explorer (IUE) satellite, obtaining reliable data for 42 of them. Combining these with the distances from the Gaia Early Data Release 3 (EDR3) and with results from the literature, for each object we determined the reddening E…
Runaway BN supergiant star HD 93840: Progenitor of an imminent core-collapse supernova above the Galactic plane
Butler, K.; Weßmayer, D.; Przybilla, N. +1 more
We present a quantitative spectral analysis of the extreme nitrogen-enhanced supergiant HD 93840 (BN1 Ib) at an intermediate galactic latitude. Based on an optical high-resolution spectrum and complementary ultraviolet and infrared (spectro-)photometry, in addition to Gaia data, we carried out a full characterisation of the star's properties. We u…
Probing the inner Galactic halo with blue horizontal-branch stars. Gaia DR3-based catalogue with atmospheric and stellar parameters
Geier, S.; Heber, U.; Pelisoli, I. +4 more
Context. Stars that are found on the blue horizontal-branch (BHB) evolved from low-mass stars that have completed their core hydrogen-burning main sequence (MS) stage and undergone the helium flash at the end of their red giant phase. Hence, they are very old objects that can be used as markers in studying galactic structure and formation history.…
Quantitative spectroscopy of multiple OB stars: I. The quadruple system HD 37061 at the centre of Messier 43
Przybilla, N.; Aschenbrenner, P.
Context. The majority of massive stars are located in binary or multiple star systems. Compared to single stars, these objects pose additional challenges to quantitative analyses based on model atmospheres. In particular, little information is currently available on the chemical composition of such systems. Aims. The members of the quadruple star …
A benchmark rapidly oscillating chemically peculiar (roAp) star: α Cir
Kallinger, T.; Stassun, K. G.; Kuschnig, R. +1 more
Context. The brightest chemically peculiar magnetic (mCP) star, α Cir, is also pulsating. Precise photometric and spectroscopic data, preferably with a long time base, are needed to investigate its evolutionary aspects as well. The present investigation of α Cir offers a space-based high-precision photometry study with high time resolution, coveri…
Hot subdwarf wind models with accurate abundances. II. Helium-dominated merger products CD-46 8926 and CD-51 11879
Krtička, J.; Vučković, M.; Janík, J. +3 more
Context. Helium-dominated subdwarfs are core helium burning stars stripped of their envelope. The nuclear evolution of these stars alters surface abundances. Modified abundances impact the strength of the stellar wind.
Aims: We aim to understand the influence of modified surface abundances on the strength of the stellar wind in the helium-dom…
Current and secular accretion rates of EX Hydrae
Beuermann, K.; Reinsch, K.
We report an observed accretion rate of Ṁ1 = (3.86 ± 0.60) × 10−11 M⊙ yr−1 for the white dwarf in the short-period, intermediate polar