Search Publications
Physical parameters and ±0.2% parallax of the detached eclipsing binary V923 Scorpii
Kervella, P.; Mérand, A.; Rucinski, S. M. +10 more
Context. V923 Sco is a bright (V = 5.91), nearby (π = 15.46 ± 0.40 mas) southern eclipsing binary. Because both components are slow rotators, the minimum masses of the components are known with 0.2% precision from spectroscopy. The system seems ideal for very precise mass, radius, and luminosity determinations and, owing to its proximity and long …
V902 Monocerotis: A likely disc-accreting intermediate polar
Mukai, K.; Schwope, A. D.; Traulsen, I. +2 more
Aims: We aim to confirm whether the eclipsing cataclysmic variable (CV) V902 Mon is an intermediate polar (IP), to characterise its X-ray spectrum and flux, and to refine its orbital ephemeris and spin period.
Methods: We performed spectrographic observations of V902 Mon in 2016 with the 2.2 m Calar Alto telescope, and X-ray photometry a…
Hot star extension to the Hubble Space Telescope stellar spectral library
Worthey, Guy; Khan, Islam
Context. Libraries of stellar spectra find many uses in astrophysics, from photometric calibration to stellar population synthesis.
Aims: We present low resolution spectra of 40 stars from 0.2 µm (ultraviolet) to 1.0 µm (near infrared) with excellent fluxing. The stars include normal O-type stars, helium-burning stars, and post-as…
Interstellar polarization and extinction towards the young open cluster NGC 1502
Paunzen, E.; Topasna, G. A.; Kaltcheva, N. T.
Aims: NGC 1502 is located at the periphery of the Cam OB1 association and probably within the Orion Spur, with published distance estimates varying between 0.7 and 1.5 kpc. We combine new polarimetric observations and existing uvbyβ and UBV photometries to provide new estimates of the cluster's parameters.
Methods: We present new multi-w…
Non-equilibrium ionization by a periodic electron beam. II. Synthetic Si IV and O IV transition region spectra
Dudík, Jaroslav; Dzifčáková, Elena
Context. Transition region (TR) spectra typically show the Si IV 1402.8 Å line to be enhanced by a factor of 5 or more compared to the neighboring O IV 1401.2 Å, contrary to predictions of ionization equilibrium models and the Maxwellian distribution of particle energies. Non-equilibrium effects in TR spectra are therefore expected.
Aims: To …
High-J CO emission spatial distribution and excitation in the Orion Bar
Abergel, A.; Parikka, A.; Habart, E. +2 more
Context. With Herschel, we can for the first time observe a wealth of high-J CO lines in the interstellar medium with a high angular resolution. These lines are specifically useful for tracing the warm and dense gas and are therefore very appropriate for a study of strongly irradiated dense photodissocation regions (PDRs).
Aims: We characteri…
Well-defined EUV wave associated with a CME-driven shock
Selhorst, C. L.; Cunha-Silva, R. D.; Fernandes, F. C. R. +1 more
Aims: We report on a well-defined EUV wave observed by the Extreme Ultraviolet Imager (EUVI) on board the Solar Terrestrial Relations Observatory (STEREO) and the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO). The event was accompanied by a shock wave driven by a halo CME observed by the Large Angle and Spec…
The first study of 54 new eccentric eclipsing binaries in our Galaxy
White, G. J.; Wolf, M.; Jelínek, M. +12 more
We present an analysis of the apsidal motion and light curve parameters of 54 never-before-studied galactic Algol-type binaries. This is the first analysis of such a large sample of eccentric eclipsing binaries in our Galaxy, and has enabled us to identify several systems that are worthy of further study. Bringing together data from various databa…
The global sphere reconstruction (GSR). Demonstrating an independent implementation of the astrometric core solution for Gaia
Lattanzi, M. G.; Messineo, R.; Abbas, U. +6 more
Context. The Gaia ESA mission will estimate the astrometric and physical data of more than one billion objects, providing the largest and most precise catalog of absolute astrometry in the history of astronomy. The core of this process, the so-called global sphere reconstruction, is represented by the reduction of a subset of these objects which w…
The HP2 Survey. IV. The Pipe nebula: Effective dust temperatures in dense cores
Alves, João; Forbrich, Jan; Lada, Charles J. +3 more
Multi-wavelength observations in the sub-millimeter regime provide information on the distribution of both the dust column density and the effective dust temperature in molecular clouds. In this study, we created high-resolution and high-dynamic-range maps of the Pipe nebula region and explored the value of dust-temperature measurements in particu…