EDP Sciences
Free access
Volume 369, Number 1, April I 2001
Page(s) L1 - L4
Section Letters
DOI http://dx.doi.org/10.1051/0004-6361:20010210

A&A 369, L1-L4 (2001)
DOI: 10.1051/0004-6361:20010210

Discovery of a bipolar and highly variable mass outflow from the symbiotic binary StH$\alpha$ 190

U. Munari1, 2, T. Tomov2, 3, B. F. Yudin4, P. M. Marrese1, 2, T. Zwitter5, R. G. Gratton6, G. Bonanno7, P. Bruno7, A. Calí7, R. U. Claudi6, R. Cosentino7, 8, S. Desidera6, G. Farisato6, G. Martorana1, G. Marino8, M. Rebeschini1, S. Scuderi7 and M. C. Timpanaro7

1  Osservatorio Astronomico di Padova, Sede di Asiago, 36032 Asiago (VI), Italy
2  Center of Studies and Activities for Space (CISAS "G. Colombo"), Uniersity of Padova, Italy
3  Center for Astronomy, Nicolaus Copernicus University, ul. Gagarina 11, 87100 Torun, Poland
4  Sternberg Astronomical Institute, Universitetskii pr. 13, Moscow 119899, Russia
5  Department of Physics, Univ. of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia
6  Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, 35122 Padova, Italy
7  Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy
8  Centro Galileo Galilei -CNAA, Calle Alvarez de Abreu 70, 38700 Santa Cruz de La Palma (TF), Spain

(Received 26 January 2001 / Accepted 6 February 2001 )

A highly and rapidly variable bipolar mass outflow from StH$\alpha$ 190 has been discovered, the first time in a yellow symbiotic star. Permitted emission lines are flanked by symmetrical jet features and multi-component P-Cyg profiles, with velocities up to 300 km s-1. Given the high orbital inclination of the binary, if the jets leave the system nearly perpendicular to the orbital plane, the de-projected velocity equals or exceeds the escape velocity (1000 km s-1). StH$\alpha$ 190 looks quite peculiar in many other respects: the hot component is an O-type sub-dwarf without an accretion disk or a veiling nebular continuum and the cool component is a G7 III star rotating at a spectacular 105 km s-1, unseen by a large margin in field G giants.

Key words: binaries: symbiotic -- stars: individual: StH$\alpha$ 190 -- interstellar medium: jets and outflows

Offprint request: U. Munari, ulisse@ulisse.pd.astro.it

SIMBAD Objects

© ESO 2001