Luis F. Rodríguez,1,2 Alejandro Báez–Rubio,1,3 and Anatoly S. Miroshnichenko4
1 Centro de Radiostronomía y Astrofísica, Universidad Nacional Autónoma de México, Apdo. Postal 3–72, (Xangari), 58089 Morelia, Michoacán, México. (l.rodriguez@crya.unam.mx).
2 Astronomy Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
3 Centro de Astrobiología (CSIC/INTA), Ctra. de Torrejón a Ajalvir km 4, 28850 Torrejón de Ardoz, Madrid, Spain. (baezra@cab.inta–csic.es).
4 Department of Physics and Astronomy, University of North Carolina, Greensboro, NC 27402 USA. (a_mirosh@uncg.edu).
]]> Received 2011 August 8.
RESUMEN
Las estrellas tipo FS CMa muestran espectros ópticos con líneas de emisión y fuertes excesos infrarrojos. Se sabe muy poco de sus características en ondas de radio. Hemos analizado datos de archivo del Very Large Array para buscar emisión de radiocontinuo en una muestra de ellas. Existen datos de buena calidad para siete de las aproximadamente 40 estrellas FS CMa conocidas. De estas siete estrellas, cinco resultan tener emisión de radio asociada. Dos de estas estrellas, CI Cam y MWC 300, han sido reportadas previamente en la literatura como emisoras de radio. Presentamos y discutimos brevemente la detección de las otras tres fuentes: FS CMa (el prototipo de la clase), AS 381, y MWC 922. La emisión de radio es muy probablemente libre–libre pero se requieren observaciones adicionales para caracterizarla mejor.
ABSTRACT
The FS CMa stars exhibit bright optical emission–line spectra and strong IR excesses. Very little is known of their radio characteristics. We analyzed archive Very Large Array data to search for radio continuum emission in a sample of them. There are good quality data for seven of the ~40 known FS CMa stars. Of these seven stars, five turn out to have associated radio emission. Two of these stars, CI Cam and MWC 300, have been previously reported in the literature as radio emitters. We present and briefly discuss the radio detection of the other three sources: FS CMa (the prototype of the class), AS 381, and MWC 922. The radio emission is most probably of a free–free nature but additional observations are required to better characterize it.
Key Words: radio continuum: stars — stars: individual (FS CMa, AS 381, MWC 922).
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