2 MASS-LOSING CARBON STARS IN THE GALACTIC

Observations of two mass-losing carbon stars in the Galactic halo, IRA S 08546 + 1732 and 12560 + 1656, are presented, These objects were dis covered serendipitously, and stand out from the usual carbon stars st high galactic latitudes in that they have optical and IRAS colours con sistent with current mass-loss, New optical spectra, CO observations, and modelling of the spectral energy distribution and of the CO lines are presented, Luminosities are derived using a period-luminosity rela tion. From the dust modelling IRAS 085+6 +1732 is found to be al 20 kp c from the Sun (11.3 kpc from the Galactic plane) and has a mass-loss rate of 3.3 x 10(-6) M. yr(-1). From the CO non-detection we deduce th at it is probably oxygen-deficient, corroborating earlier work. IRAS 1 2560 + 1656 is found to be at 8.0 kpc from the Sun (7.8 kpc from the G alactic plane) and has a mass-loss rate of 1.3 x 10(-6) M. yr(-1). The detection of the (CO)-C-12 J=2-1 transition in the spectrum of IRAS 1 2560 + 1656 after an integration time of 10 h makes it probably the lo ngest (CO)-C-12 integration on a stellar object. The detection itself makes the star one of the most distant stellar objects detected in the CO line. The outflow velocity of 3.2 km s(-1) is very low, and the st ellar velocity is + 88 km s(-1) with respect to the LSR. Modelling of the CO line implies an oxygen abundance of 0.7 dex below solar. We exa mine existing data on the 'faint high-latitude carbon stars' and ident ify two additional distant, mass-losing, N-type AGE stars, The nature of halo carbon stars is discussed, and suggestions on how to find more mass-losing halo AGE stars are presented.