RADIO-CONTINUUM EMISSION FROM SHOCKED STELLAR
FLOWS IN LOW-MASS STARS
R.F. Gonzalez
(IAG-USP), J. Canto (IA-UNAM)
Young stars of low and
intermediate masses frequently show continuum emission in radio frequencies.
The observed flux densities and spectral indices indicate that, in most cases,
this emission is of thermal (free-free) origin and is produced in the powerful
stellar winds and/or bipolar outflows emanating from these stars. We present a
model in which the emission is produced by internal shocks formed in the flow
due to periodic variations of the velocity at injection. It is shown that the
free-free radio emission predicted by the model is in good agreement with those
observed in young stars of low and intermediate masses.
NUMERICAL
MODELING OF THE BIPOLAR OUTFLOWS OF ETA-CARINAE
R. F. Gonzalez
(IAG-USP), E. M. de Gouveia Dal Pino
(IAG-USP),
A. C. Raga (ICN-UNAM), P. F. Velazquez (ICN-UNAM)
We present preliminary
results of 2-D gas dynamics simulations of the formation and evolution of
Eta-Carinae bipolar humunculus structure. For this aim, we have employed a
version of the hydrodynamical adaptative grid-based code YGUAZU (developed by
Raga et al. 2000), assuming an interacting stellar wind scenario (e.g., Frank
et al. 1995) where a high velocity spherical stellar wind interacts with an
anisotropic low-speed outflow previously ejected.