A complex bipolar outflow in the Wolf-Rayet BCDG He 2-10

We present results from multi-wavelength observations of the Wolf-Rayet (WR ) blue compact dwarf galaxy He 2-10. These observations include H alpha and optical red continuum imaging, high resolution H alpha spectroscopy, high resolution radio-continuum mapping at 4.80 and 8.64 GHz and ROSAT X-ray obs ervations. The deep H alpha images reveal that the galaxy is surrounded by a complex k iloparsec-scale bipolar superbubble centered on the most intense star formi ng knot. High-resolution spectroscopy of this feature indicates that it has a complex structure of possibly different kinematic components expanding a t velocities from less than or equal to 50 km s(-1) up to 250 km s(-1). The se kinds of outflows are likely to be produced by the mechanical action of stellar winds and supernova (SN) explosions in the intense starbursts that the galaxy hosts. This scenario is consistent with the finding of a steep o verall radio spectral index (alpha=-0.59) that confirms the presence of a l arge number of supernova remnants (similar to 3750) in the galaxy. The stud y of radio spectral index throughout the galaxy shows that the eastern part s have significantly steeper spectra. These radio regions have no counterpa rts in our H alpha or X-ray images. The X-ray emission extends to a similar scale as the H alpha emission. The extensions of the X-ray distribution towards northeast and southwest appear s to be well spatially correlated with the position of the bipolar lobes in dicating the hot gas is confined inside the bubbles. The comparison between the energetics of the outflows and the expected mech anical energy released by the supernovae and stellar winds indicates that t he large-scale expanding structures can be powered by the massive star popu lation of the galaxy and, therefore, can be considered a galactic wind. Est imates of the escape velocity of the galaxy indicate that part of the large scale outflows can escape the weak potential well of the galaxy, reinforci ng the possibility of a blowout in He 2-10.