THE OUTFLOW STRUCTURE OF NGC-6537

We present high and low resolution spectroscopy and narrow-band imagin g of the unusual bipolar outflow source NGC 6537. As a consequence, we are able for the first time to construct large scale velocity maps of this source; note the presence of strongly variable core outflow dens ities, rising to a peak value n(e) similar to 1.7 10(4) cm(-3); find e vidence for substantial core ionization stratification; and demonstrat e the presence of a spatially extended, intermediate velocity wind ext ending over a range Delta v(1) similar or equal to 700 km s(-1), toget her with a more tightly constrained component having Delta v similar o r equal to 4400 km s(-1). This latter wind appears co-spatial with the slower, higher intensity core emission, and may be responsible for dr iving denser clumps of material to a typical velocity v(exp) similar t o 18 km s(-1). Temperatures appear to vary significantly over the core , from a peak value T-e similar or equal to 1.0 10(4) K close to the n ucleus, to similar or equal to 0.9 10(4) K for projected radial offset s of 5 '', whilst extinction is more or less constant, yielding a mean estimate A(v) similar or equal to 3.4 +/- 0.2 mag. Application of a s hock outflow model suggests that most of these features are readily ex plained providing wind mass-loss rates are of order M similar to 6 10 (-8)-6 10(-7) M. yr(-1), and the flow is strongly collimated by an int erior disk. In particular, we are able to provide excellent simulation s for both the complex kinematics, and unusual bipolar configuration.