AN EXTENSIVE STUDY OF PLANETARY-NEBULAE IN THE GALACTIC BULGE .5. MONTE-CARLO SIMULATIONS OF AN OBSERVED SAMPLE

We have analyzed the population of Galactic bulge planetary nebulae (G BPN) by means of Monte-Carlo methods. Statistical tests were used to c ompare observed histograms with simulated distributions of radio fluxe s, angular diameters, surface brightnesses and nebular ionized masses. We have shown how selection effects operate in observed diagrams and alter our understanding of the GBPN population: for example, the obser ved central star mass distribution is biased upwards with respect to t he intrinsic one. The present observational constraints allow a large number of solutions, and it is essential to measure the nebular expans ion velocities for a better understanding of the GBPN population. Stil l, all the accepted solutions correspond to a very narrow central star mass distribution, centered on a value not larger than 0.6 M.. Incide ntally, we have found that, in the synthetic populations which are com patible with the observations, there is a large proportion of density bounded nebulae. This is an important result for studies of the HR dia gram for central stars.