The alpha -element abundances in the most oxygen-poor planetary nebula PNG 135.9+55.9
We present extensive new spectroscopy and imaging of PNG 135.9+55.9. We use these data as constraints to photoionization models to derive limits on the oxygen abundance. We find that PNG 135.9+55.9 has an oxygen abundance less than 1/50 of the solar value. Our models favour a value of 12 + log O/H between 5.8 and 6.5 dex, confirming that PNG 135.9
Richer, M. G. et al.
Fecha de publicación:
12
2002