Abundances of Recently Discovered Planetary Nebulae

نویسندگان

  • A. V. Escudero
  • R. D. D. Costa
چکیده

In this work we report spectrophotometric observations of a planetary nebula sample towards the galac-tic bulge. A total of 45 PNe was observed and their physical parameters (electron density and temperature) were derived. Ionic abundances were calculated using a three-level atom model and abundances were derived through ionisation correction factors. Results show low abundance objects at high galactic latitudes, indicating a possible vertical gradient inside the bulge. A few objects with low N/O ratio were found, which could originated from old, low mass progenitors.

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تاریخ انتشار 2001