The identification of PM 1-322 as a new young high-density planetary nebulae

We report spectroscopic observations of a new planetary nebula PM 1-322, which has not yet been identified. This object was found during a northern survey of post-AGB and planetary nebulae candidates selected from García-Lario et al. (1997, A&AS, 126, 479) and Preite-Martinez (1988, A&AS, 76, 317). Here we present the main spectroscopic features including a list of the intensities of the identified emission lines. The main spectral characteristic of PM 1-322 is the presence of a very strong [O iii] λ4363 emission line (I[OIII]4363/Hβ ≃ 120) indicating high electron densities (log N_e > 6.0). A comparison with similar objects strongly suggests that PM 1-322 is a very young planetary nebula, although the posibility of a symbiotic nature can not be ruled out.

Based on observations collected at the Centro Astronomico Hispano Aleman (CAHA) at Calar Alto, operated jointly by the Max-Planck Institut für Astronomie and the Instituto de Astrofísica de Andalucía (CSIC).