The evolution of planetary nebulae VI. On the chemical composition of the metal-poor PN G135.9+55.9

Details The evolution of planetary nebulae VI. On the chemical composition of the metal-poor PN G135.9+55.9 The evolution of planetary nebulae VI. On the chemical composition of the metal-poor PN G135.9+55.9

2009-12-30

arxiv.org/abs/0912.5430v1

Astron. Astrophys. 486 (2008), A18

Astronomy and Astrophysics

Astrophysics

Solar and Stellar Astrophysics

10+6 pages, 6+5 figures, 5 tables, accepted for publication in A&A

Scientific paper

10.1051/0004-6361/200911796

The actual value of the oxygen abundance of the metal-poor planetary nebula PN G135.9+55.9 has frequently been debated in the literature. We wanted to clarify the situation by making an improved abundance determination based on a study that includes both new accurate observations and new models. We made observations using the method of integral field spectroscopy with the PMAS instrument, and also used ultraviolet observations that were measured with HST-STIS. In our interpretation of the reduced and calibrated spectrum we used for the first time, recent radiation hydrodynamic models, which were calculated with several setups of scaled values of mean Galactic disk planetary nebula metallicities. For evolved planetary nebulae, such as PN G135.9+55.9, it turns out that departures from thermal equilibrium can be significant, leading to much lower electron temperatures, hence weaker emission in collisionally excited lines. Based on our time-dependent hydrodynamic models and the observed emission line [OIII]5007, we found a very low oxygen content of about 1/80 of the mean Galactic disk value. This result is consistent with emission line measurements in the ultraviolet wavelength range. The C/O and Ne/O ratios are unusually high and similar to those of another halo object, BoBn-1.

Affiliated with

Also associated with

No associations

Rating

The evolution of planetary nebulae VI. On the chemical composition of the metal-poor PN G135.9+55.9 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The evolution of planetary nebulae VI. On the chemical composition of the metal-poor PN G135.9+55.9, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The evolution of planetary nebulae VI. On the chemical composition of the metal-poor PN G135.9+55.9 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-34031