We present deep, high-resolution (R~40000) UVES at VLT spectrophotometric data of the planetary nebula NGC 3918. This is one of the deepest spectra ever taken of a planetary nebula. We have identified and measured more than 700 emission lines and, in particular, we have detected very faint lines of several neutron-capture elements (s-process elements: Kr, Xe and Rb) that enable us to compute their chemical abundances with unprecedented accuracy, thus constraining the efficiency of the s-process and convective dredge-up.
@article{arxiv.1412.2071,
title = {s-process Enrichment in the Planetary Nebula NGC 3918},
author = {J. García-Rojas and S. Madonna and V. Luridiana and N. C. Sterling and C. Morisset},
journal= {arXiv preprint arXiv:1412.2071},
year = {2014}
}
Comments
to appear in "Highlights of Spanish Astrophysics VIII" Proceedings of the VIII Spanish Astronomical Society meeting. Eds. A. J. Cenarro, F. Figueras, C. Hern\'andez-Monteagudo, J. Trujillo, L. Valdivielso. 1 table and 3 figures