A window on the efficiency of the s-process in AGB stars: chemical abundances of n-capture elements in the planetary nebula NGC 3918

Madonna, S.; García-Rojas, J.; Luridiana, V.; Sterling, N. C.; Morisset, C.
Bibliographical reference

Memorie della Societa Astronomica Italiana, v.87, p.299 (2016)

Advertised on:
2016
Number of authors
5
IAC number of authors
3
Citations
0
Refereed citations
0
Description
The chemical content of the planetary nebula NGC 3918 is investigated through deep, high-resolution (R˜40,000) UVES at VLT spectrophotometric data. We identify and measure more than 750 emission lines, making ours one of the deepest spectra ever taken for a planetary nebula. Among these lines we detect very faint lines of several neutron-capture elements (Se, Kr, Rb, and Xe), which enable us to compute their chemical abundances with unprecedented accuracy, thus constraining the efficiency of the ph s-process and convective dredge-up in the progenitor star of NGC 3918.