Letter to the Editor

Cerium: The lithium substitute in post-AGB stars^*

¹ Departement Natuurkunde en Sterrenkunde, K.U. Leuven, Celestijnenlaan 200B, 3000 Leuven, Belgium
² Astrophysique et Spectroscopie, Université de Mons-Hainaut, 7000 Mons, Belgium
³ Institut de Physique Nucléaire, Atomique et de Spectroscopie (IPNAS), Université de Liège, 4000 Liège, Belgium

Corresponding author: M. Reyniers, maarten.reyniers@ster.kuleuven.ac.be

Received: 2 August 2002
Accepted: 14 October 2002

Abstract

In this letter we present an alternative identification for the line detected in the spectra of s-process enriched low-mass post-AGB stars around 6708 Å  and which was interpreted in the literature as due to Li. Newly released line lists of lanthanide species reveal, however, the likely identification of the line to be due to a Ce ii transition. We argue that this identification is consistent with the Ce abundance of all the objects discussed in the literature and conclude that in none of the low-mass s-process enriched post-AGB stars there is indication for Li-production.