Letter to the Editor

The Ne/O abundance ratio in the quiet Sun

CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX, UK e-mail: p.r.young@rl.ac.uk

Received: 6 October 2005
Accepted: 26 October 2005

Abstract

Context.

Aims.To determine the neon-to-oxygen abundance in the quiet Sun, a proxy for the photospheric abundance ratio.

Methods.An emission measure method applied to extreme ultraviolet emission lines of Ne iv–vi and O iii–v ions observed by the Coronal Diagnostic Spectrometer on the SOHO satellite.

Results.The average Ne/O abundance ratio in supergranule cell centre regions is , while in supergranule network regions is . A photospheric Ne/O ratio of is suggested, in good agreement with the most recent compilation of solar photospheric abundances, but discrepant with a recent Ne/O ratio derived from stellar X-ray spectra and revised neon abundances suggested from solar interior models.

Conclusions.