Open Access

Fig. 15


Flux ratio of HNC to HCN plotted against PN central star UV luminosity. Line ratios obtained from observations by Schmidt & Ziurys (2017a) are denoted by crosses. CSPN UV luminosities from Table 1 and Bachiller et al. (1989b, NGC 2346), Frew (2008, NGC 2440 and Hb 5), and Sabbadin et al. (1984, M 1-7). The best-fit linear power-law slope (black dashed line, NGC 7027 and literature sources omitted) is m = − 0.363 with a linear correlation coefficient of r = − 0.885. Typical uncertainty estimate of 40% for UV luminosity and 10% for line ratios is plotted in the top right.

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.