Soft X-ray emissions of Si IX in Procyon
| dc.creator | Liang, Guiyun | |
| dc.creator | Zhao, Gang | |
| dc.date | 2006-08-07 | |
| dc.date.accessioned | 2026-07-07T10:23:24Z | |
| dc.date.available | 2026-07-07T10:23:24Z | |
| dc.description | An analysis of $n=3 \to 2$ transition lines of carbon-like silicon reveals that some ratios of line intensities are sensitive to the electron density. The ratio between two group of $3d\to2p$ transition lines at 55.246 Åand 55.346 Åis a good $n_{\rm e}$-diagnostic technique, due to its insensitivity to the electron temperature. Using this property, a lower limit of the density of 0.6$\times10^8$cm$^{-3}$ is derived for Procyon, which is consistent with that constrained by C V and Si X emissions. Significant discrepancies in ratios of $3s\to2p$ lines to $3d\to2p$ lines between theoretical predictions and observed values, are found, by the spectral analysis of Procyon observed with the {\it Chandra} High Resolution Transmission Grating spectra. The difference exceeding a factor of 3, cannot be explained by the uncertainty of atomic data. The opacity effect is also not a choice as reported by Ness and co-workers. For the $3s\to2p$ line at 61.611 Å, present work indicates that the large discrepancy may be due to the contamination from a S VIII line at 61.645 Å. For the lines at 61.702 and 61.846 Å, we suggest that the discrepancies may be attributed to contaminations of unknown lines. | |
| dc.description | 18 pages, 4 figures, accepted by New Astronomy | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0608144 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0608144 | |
| dc.identifier | NewAstron.12:435-440,2007 | |
| dc.identifier | doi:10.1016/j.newast.2007.01.001 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/175815 | |
| dc.subject | Astrophysics | |
| dc.title | Soft X-ray emissions of Si IX in Procyon | |
| dc.type | text |