Spectral Indications of Density Variability in the Corona of Ad Leonis
نویسنده
چکیده
Direct comparison of high-resolution X-ray spectra of the active dMe star AD Leo, observed three times with Chandra, shows variability of key density-sensitive lines, possibly due to flaring activity. In particular, a significant long-duration enhancement of the coronal density is indicated by the Ne IX and Si XIII He-like triplets, and possibly also by density-sensitive Fe XXI line ratios. Subject headings: stars: individual (AD Leo) — stars: activity — stars: coronae — stars: late-type — X-rays: stars
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