O'Neal, Douglas

Contact Email: onealdb@wlsc.edu
Institute: West Liberty State College
Research URL:http://www.wlsc.edu/~onealdb
Subject Area: Stellar Atmospheres, Circumstellar Material
Waveband: Optical
Technique: Spectroscopy
Presentation: Poster Display
Title: New results in TiO-band spectroscopy of starspots
Abstract: I present preliminary results from recent observing runs in our ongoing program of studying cool starspots on magnetically active stars via TiO-band spectroscopy. In stars with $T_{\rm eff} > 4200$ K, the TiO bands arise only in the starspots, rather than in the warmer photosphere, and are sensitive indicators of starspot filling factor and temperature. I present echelle spectra (R$\approx$60,000) obtained in March 1998 and May 2000 of four active stars: the RS CVn systems DM UMa and IN Vir; and the active dwarf stars EQ Vir and EK Dra. The spectra contain the TiO bands near 7100 Å and 8860 Å, as well as chromospheric activity indicators including H$\alpha$ and the lines of the Ca II infrared triplet.