Dredge for Chara

Chara Technical Report

In response to the accumulation of the first substantial collection of observational data from the CHARA Array, obtained during the fall of 2001, a series of Mathcad programs has been developed as a means for reducing these data to calibrated visibilities. The Mathcad tools developed to date include routines that calculate estimated visibilities for single and double stars, ephemeredes from bin...

A Matrix Chara terization for MELL

Manifest Chara terization and Testing for Certain

Third-dredge-up Oxygen in Planetary Nebulae?

The planetary nebulae He 2-436 and Wray 16-423 in the Sagittarius dwarf galaxy appear to result from nearly twin stars, except that third-dredge-up carbon is more abundant in He 2-436. A thorough photoionization-model analysis implies that ratios Ne/O, S/O and Ar/O are significantly smaller in He 2436, indicative of third-dredge-up oxygen enrichment. The enrichment of oxygen with respect to car...

Agb Evolution with Overshoot: Hot Bottom Burning and Dredge Up

We calculated models of massive AGB stars with a self-consistent coupling of timedependent mixing and nuclear burning for 30 isotopes and 74 reactions. Overshoot with an exponentially declining velocity field was considered and applied during all stages of evolution and in all convective regions. Very efficient 3 dredge-up was found even overcompensating the growth of the hydrogenexhausted core...