Variability "Profiles" for T Tauri Variables and Related Objects From AAVSO Visual Observations (Abstract)

Volume 38 number 1 (2010)

John R. Percy

Samantha Esteves

Jou Glasheen

Alfred Lin

Marina Mashintsova

Sophia Wu

Abstract

(Abstract only) T Tauri variables are young sun-like stars in various stages of their birth. The AAVSO has accumulated observations of T Tauri variables and related objects for several decades, but only recently have some of the observations been validated and analyzed (Percy and Palaniappan 2006 JAAVSO 35, 290). Here, we report the analysis of many additional variables, using Fourier and self-correlation analysis. A few variables showed periodic behavior, but self-correlation analysis makes it possible to construct a “variability profile”—amount of variability versus time scale—for all the stars, not just the periodic ones. We will show several examples, and discuss the significance of the results. We will discuss an interesting but spurious low-amplitude one-year periodicity which occurs in a few of the stars, and a possible spurious low-amplitude one-month periodicity. We thank the AAVSO observers who made the measurements, the AAVSO Headquarters staff—especially Elizabeth Waagen—who validated them, and the Natural Sciences and Engineering Research Council of Canada for support.