Tania A. López–Chico and Luis Salas
Instituto de Astronomía, Universidad Nacional Autónoma de México, Apdo. Postal 877, 22830 Ensenada, B. C., Mexico (tania@astrosen.unam.mx, salas@astrosen.unam.mx)
Received 2006 February 2
Accepted 2006 November 14
RESUMEN
]]> Presentamos un método que utiliza modelos de discos para determinar masas de estrellas T Tauri a partir de fotometría JHK. Encontramos que el exceso infrarrojo producido por el disco se comporta de forma similar a un vector de extinción cuando se grafica en diagramas color–color y color–magnitud, pero son linealmente independientes. Mediante la manupulación de estos vectores como si fueran una base de un espacio vectorial, llevamos a cabo una transformación de coordenadas que nos permite encontrar la masa de la estrella central para una edad dada. Para probar este método basado en vectores principales (PV), comparamos los valores de masa obtenidos (MPV ) en 14 objetos T Tauri de la región de Taurus–Auriga con los valores de masa calculados por métodos dinámicos. También analizamos cuatro sistemas múltiples (GG Tau, FO Tau, FS Tau y V773 Tau) y determinamos la masa de cada componente del sistema. Estudiamos el efecto que se produce al utilizar diferentes modelos evolutivos y la variación de otros parámetros en la determinación de masas por este método.
ABSTRACT
We present a method that uses disk models to determine stellar masses for Pre–Main sequence T Tauri stars from JHK photometry. We find that the infrared excess produced by the disk behaves in a similar way to the extinction vector when plotted on color–color and color–magnitude diagrams, but that it is linearly independent. Employing these vectors as a basis of a vector space we carry out a coordinate transformation that allows us to find the mass of a central star for a given age. To test this Principal Vectors (PV) method we compare the mass values (MPV ) obtained for 14 T Tauri objects in the Taurus–Auriga region with mass values known from dynamical methods. Furthermore, we analyze 4 systems with multiple components (GG Tau, FO Tau, FS Tau, and V773 Tau) and determine the mass for each component of the system. We analyze the effect of using different evolutionary models and other parameter values.
Key Words: STAR: FORMATION — STAR: PRE–MAIN SEQUENCE — TECHNIQUES: PHOTOMETRIC
DESCARGAR ARTÍCULO EN FORMATO PDF
ACKNOWLEDGEMENT
T.A.L.Ch. was partially supported by Conacyt project No.36574–E.
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