Bibcode
Barentsen, Geert; Vink, Jorick S.; Drew, J. E.; Greimel, R.; Wright, N. J.; Drake, J. J.; Martin, E. L.; Valdivielso, L.; Corradi, R. L. M.
Referencia bibliográfica
Monthly Notices of the Royal Astronomical Society, Volume 415, Issue 1, pp. 103-132.
Fecha de publicación:
7
2011
Número de citas
93
Número de citas referidas
86
Descripción
The Isaac Newton Telescope (INT) Photometric H-Alpha Survey (IPHAS) is a
1800 deg2 survey of the Northern Galactic Plane, reaching
down to r'˜ 21. We demonstrate how the survey can be used to (1)
reliably select classical T Tauri star candidates and (2) constrain the
mass accretion rates with an estimated relative uncertainty of 0.6 dex.
IPHAS is a necessary addition to spectroscopic surveys because it allows
large and uniform samples of accretion rates to be obtained with a
precise handle on the selection effects.
We apply the method on a region of 7 deg2 towards the H II
region IC 1396 in Cepheus OB2 and identify 158 pre-main-sequence
candidates with masses between 0.2 and 2.0 M&sun; and
accretion rates between 10-9.2 and 10-7.0
M&sun; yr-1. We find a power-law dependency
between the stellar mass and the accretion rates with a slope of
α= 1.1 ± 0.2, which is less steep than indicated by
previous studies. We discuss the influence of method-dependent
systematic effects on the determination of this relationship.
The majority of our sample consists of faint, previously unknown,
low-mass T Tauri candidates (56 per cent between 0.2 and 0.5
M&sun;). Many candidates are clustered in front of three
bright-rimmed molecular clouds, which are being ionized by the massive
star HD 206267 (O6.5V). We discover a spatio-temporal gradient of
increasing accretion rates, increasing Spitzer infrared excess, and
younger ages away from the ionizing star, providing a strong indication
that the formation of these clusters has been sequentially triggered by
HD 206267 during the last ˜1 Myr.
Proyectos relacionados
![Imagen con el Telescopio Espacial (HST) de la Nebulosa Planetaria "Necklace" ("el collar de perlas") descubierta por nuestro grupo en 2005 usando el Telescopio Isaac Newton (INT) en el Observatorio del Roque de los Muchachos (proyecto IPHAS de cartografiado en H-alfa del Plano Galáctico). Esta Planetaria se ha convertido en una pieza clave para entender la formación de nebulosas bipolares en sistemas con estrellas progenitoras binarias (Corradi+2011). Nebulosa Planetaria "Necklace"](/sites/default/files/styles/crop_square_2_2_to_320px/public/images/project/Imagen%20AMR.jpg?itok=S55dQ216)
Nebulosas Bipolares
Nuestro proyecto persigue tres objetivos principales: 1) Determinar las condiciones físico-químicas de las nebulosas planetarias con geometría bipolar y de las nebulosas alrededor de estrellas simbióticas. El fin es entender el origen de la bipolaridad y poner a prueba los modelos teóricos que intentan explicar la morfología y la cinemática nebular
Antonio
Mampaso Recio