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The low-mass young stellar population in Orion OB1

Cesar Briceño·Nuria Calvet·Anna K. Vivas·L. Hartmann·.
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Abstract

We present recent results from our ongoing large scale variability survey of the Orion OB1 Association. In an area of ~ 25 square degrees we have unveiled new populations of low-mass young stars over a range of environments, and ages from 1-2 Myr in Ori OB 1b to roughly 10 Myr in Ori OB 1a. There is a lack of strong Ha emission and near-IR excesses in the young stars of Ori OB 1a, suggesting that accretion stops and disks dissipate for most solar type stars in a few Myr, probably caused by of the onset of planet formation. The absence of dust and gas in Ori OB 1a is consistent with the picture of star formation as a rapid process, in which molecular clouds dissipate in just a few Myr after the first stars are born.

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Cesar Briceño, Nuria Calvet, Anna K. Vivas, L. Hartmann, .. 2002-02-19. The low-mass young stellar population in Orion OB1. https://arxiv.org/abs/astro-ph/0202350

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