Resumen
It is known that in the formation of a star, accretion of mass through a circumstellar disk is accompanied by the ejection of a fraction of this material through jets and outflows. It is usually assumed that this fraction is fixed in time, or that it slowly evolves on the star formation timescale of 105 to 106 yr. But, is this true? Do accretion and ejection follow each other within samples of objects, or in time for a given object? We present preliminary results of a project aimed at testing the relation between accretion and ejection of mass in star formation. The first component of the project looks for radio-jet ejections in young stellar objects (YSOs) known to have accretion-related infrared outbursts. The second component is a radio/IR time monitoring with facilities such as the JVLA and the VLT of a large number of YSOs in some of the nearest star forming clouds.
