A Comprehensive Study of the L1551 IRS 5 Binary System

We model the Class I source L1551 IRS 5, adopting a flattened infallingenvelope surrounding a binary disk system and a circumbinary disk. With ourcomposite model, we calculate self-consistently the spectral energydistribution of each component of the L1551 IRS 5 system, using additionalconstraints from recent observations by ISO, the water ice feature fromobservations with SpeX, the SCUBA extended spatial brightness distribution atsub-mm wavelengths, and the VLA spatial intensity distributions at 7 mm of thebinary disks. We analyze the sensitivity of our results to the variousparameters involved. Our results show that a flattened envelope collapse modelis required to explain simultaneously the large scale fluxes and the water iceand silicate features. On the other hand, we find that the circumstellar disksare optically thick in the millimeter range and are inclined so that theirouter parts hide the emission along the line of sight from their inner parts.We also find that these disks have lower mass accretion rates than the infallrate of the envelope.Comment: 38 pages, 13 figures. To appear in ApJ (v586 April 1, 2003 issue