Protostars and Planets VI, Heidelberg, July 15-20, 2013
Evolution of disks in the Lambda Ori Star Formin Region
Bayo, Amelia (ESO / MPIA)
Barrado, David (CAB, INTA-CSIC, Madrid)
Huelamo, Nuria (CAB, INTA-CSIC, Madrid)
Morales-Calderon, Maria (CAB, INTA-CSIC, Madrid)
Melo, Claudio (ESO)
Stauffer, John (SSC, Caltech)
Stelzer, Beate (INAF)
Most observational studies so far point towards brown dwarfs (BDs) having a similar formation mechanism as the one accepted for low mass stars. In this context, one would expect the disks around the lowest mass end of the IMF to behave in a similar manner as those around slightly higher mass stars. However, observational evidence on properties such as disk life times, put some caveats to this idea.
To further understand this issue, and with a very complete spectroscopic census of Collinder 69 (C69, the central cluster of the LOSFR) as the starting point; we have studied accretion, activity and rotation of the members of this cluster. We present analogies and difference between the stellar and brown dwarf populations as well as comparisons with other star forming regions of similar and different ages to address environmental effects:
1.- We estimate a BD accretion fraction in C69 between 30 and 43%, similar to that of low-mass stars in the same region and compatible with that of BDs reported in the literature for other regions such as Upper Sco (31% acc to Scholz et al. 2007)
2.- We report two changes in the cumulative disk fraction function at 0.3 and 0.6Msun that could trace differences in the disk dissipation mechanism or the disk locking to the central star.
Click here to view poster PDF