Characterizing young protostellar disks with the CALYPSO IRAM-PdBI survey: large Class 0 disks are rare
Maury A. J.; André Ph.; Testi L.; Maret S.; Belloche A.; Hennebelle P.; Cabrit S.; Codella C.; Gueth F.; Podio L.; Anderl S.; Bacmann A.; Bontemps S.; Gaudel M.; Ladjelate B.; Lefèvre C.; Tabone B.; Lefloch B.
Published in A&A, JANUARY 2019Our CALYPSO Large Observing program provided us with deep and high-resolution images of the dust thermal emission in a large sample of the youngest protostars in the Galaxy. The angular resolution and sensitivity allow to probe distances less than 50 AU of the central star (1UA = the average Earth-Sun distance, about 150 million kilometers), a distance corresponding to the size of the most central part of the Solar System, similar to the distance from Pluto to the Sun. We analyzed the spatial distribution of the dust emission to look for disk structures. We reached the surprising conclusion that, while disk formation is concomitant with the formation phase of the protostar, it occurs predominantly (>75%) at much smaller scales than those predicted by hydrodynamic models of the collapse of protostellar cores, and that the effect of magnetic fields could be a key element in explaining these smaller disks.
