A census of dense cores in the Taurus L1495 cloud from the Herschel Gould Belt Survey
Résumé
We present a catalogue of dense cores in a similar to 4 degrees x 2 degrees field of the Taurus star-forming region, inclusive of the L1495 cloud, derived from Herschel SPIRE and PACS observations in the 70 mu m, 160 mu m, 250 mu m, 350 mu m, and 500 mu m continuum bands. Estimates of mean dust temperature and total mass are derived using modified blackbody fits to the spectral energy distributions. We detect 525 starless cores of which similar to 10-20 per cent are gravitationally bound and therefore presumably prestellar. Our census of unbound objects is similar to 85 per cent complete for M \textgreater 0.015 M-circle dot in low-density regions (A(V) less than or similar to 5 mag), while the bound (prestellar) subset is similar to 85 per cent complete for M \textgreater 0.1 M-circle dot overall. The prestellar core mass function (CMF) is consistent with lognormal form, resembling the stellar system initial mass function, as has been reported previously. All of the inferred prestellar cores lie on filamentary structures whose column densities exceed the expected threshold for filamentary collapse, in agreement with previous reports. Unlike the prestellar CMF, the unbound starless CMF is not lognormal, but instead is consistent with a power-law form below 0.3 M-circle dot and shows no evidence for a low-mass turnover. It resembles previously reported mass distributions for CO clumps at low masses (M less than or similar to 0.3 M-circle dot). The volume density PDF, however, is accurately lognormal except at high densities. It is consistent with the effects of self-gravity on magnetized supersonic turbulence. The only significant deviation from lognormality is a high-density tail which can be attributed unambiguously to prestellar cores.
| Origine | Fichiers éditeurs autorisés sur une archive ouverte |
|---|
