NUK - logo
E-viri
Recenzirano Odprti dostop
  • A census of dense cores in ...
    Marsh, K. A; Kirk, J. M; André, Ph; Griffin, M. J; Könyves, V; Palmeirim, P; Men'shchikov, A; Ward-Thompson, D; Benedettini, M; Bresnahan, D. W; Francesco, J. Di; Elia, D; Motte, F; Peretto, N; Pezzuto, S; Roy, A; Sadavoy, S; Schneider, N; Spinoglio, L; White, G. J

    Monthly notices of the Royal Astronomical Society, 06/2016, Letnik: 459, Številka: 1
    Journal Article

    We present a catalogue of dense cores in a ∼4° × 2° field of the Taurus star-forming region, inclusive of the L1495 cloud, derived from Herschel SPIRE and PACS observations in the 70 μm, 160 μm, 250 μm, 350 μm, and 500 μm 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 ∼10–20 per cent are gravitationally bound and therefore presumably prestellar. Our census of unbound objects is ∼85 per cent complete for M > 0.015 M⊙ in low-density regions (A V ≲ 5 mag), while the bound (prestellar) subset is ∼85 per cent complete for M > 0.1 M⊙ 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⊙ and shows no evidence for a low-mass turnover. It resembles previously reported mass distributions for CO clumps at low masses (M ≲ 0.3 M⊙). 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.