The JCMT Gould Belt Survey: SCUBA-2 observations of circumstellar discs in L 1495

Abstract

We present 850 µm and 450 µm data from the JCMT Gould Belt Survey obtained with SCUBA-2 and characterise the dust attributes of Class I, Class II and Class III disk sources in L 1495. We detect 23% of the sample at both wavelengths, with the detection rate decreasing through the Classes from I-III. The median disk mask is 1.6 ×10 −3 M , and only 7% of Class II sources have disk masses larger than 20 Jupiter masses. We detect a higher proportion of disks towards sources with stellar hosts of spectral type K than spectral type M. Class II disks with single stellar hosts of spectral type K have higher masses than those of spectral type M, supporting the hypothesis that higher mass stars have more massive disks. Variations in disk masses calculated at the two wavelengths suggests there may be differences in dust opacity and/or dust temperature between disks with hosts of spectral types K to those with spectral type M.

Submillimetre Studies of Prestellar and Starless Cores in the Ophiuchus, Taurus and Cepheus Molecular Clouds

“…Palmeirim et al (2013) proposed that material is accreting onto the L1495 filament along 'striations' -thin streams of emission running perpendicular to the filament's length. Palmeirim et al (2013) further noted that these striations lie parallel to the local magnetic field vectors -as determined by Goldsmith et al The data were reduced as described in Section 2.1.2, using the Internal Release 1 method (Buckle et al 2015). Continuum observations at 450 and 850 µm were made using fully sampled 15-, 30-, and 60-arcmin diameter circular regions (PONG900, 1800 and 3600 mapping modes - Bintley et al 2014).…”

“…Taurus is a quiescent region with well-defined filaments, in which star formation appears to be occurring in a dispersed mode (Kenyon et al 2008). A particularly prominent filament is the L1495/B213/B211 filament in the northwest of Taurus, the head of which was observed as part of the JCMT GBS (Buckle et al 2015). This extremely well-defined filament has been the subject of many studies, attempting to explain its formation and to determine its evolutionary state (e.g.…”

“…The final output map is centred at a position of R.A. (2000) = 04 h 17 m 54 s , Dec. (2000) = +28 • 05 ′ 24 ′′ . These data were first presented by Buckle et al (2015), who provide full details of the observations. We only use the 850-µm data here.…”

“…We measured the 1 − σ RMS noise on the low-variance regions of the SCUBA-2 850-µm map to be 0.9 ± 0.2 mJy/6-arcsec pixel and on the unfiltered 250-µm map Buckle et al 2015). Cores are numbered as in Table 4.1.…”

“…Data and models used in this thesis that are not my own are clearly cited in the text. 4.2 The centre of the L1495 region, as observed at the five Herschel wavelengths, 70, 160, 250, 350 and 500µm (Marsh et al 2014;Marsh et al 2015) and SCUBA-2 850 µm (Buckle et al 2015). .12 Plot of core mass against deconvolved size.…”