The SCUBA HAlf Degree Extragalactic Survey – VI. 350‐μm mapping of submillimetre galaxies

UK ATC, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ
Monthly Notices of the Royal Astronomical Society (Impact Factor: 5.11). 03/2008; 384(4):1597 - 1610. DOI: 10.1111/j.1365-2966.2007.12808.x
Source: OAI


ABSTRACTA follow-up survey using the Submillimetre High-Angular Resolution Camera (SHARC-II) at 350 μm has been carried out to map the regions around several 850-μm-selected sources from the Submillimetre HAlf Degree Extragalactic Survey (SHADES). These observations probe the infrared (IR) luminosities and hence star formation rates in the largest existing, most robust sample of submillimetre galaxies (SMGs). We measure 350-μm flux densities for 24 850-μm sources, seven of which are detected at ≥2.5σ within a 10 arcsec search radius of the 850-μm positions. When results from the literature are included the total number of 350-μm flux density constraints of SHADES SMGs is 31, with 15 detections. We fit a modified blackbody to the far-IR (FIR) photometry of each SMG, and confirm that typical SMGs are dust-rich (Mdust≃ 9 × 108 M⊙), luminous (LFIR≃ 2 × 1012 L⊙) star-forming galaxies with intrinsic dust temperatures of ≃35 K and star formation rates of ≃400 M⊙ yr−1. We have measured the temperature distribution of SMGs and find that the underlying distribution is slightly broader than implied by the error bars, and that most SMGs are at 28 K with a few hotter. We also place new constraints on the 350-μm source counts, N350(>25 mJy) ∼ 200–500 deg−2.

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Available from: Mattia Vaccari
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    • "At 850 µm, the opacity of the atmosphere is sufficiently low to allow observations from the ground. The counts at this wavelength resolve only 20-30% of the CIB [26]. Deeper counts, resolving the bulk of the CIB, are derived in fields lensed by low-z galaxy clusters, where the error budget is dominated by the large scale structure (narrow field) [35] [28]. "
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