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تسجيل مستخدم جديدThe JCMT Gould Belt Survey: Evidence for Dust Grain Evolution in Perseus Star-forming Clumps
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The dust emissivity spectral index, $beta$, is a critical parameter for deriving the mass and temperature of star-forming structures, and consequently their gravitational stability. The $beta$ value is dependent on various dust grain properties, such as size, porosity, and surface composition, and is expected to vary as dust grains evolve. Here we present $beta$, dust temperature, and optical depth maps of the star-forming clumps in the Perseus Molecular Cloud determined from fitting SEDs to combined Herschel and JCMT observations in the 160 $mu$m, 250 $mu$m, 350 $mu$m, 500 $mu$m, and 850 $mu$m bands. Most of the derived $beta$, and dust temperature values fall within the ranges of 1.0 - 2.7 and 8 - 20 K, respectively. In Perseus, we find the $beta$ distribution differs significantly from clump to clump, indicative of grain growth. Furthermore, we also see significant, localized $beta$ variations within individual clumps and find low $beta$ regions correlate with local temperature peaks, hinting at the possible origins of low $beta$ grains. Throughout Perseus, we also see indications of heating from B stars and embedded protostars, as well evidence of outflows shaping the local landscape.
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