We present Herschel observations from the Herschel Gould Belt Survey and SCUBA-2 science verification observations from the JCMT Gould Belt Survey of the B1 clump in the Perseus molecular cloud .
We determined the dust emissivity index using four different techniques to combine the Herschel PACS+SPIRE data at 160 - 500 \mu m with the SCUBA-2 data at 450 \mu m and 850 \mu m. Of our four techniques , we found the most robust method was to filter-out the large-scale emission in the Herschel bands to match the spatial scales recovered by the SCUBA-2 reduction pipeline .
Using this method , we find \beta \approx 2 towards the filament region and moderately dense material and lower \beta values ( \beta \gtrsim 1.6 ) towards the dense protostellar cores , possibly due to dust grain growth .
We find that \beta and temperature are more robust with the inclusion of the SCUBA-2 data , improving estimates from Herschel data alone by factors of \sim 2 for \beta and by \sim 40 % Â for temperature .
Furthermore , we find core mass differences of \lesssim 30 % Â compared to Herschel -only estimates with an adopted \beta = 2 , highlighting the necessity of long wavelength submillimeter data for deriving accurate masses of prestellar and protostellar cores .