Soyoung Youn, Sungeun Kim
We present a 1.1 mm emission map of the OMC1 region observed with AzTEC, a new large-format array composed of 144 silicon-nitride micromesh bolometers that was in use at the James Clerk Maxwell Telescope (JCMT). The AzTEC observations of the OMC1 region at 1.1 mm reveal dozens of cloud cores and a tail of filaments in a manner that is almost identical to the submillimeter continuum emission of the entire OMC1 region at 450 and 850 micronm. We perform Fourier analysis of the image with a modified periodogram and the density power spectrum which provides the distribution of length scale of the structures is measured. The expected value of the periodogram converges to the resulting power spectrum in the mean squared sense. From the present analysis of the OMC1 filaments at the 1.1 mm emission, the power spectrum steepens at relatively smaller scales. At largest scales, the power spectrum flattens and the large scale power law becomes shallower. The power spectra of the 1.1 mm emission show clear deviations from a single power law. We find that at least three components of power law might be fitted to the calculated power spectrum of the 1.1 mm emission. The slope of the best fit power law, $\gamma \approx -2.7$ is similar to those values in numerical simulations. The effects of beam size and the noise spectrum on the shape and slope of the power spectrum are also included in the present analysis. The slope of the power law changes significantly at higher spatial frequency as the beam size increases.
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http://arxiv.org/abs/1206.0826
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