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The Spitzer Space Telescope mapped the Perseus molecular cloud complex with IRAC and MIPS as part of the c2d Spitzer Legacy project. This paper combines the observations from both instruments giving an overview of low-mass star formation across Perseus from 3.6 to 70 micron. We provide an updated list of young stellar objects with new classifications and source fluxes from previous works, identifying 369 YSOs in Perseus with the Spitzer dataset. By synthesizing the IRAC and MIPS maps of Perseus and building on the work of previous papers in this series (Jorgensen et al. 2006, Rebull et al. 2007), we present a current census of star formation across the cloud and within smaller regions. 67% of the YSOs are associated with the young clusters NGC 1333 and IC 348. The majority of the star formation activity in Perseus occurs in the regions around the clusters, to the eastern and western ends of the cloud complex. The middle of the cloud is nearly empty of YSOs despite containing regions of high visual extinction. The western half of Perseus contains three-quarters of the total number of embedded YSOs (Class 0+I and Flat SED sources) in the cloud and nearly as many embedded YSOs as Class II and III sources. Class II and III greatly outnumber Class 0+I objects in eastern Perseus and IC 348. These results are consistent with previous age estimates for the clusters. Across the cloud, 56% of YSOs and 91% of the Class 0+I and Flat sources are in areas where Av > 5 mag, indicating a possible extinction threshold for star formation.
We have mapped 63 regions forming high-mass stars in CS J=5-4 using the CSO. The CS peak position was observed in C34S J=5-4 towards 57 cores and in 13CS J=5-4 towards the 9 brightest cores. The sample is a subset of a sample originally selected toward water masers; the selection on maser sources should favor sources in an early stage of evolution. The integrated intensity of CS J=5-4 correlates very well with the dust continuum emission at 350 microns. The distributions of size, virial mass, surface density, and luminosity are all peaked with a few cores skewed towards much larger values than the mean. We find a weak correlation between C34S linewidth and size, consistent with Dv ~ R^{0.3}. The linewidths are much higher than would be predicted by the usual relations between linewidth and size determined from regions of lower mass. These regions are very turbulent. The derived virial mass agrees within a factor of 2 to 3 with mass estimates from dust emission at 350 microns after corrections for the density structure are accounted for. The resulting cumulative mass spectrum of cores above 1000 solar masses can be approximated by a power law with a slope of about -0.9, steeper than that of clouds measured with tracers of lower density gas and close to that for the total masses of stars in OB associations. The median turbulent pressures are comparable to those in UCHII regions, and the pressures at small radii are similar to those in hypercompact-HII regions (P/k ~ 10^{10} K cm^{-3}). The filling factors for dense gas are substantial, and the median abundance of CS is about 10^{-9}. The ratio of bolometric luminosity to virial mass is much higher than the value found for molecular clouds as a whole, and the correlation of luminosity with mass is tighter. (Abridged).
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