Disk and Envelope Structure in Class 0 Protostars: II. High Resolution Millimeter Mapping of the Serpens Sample

TL;DR

This study uses high-resolution millimeter imaging to detect and analyze the disk and envelope structures of Class 0 protostars in Serpens, revealing early disk formation and providing estimates of disk masses.

Contribution

It presents high-resolution CARMA observations of nine Class 0 protostars, demonstrating early disk formation and estimating disk masses in the Serpens region.

Findings

Evidence for compact disks in all observed protostars

Disk masses range from 0.04 to 1.7 solar masses

Limited multiplicity detected on scales <2000 AU

Abstract

We present high-resolution CARMA 230 GHz continuum imaging of nine deeply embedded protostars in the Serpens Molecular Cloud, including six of the nine known Class 0 protostars in Serpens. This work is part of a program to characterize disk and envelope properties for a complete sample of Class 0 protostars in nearby low-mass star forming regions. Here we present CARMA maps and visibility amplitudes as a function of uv-distance for the Serpens sample. Observations are made in the B, C, D, and E antenna configurations, with B configuration observations utilizing the CARMA Paired Antenna Calibration System. Combining data from multiple configurations provides excellent uv-coverage (4-500 klam), allowing us to trace spatial scales from 1e2 to 1e4 AU. We find evidence for compact disk components in all of the observed Class 0 protostars, suggesting that disks form at very early times (t<0.2 Myr) in Serpens. We make a first estimate of disk masses using the flux at 50 klam, where the contribution from the envelope should be negligible, assuming an unresolved disk. The resulting disk masses range from 0.04 Msun to 1.7 Msun, with a mean of approximately 0.2 Msun. Our high resolution maps are also sensitive to binary or multiple sources with separations > 250 AU, but significant evidence of multiplicity on scales <2000 AU is seen in only one source.