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Abstract The ALMA survey of Gas Evolution in PROtoplanetary disks (AGE-PRO) Large Program aims to trace the evolution of gas disk mass and size throughout the lifetime of protoplanetary disks by using the Atacama Large Millimeter/submillimeter Array (ALMA). This paper presents Band-6 ALMA observations of 10 embedded (Class I and Flat Spectrum) sources in the Ophiuchus molecular cloud, with spectral types ranging from M3 to K6 stars, which serve as the evolutionary starting point in the AGE-PRO sample. While we find four nearly edge-on disks (≥70°), and three highly inclined disks (≥60°) in our sample, we show that, as a population, embedded disks in Ophiuchus are not significantly contaminated by more-evolved, but highly inclined sources. We derived dust disk masses from the Band-6 continuum and estimated gas disk masses from the C18OJ= 2−1 and C17OJ= 2−1 lines. The mass estimates from the C17O line are slightly higher, suggesting C18O emission might be partially optically thick. While the12CO and13CO lines are severely contaminated by extended emission and self-absorption, the C18O and C17O lines are allowed to trace the radial extent of the gaseous disks. From these measurements, we found that the C18OJ= 2−1 and C17OJ= 2−1 fluxes correlate well with each other and with the continuum fluxes. Furthermore, the C18O and C17O lines present a larger radial extension than disk dust sizes by factors ranging from ∼1.5 to ∼2.5, as is found for Class II disks using the radial extension of the12CO. In addition, we have detected outflows in three disks from12CO observations.
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Data from "High Resolution ALMA Observations of Richly Structured Protoplanetary Disks in sigma Orionis"
Data associated with Huang et al., "High Resolution ALMA Observations of Richly Structured Protoplanetary Disks in σ Orionis," accepted by ApJ. The raw data can be obtained from the ALMA archive under program IDs 2016.1.00447.S (PI: J. Williams) and 2022.1.00728.S (PI: J. Huang). Contents images.tar: FITS files of the ALMA continuum images of the eight disks reductionscripts.tar: CASA reduction scripts visibilities.tar: Continuum measurement sets for the eight disks (note that the weights in these measurement sets are not rescaled)
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- Award ID(s):
- 2307916
- PAR ID:
- 10556451
- Publisher / Repository:
- Zenodo
- Date Published:
- Format(s):
- Medium: X
- Right(s):
- Creative Commons Attribution 4.0 International; Creative Commons Attribution 4.0 International
- Sponsoring Org:
- National Science Foundation
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