Organic Complexity In Protostellar Disk Candidates

We present ALMA observations of organic molecules towards five low-mass Class 0/I protostellar disk candidates in the Serpens cluster.

Three sources (Ser-emb 1, Ser-emb 8, and Ser-emb 17) present emission of CH3OH as well as CH3OCH3, CH3OCHO, and CH2CO, while NH2CHO is detected in just Ser-emb 8 and Ser-emb 17. Detecting hot corino-type chemistry in three of five sources represents a high occurrence rate given the relative sparsity of these sources in the literature, and this suggests a possible link between protostellar disk formation and hot corino formation. For sources with CH3OH detections, we derive column densities of 10^{17}-10^{18} cm^{-2} and rotational temperatures of ~200-250 K. The CH3OH-normalized column density ratios of large, oxygen-bearing COMs in the Serpens sources and other hot corinos span two orders of magnitude, demonstrating a high degree of chemical diversity at the hot corino stage. Resolved observations of a larger sample of objects are needed to understand the origins of chemical diversity in hot corinos, and the relationship between different protostellar structural elements on disk-forming scales.

Jennifer B. Bergner, Rafael Martin-Domenech, Karin I. Oberg, Jes K. Jorgensen, Elizabeth Artur de la Villarmois, Christian Brinch
(Submitted on 17 Jul 2019)

Comments: Accepted to ACS Earth & Space Chemistry
Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA)
DOI: 10.1021/acsearthspacechem.9b00059
Cite as: arXiv:1907.07791 [astro-ph.SR] (or arXiv:1907.07791v1 [astro-ph.SR] for this version)
Submission history
From: Jennifer Bergner
[v1] Wed, 17 Jul 2019 22:05:16 UTC (5,734 KB)
https://arxiv.org/abs/1907.07791
Astrobiology, Astrochemistry