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arXiv · 2409.04530

Complex Organics Surrounding the FU Ori-Type Object V1057 Cyg Indicative of Sublimated Ices

Abstract

FU Ori and EX Lup type objects present natural experiments for understanding a critical stage in the star and planet formation process. These objects offer insight into the diversity of molecules available to forming planetary systems due to a sudden increase in accretion and central luminosity causes the disk and surrounding material to increase in temperature. This allows for volatiles to sublimate off of grains and exist in the gas-phase for tens to hundreds of years post initial outburst. While this dynamic stage may be common for solar-type protostars, observations of the chemical impact of these bursts are rare. In this article, we present observations from the NOrthern Extended Millimeter Array (NOEMA) of five Young Stellar Objects (YSOs) that have undergone outbursts within the past 100 years and catalog the volatile chemistry found within approx 1000 au of the YSO. Only one source clearly shows a line rich spectra with >11 molecules detected including complex organics and water, as is an expected spectra signature for a post-outburst source. This source is V1057 Cyg, and we present it as the northern analog to the well studied and molecule-rich FU Ori source, V883 Ori. Our conclusions on the chemical inventory of the other four sources in our sample are sensitivity limited, as V1057 Cyg contains the highest disk/envelope gas mass.

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Jenny K. Calahan, Edwin A. Bergin, Merel van't Hoff, Alice Booth, Karin Öberg, Ke Zhang, Nuria Calvet, Lee Hartmann. 2024-09-06. Complex Organics Surrounding the FU Ori-Type Object V1057 Cyg Indicative of Sublimated Ices. https://arxiv.org/abs/2409.04530

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