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 after 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 of five young stellar objects (YSOs) that have undergone outbursts within the past 100 yr and catalog the volatile chemistry found within ∼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 expected for a spectra signature for a postoutburst 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.