Complex Organic Molecules tracing shocks along the outflow cavity in the high-mass protostar IRAS20126+4104

Abstract

We report on subarcsecond observations of complex organic molecules (COMs) in the high-mass protostar IRAS20126+4104 with the Plateau de Bure Interferometer in its most extended configurations. In addition to the simple molecules SO, HNCO and H2-13CO, we detect emission from CH3CN, CH3OH, HCOOH, HCOOCH3, CH3OCH3, CH3CH2CN, CH3COCH3, NH2CN, and (CH2OH)2. SO and HNCO present a X-shaped morphology consistent with tracing the outflow cavity walls. Most of the COMs have their peak emission at the putative position of the protostar, but also show an extension towards the south(east), coinciding with an H2 knot from the jet at about 800-1000 au from the protostar. This is especially clear in the case of H2-13CO and CH3OCH3. We fitted the spectra at representative positions for the disc and the outflow, and found that the abundances of most COMs are comparable at both positions, suggesting that COMs are enhanced in shocks as a result of the passage of the outflow. By coupling a parametric shock model to a large gas-grain chemical network including COMs, we find that the observed COMs should survive in the gas phase for about 2000 yr, comparable to the shock lifetime estimated from the water masers at the outflow position. Overall, our data indicate that COMs in IRAS20126+4104 may arise not only from the disc, but also from dense and hot regions associated with the outflow.

accepted in MNRAS. Figures of Appendix A upon request to first author

Cited by in corpus (16)

• Formation and Evolution of Disks around Young Stellar Objects
• Implications of a hot atmosphere/corino from ALMA observations towards NGC1333 IRAS 4A1
• ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -- VIII. A search for hot cores by using C${}_2$H${}_5$CN, CH${}_3$OCHO and CH${}_3$OH lines
• An Asymmetric Keplerian Disk Surrounding the O-type Protostar IRAS16547$-$4247
• Widespread Presence of Glycolaldehyde and Ethylene Glycol Around Sagittarius B2
• Chemistry of the High-Mass Protostellar Molecular Clump IRAS 16562-3959
• Rotational Desorption of Ice Mantles and Complex Molecules from Suprathermally Rotating Dust Grains around Young Stellar Objects
• Chemical evolution of the gas in C-type shocks in dark clouds
• Chemical models of adenine precursors cyanamide and carbodiimide in the interstellar medium
• Probing the kinematics and chemistry of the hot core Mon R 2 IRS 3 using ALMA observations
• High Resolution Observations of the Massive Protostar in IRAS18566+0408
• Multi-wavelength modelling of the circumstellar environment of the massive proto-star AFGL 2591 VLA 3
• Interstellar Complex Organic Molecules in SiO-traced massive outflows
• Modelling cosmic masers in C-type shock waves -- the coexistence of Class I CH3OH and 1720 MHz OH masers
• Different molecular filament widths as tracers of accretion onto filaments
• SMA line observations of the CH${}_3$OH-maser outflow in DR21(OH)