Chemical Differentiation around Five Massive Protostars Revealed by ALMA: Carbon-chain Species and Oxygen/Nitrogen-bearing Complex Organic Molecules
Artikel i vetenskaplig tidskrift, 2023
We present Atacama Large Millimeter/submillimeter Array Band 3 data toward five massive young stellar objects (MYSOs), and investigate relationships between unsaturated carbon-chain species and saturated complex organic molecules (COMs). An HC5N (J = 35-34) line has been detected from three MYSOs, where nitrogen (N)-bearing COMs (CH2CHCN and CH3CH2CN) have been detected. The HC5N spatial distributions show compact features and match with a methanol (CH3OH) line with an upper-state energy around 300 K, which should trace hot cores. The hot regions are more extended around the MYSOs where N-bearing COMs and HC5N have been detected compared to two MYSOs without these molecular lines, while there are no clear differences in the bolometric luminosity and temperature. We run chemical simulations of hot-core models with a warm-up stage, and compare with the observational results. The observed abundances of HC5N and COMs show good agreements with the model at the hot-core stage with temperatures above 160 K. These results indicate that carbon-chain chemistry around the MYSOs cannot be reproduced by warm carbon-chain chemistry, and a new type of carbon-chain chemistry occurs in hot regions around MYSOs.
Författare
Kotomi Taniguchi
National Institutes of Natural Sciences
Liton Majumdar
Homi Bhabha National Institute (HBNI)
National Institute of Science Education and Research
Paola Caselli
Max-Planck-Gesellschaft
Shigehisa Takakuwa
Academia Sinica
Kagoshima University
Tien-Hao Hsieh
Max-Planck-Gesellschaft
Masao Saito
National Institutes of Natural Sciences
The Graduate University for Advanced Studies (SOKENDAI)
Zhi-Yun Li
University of Virginia
Kazuhito Dobashi
Tokyo Gakugei University
Tomomi Shimoikura
Otsuma Women's University
Fumitaka Nakamura
University of Tokyo
National Institutes of Natural Sciences
The Graduate University for Advanced Studies (SOKENDAI)
Jonathan Tan
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
University of Virginia
Eric Herbst
University of Virginia
Astrophysical Journal, Supplement Series
0067-0049 (ISSN) 1538-4365 (eISSN)
Vol. 267 1 4Ämneskategorier (SSIF 2011)
Astronomi, astrofysik och kosmologi
Atom- och molekylfysik och optik
Geokemi
DOI
10.3847/1538-4365/acd110