English

Study of Complex Nitrogen and Oxygen-bearing Molecules toward the High-mass Protostar IRAS 18089$-$1732

Astrophysics of Galaxies 2024-05-15 v2 Chemical Physics

Abstract

The observation of oxygen (O)- and nitrogen (N)-bearing molecules gives an idea about the complex prebiotic chemistry in the interstellar medium (ISM). In this article, we present the identification of the rotational emission lines of N-bearing molecules ethyl cyanide (C2_{2}H5_{5}CN), cyanoacetylene (HC3_{3}N), and O-bearing molecules methyl formate (CH3_{3}OCHO) towards high-mass protostar IRAS 18089-1732 using the Atacama Compact Array (ACA). We also detected the emission lines of both N- and O-bearing molecule formamide (NH2_{2}CHO) in the envelope of IRAS 18089-1732. We have detected the vv = 0 and 1 states rotational emission lines of CH3_{3}OCHO. We also detected the two vibrationally excited states of HC3_{3}N (vv7 = 1 and vv7 = 2). The estimated fractional abundances of C2_{2}H5_{5}CN, HC3_{3}N (vv7 = 1), HC3_{3}N (vv7 = 2), and NH2_{2}CHO towards the IRAS 18089-1732 are (1.40±\pm0.5)×\times1010^{-10}, (7.5±\pm0.7)×\times1011^{-11}, (3.1±\pm0.4)×\times1011^{-11}, and (6.25±\pm0.82)×\times1011^{-11}. Similarly, the estimated fractional abundances of CH3_{3}OCHO (vv = 0) and CH3_{3}OCHO (vv = 1) are (1.90±\pm0.9)×\times109^{-9} and (8.90±\pm0.8)×\times1010^{-10}, respectively. We also created the integrated emission maps of the detected molecules, and the observed molecules may have originated from the extended envelope of the protostar. We show that C2_{2}H5_{5}CN and HC3_{3}N are most probably formed via the subsequential hydrogenation of the CH2_{2}CHCN and the reaction between C2_{2}H2_{2} and CN on the grain surface of IRAS 18089-1732. We found that NH2_{2}CHO is probably produced due to the reaction between NH2_{2} and H2_{2}CO in the gas phase. Similarly, CH3_{3}OCHO is possibly created via the reaction between radical CH3_{3}O and radical HCO on the grain surface of IRAS 18089-1732.

Keywords

Cite

@article{arxiv.2404.02857,
  title  = {Study of Complex Nitrogen and Oxygen-bearing Molecules toward the High-mass Protostar IRAS 18089$-$1732},
  author = {Arijit Manna and Sabyasachi Pal and Tapas Baug and Sougata Mondal},
  journal= {arXiv preprint arXiv:2404.02857},
  year   = {2024}
}

Comments

Published in Research in Astronomy and Astrophysics