Work

Molecular chemistry induced by a J-shock toward supernova remnant W51C

Year: 2024

Type: article

Abstract: Shock waves from supernova remnants (SNRs) strongly affect the physical and chemical properties of molecular clouds (MCs). \n Shocks propagating into magnetized MCs can be classified into jump or J-shocks and continuous or C-shocks. \n The molecular chemistry in the re-formed molecular gas behind J-shocks is still only poorly understood. It is expected to provide a comprehensive view of the chemical feedback of SNRs and the chemical effects of J-shocks. We conducted a W-band (71.4--89.7 GHz) observation toward a re-formed molecular clump behind a J-shock induced by SNR W51C with the Yebes 40 m radio telescope to study the molecular chemistry in the re-formed molecular gas. Assuming local thermodynamic equilibrium (LTE), we estimated the column densities of and and derived their abundance ratio maps with CO. The gas density was constrained by a non-LTE analysis of the J=1--0 line. The abundance ratios were compared with the values in typical quiescent MCs and shocked MCs, and they were also compared with the results of chemical simulations with the Paris-Durham shock code to verify and investigate the chemical effects of J-shocks. We obtained the following abundance ratios: N( HCO^+ )/N( CO )∼ (1.0 N( HCN )/N( CO )∼ (1.8 N( C_2H )/N( CO )∼ (1.6 and N( o c C_3H_2 )/N( CO )∼ (1.2 . \n The non-LTE analysis suggests that the gas density is n_ H_2 ≳ 10^4 . \n We find that the and are higher than typical values in quiescent MCs and shocked MCs by 1--2 orders of magnitude, which can be qualitatively attributed to the abundant rm C^+ and C in the earliest phase of molecular gas re-formation. The Paris-Durham shock code can reproduce, although not perfectly, the observed abundance ratios, especially the enhanced and with J-shocks propagating into both nonirradiated and irradiated molecular gas with a preshock density of H

Source: Springer Link (Chiba Institute of Technology)

DOI: 10.1051/0004-6361/202452270/pdf

Authors: Tian-Yu Tu, Valentine Wakelam, Yang Chen, Ping Zhou, Qian-Qian Zhang

Institutions: Nanjing University, Centre National de la Recherche Scientifique, Laboratoire d'Astrophysique de Bordeaux

Language: English

Topic: Astrophysics and Star Formation Studies

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: National Natural Science Foundation of China, Centre National d’Etudes Spatiales, Centre National de la Recherche Scientifique, Observatoire de Paris, Université de Recherche Paris Sciences et Lettres

Awards: G2783981541, G7322757637, G7467340691