The Astrophysical Journal · 1989 · 858 citations · 0 references
Natural SciencesAstronomyPhysicsAstrophysicsInfrared AstronomyPhysical ChemistryInterstellar ChemistryInterstellar GasInterstellar MoleculesMolecular CloudsMolecular CollisionsMolecular Formation PathwaysDense Molecular GasInfrared EmissionInfrared Emission SpectraInfrared SpectraInterstellar Molecule FormationInterstellar ShocksMolecular Formation In Interstellar CloudsMolecule Formation In Molecular Clouds
The study investigates the structure and emission spectrum of J shocks in molecular gas across a wide range of conditions. The authors model J shocks in molecular clouds to analyze their structure and emission spectrum. At high densities, chemistry strongly shapes the emission spectrum, producing a H₂ formation plateau that heats the gas and drives endothermal reactions that generate warm H₂, CO, OH, H₂O, and enhanced warm atoms and ions, with the resulting heat radiated in collisionally excited atomic fine‑structure lines. Published in The Astrophysical Journal, July 1989 (DOI 10.1086/167595).
view Abstract Citations (906) References (113) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Molecule Formation and Infrared Emission in Fast Interstellar Shocks. III. Results for J Shocks in Molecular Clouds Hollenbach, David ; McKee, Christopher F. Abstract The structure and emission spectrum of J shocks in molecular gas are studied over a broad range of conditions. It is found that at high densities chemistry has a profound effect on the emission spectrum: the density behind the shock is sufficiently high that some of the internal energy of the newly formed H2 molecules is transformed to the gas as heat by collisional deexcitations, producing the H2 formation plateau. In this temperature plateau, endothermal reactions and neutral-neutral chemical reactions with activation energies can proceed efficiently, producing significant quantities of warm H2, CO, OH, and H2O and enhanced columns of warm atoms and ions. The heat generated by the H2 formation is radiated in collisionally excited atomic fine-structure lines. Publication: The Astrophysical Journal Pub Date: July 1989 DOI: 10.1086/167595 Bibcode: 1989ApJ...342..306H Keywords: Emission Spectra; Infrared Sources (Astronomy); Interstellar Chemistry; Molecular Clouds; Shock Fronts; Cosmic Rays; Fine Structure; Herbig-Haro Objects; Molecular Gases; Supernova Remnants; Water Masers; Astrophysics; INTERSTELLAR: GRAINS; INTERSTELLAR: MOLECULES; MOLECULAR PROCESSES; SHOCK WAVES full text sources ADS | data products SIMBAD (2)