title: Absorption cross sections for the A 2A'' (0,9(0),0) <-- X 2A' (0,0(1),0) band of the HCO radical.
abstract: Absorption cross sections for the A 2A'' (0,9(0),0) <-- X 2A' (0,0(1),0) band of HCO were determined at 295 K using pulsed laser photolysis combined with cavity ring-down spectroscopy. Formyl radicals (HCO) were produced from the reaction of atomic chlorine, generated by photolysis of Cl2 at 335 nm, with formaldehyde. The concentration of HCO was calibrated using two independent photochemical methods. The peak cross section of the P8 line was determined to be (1.98 +/- 0.36) x 10(-18) cm2, and the intensity of the entire band was normalized to this line. The quoted 2 sigma uncertainty includes estimated systematic errors. Comparisons to previously reported values of HCO cross sections in this band are discussed.
authors.affiliation: NOAA Earth System Research Laboratory, Chemical Sciences Division, 325 Broadway, Boulder, CO 80305-3328, USA. steven.s.brown@noaa.gov
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Flad
authors.forename: Steven S
authors.initials: SS
authors.lastname: Brown
authors.forename: James B
authors.initials: JB
authors.lastname: Burkholder
authors.forename: Harald
authors.initials: H
authors.lastname: Stark
authors.forename: A R
authors.initials: AR
authors.lastname: Ravishankara
mesh_terms: D000042:Absorption; D002713:Chlorine / Q000737:chemistry; D005557:Formaldehyde / Q000737:chemistry*; D005609:Free Radicals / Q000737:chemistry*; D010126:Ozone / Q000737:chemistry; D010777:Photochemistry; D010782:Photolysis; D013997:Time Factors
chemical_list: D005609:Free Radicals; D005557:Formaldehyde; D002713:Chlorine; D010126:Ozone