title: Continuum and discrete pulsed cavity ring down laser absorption spectra of Br2 vapor.
abstract: The absorption cross-sections at room temperature are reported for the first time, of Br2 vapor in overlapping bound-free and bound-bound transition of A(3)pi1u <-- Xsigma(g)+, X(1)pi1u <-- X(1)sigma(g)+ and B(3)pi0u <-- X(1)sigma(g)+, using cavity ring down spectroscopy (CRDS) technique. We reported here, the A(3)pi1u <-- X(1)sigma(g)+, transition is included along with the two stronger X(1)pi1u <-- X(1)sigma(g)+ and B(3)pi0u <-- X(1)sigma(g) transitions of Br2. We obtained discrete absorption cross-section in the rotational structure, the continuum absorption cross-sections, and were also able to measure the absorption cross-section in separate contribution of A(3)pi1u <-- X(1)sigma(g)+, (1)pi1u <-- X(1)sigma(g)+, and B(3)pi0u <-- X(1)sigma(g)+ transitions using CRDS method to use quantum yield of Br*((2)P(1/2)). We obtained absorption cross-section order 10(-19) cm2 and detection 10(13) molecule cm(-3) (1 mTorr) of Br2. The absorption cross-sections are increasing with increasing excitation energy in the wavelength region 510-535 nm.
authors.affiliation: Laser Chemical Physics Laboratory, Engineering Faculty, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan. sharma@chemsys.t.u-tokyo.ac.jp
authors.forename: Ramesh C
authors.initials: RC
authors.lastname: Sharma
authors.forename: Hong-Yi
authors.initials: HY
authors.lastname: Huang
authors.forename: Wang-Ting
authors.initials: WT
authors.lastname: Chuang
authors.forename: King-Chuen
authors.initials: KC
authors.lastname: Lin
mesh_terms: D000042:Absorption; D001965:Bromides / Q000737:chemistry*; D007834:Lasers; D012399:Rotation; D013057:Spectrum Analysis; D013696:Temperature
chemical_list: D001965:Bromides