caa a22 4500 445369930 CHVBK 20180317142943.0 cr unu---uuuuu 170323e20110901xx s 000 0 eng 10.1007/s00340-011-4546-8 doi (NATIONALLICENCE)springer-10.1007/s00340-011-4546-8 Influence of oxygen on the resonant photoacoustic signal from methane excited at the ν 3 mode [Elektronische Daten] [N. Barreiro, A. Vallespi, G. Santiago, V. Slezak, A. Peuriot] This paper shows that, when samples of methane in dry air are irradiated with an OPO tuned at the ν 3 mode at 3019cm−1, the photoacoustic signal is lower than in mixtures in pure nitrogen. In order to explain this change, we developed a rate-equation-based model which describes the methane excitation and relaxation to heat by collisions with the buffer. In particular, we reduced the problem to a system of six energy levels taking into account the fast energy exchange between methane and oxygen resonant states and the slow relaxation rate of oxygen. Thus, the photoacoustic signal is calculated for methane-nitrogen and methane-air systems and a very good agreement is found with the experimental results. Springer-Verlag, 2011 Barreiro N. Centro de Investigaciones en Laseres y Aplicaciones CEILAP (CITEFA-CONICET), Juan Bautista de La Salle 4397, 1603, Villa Martelli, Argentina aut Vallespi A. Centro de Investigaciones en Laseres y Aplicaciones CEILAP (CITEFA-CONICET), Juan Bautista de La Salle 4397, 1603, Villa Martelli, Argentina aut Santiago G. Laboratorio Láser, Facultad de Ingeniería, Universidad de Buenos Aires, Paseo Colón 850, 1063, Buenos Aires, Argentina aut Slezak V. Centro de Investigaciones en Laseres y Aplicaciones CEILAP (CITEFA-CONICET), Juan Bautista de La Salle 4397, 1603, Villa Martelli, Argentina aut Peuriot A. Centro de Investigaciones en Laseres y Aplicaciones CEILAP (CITEFA-CONICET), Juan Bautista de La Salle 4397, 1603, Villa Martelli, Argentina aut Applied Physics B Springer-Verlag 104/4(2011-09-01), 983-987 0946-2171 104:4<983 2011 104 340 https://doi.org/10.1007/s00340-011-4546-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00340-011-4546-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Barreiro N. Centro de Investigaciones en Laseres y Aplicaciones CEILAP (CITEFA-CONICET), Juan Bautista de La Salle 4397, 1603, Villa Martelli, Argentina aut NATIONALLICENCE 700 1- Vallespi A. Centro de Investigaciones en Laseres y Aplicaciones CEILAP (CITEFA-CONICET), Juan Bautista de La Salle 4397, 1603, Villa Martelli, Argentina aut NATIONALLICENCE 700 1- Santiago G. Laboratorio Láser, Facultad de Ingeniería, Universidad de Buenos Aires, Paseo Colón 850, 1063, Buenos Aires, Argentina aut NATIONALLICENCE 700 1- Slezak V. Centro de Investigaciones en Laseres y Aplicaciones CEILAP (CITEFA-CONICET), Juan Bautista de La Salle 4397, 1603, Villa Martelli, Argentina aut NATIONALLICENCE 700 1- Peuriot A. Centro de Investigaciones en Laseres y Aplicaciones CEILAP (CITEFA-CONICET), Juan Bautista de La Salle 4397, 1603, Villa Martelli, Argentina aut NATIONALLICENCE 773 0- Applied Physics B Springer-Verlag 104/4(2011-09-01), 983-987 0946-2171 104:4<983 2011 104 340 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer