中文摘要：

基于气体谱线展宽理论,数值模拟了甲烷泛频带2ν3的R（9）支吸收线型。利用可调谐半导体激光器从实验上测量了甲烷2ν3的R（9）支吸收线型。通过扫描1637.6～1637.92 nm甲烷混合气体的吸收光谱,计算得到甲烷自展宽系数（0.0725±0.008）cm-1/atm,空气碰撞加宽系数为（0.0335±0.0012）cm-1/atm。并首次从理论上给出了甲烷1637.8 nm吸收峰中心波长,在标准大气压条件下,随甲烷浓度变化的关系。对提高激光调制技术测量气体精度,具有重要意义。

英文摘要：

Based on analyzing the infrared absorption spectrum of methane,we present the study on line profile of methane 2ν_3 overtone band R9 branch 1637.83 nm absorption peak by using a tunable diode laser.The self-broadening and air-broadening coefficients of global profile are（0.0725±0.008） cm-1/atm and（0.0335±0.0012） cm-1/atm respectively.Peak center position of R9 branch 1637.83 nm shifting with different ratio of methane and air under one atmosphere pressure is worked out.It is of important value in heightening the gas measurement precision with modulated laser.