Diode laser measurements of linestrength and temperature-dependent lineshape parameters of H2O-, CO2-, and N2-perturbed H2O transitions near 2474 and 2482 nm

- Linestrengths were measured for 17 high-J H2O transitions near 2474 and 2482 nm.
- Lineshape parameters were measured for two H2O doublets at 650-1325 K.
- Voigt and Galatry lineshape parameters are quoted for H2O, CO2 and N2 perturbers.
- N2-broadening and -narrowing coefficients exhibit opposite temperature dependence.
- CO2-broadening and -narrowing coefficients decreased with increasing temperature.

Absorption lineshapes for two unresolved H2O doublets near 4029.52 and 4041.92 cm−1 were measured at high-resolution in a heated static cell using two distributed-feedback diode lasers. Measurements were acquired for H2O, CO2, and N2 perturbers over a temperature and pressure range of 650-1325 K and 2-760 Torr, respectively. Strong collisional narrowing effects were observed in CO2 and N2, but not in pure H2O. The Galatry profile was used to infer collisional-broadening and -narrowing coefficients and their respective temperature dependence for CO2 and N2 perturbers. The collisional-broadening and -narrowing coefficients for CO2 perturbers were found to decrease with increasing temperature in a similar manner. For N2 perturbers, the collisional-broadening coefficients increased with temperature while the collisional-narrowing coefficients decreased with increasing temperature. Self-broadening coefficients were inferred from Voigt profile fits and are compared with HITEMP 2010. The linestrengths of 17 H2O transitions are also reported.