Stabilized Tunable Diode Laser Measurements of the P(2) Line in the 13CO Fundamental Band Broadened by Helium at Temperatures between 11.5 and 298.6 K

We determined accurate He-broadening parameters and collisional cross sections for the P(2) line in the fundamental band of CO at room temperature and at intermediate temperatures down to 11.5 K. We also determined a precise value for the temperature dependence of the line-broadening parameter on (T)−nwith nequal to 0.548±0.010. Our results validate the microwave results for the J=1 to J=2 rotational transitions measured over the same range of temperatures which were reported previously by Beaky et al.(1996, J. Chem. Phys.105, 3994–4004).