Absorption of pulsed CO(2)-laser radiation by SF(6) at 140 K

Measurements of absorption of pulsed CO(2) laser radiation by SF(6) at 140 K are reported. Four laser frequencies within the nu(3) absorption band were used, and the laser fluence was varied between 10(-5) and 1.0 J/cm(2). Frequency and fluence trends are discussed, and comparisons are made with room-temperature data. The results indicate that at the SF(6) ground-state band center [P(16), 10-microm line], the fluence-dependent multiple-photon-absorption cross-section curve at 140 K lies slightly above the room-temperature curve, whereas at lower frequencies the low-temperature absorption cross sections are less than 5% of the room-temperature values.