Transition dipole-moment of the ν₁+ν₃ band of acetylene measured with dual-comb Fourier-transform spectroscopy

The ν₁+ν₃ vibration band of acetylene (C₂H₂) in the near infrared region was recorded with a dual-comb Fourier-transform spectrometer. We observed 56 transitions from P(26) to R(29) at six different column densities. The integral line intensity was determined for each recorded absorption line by fitting the line profile to Lambert-Beer's law with a Voigt function. Thanks to the outstanding capability of dual-comb spectroscopy to cover a broad spectrum in a relatively short time with high resolution and high frequency precision, we determined the reliable line strength for each ro-vibrational transition as well as the transition dipole moment for this band.