New acetylene line list near 3.8-µm - Part I.

• Fourier transform spectroscopy with high absorption path length. • Measured and calculated line positions and intensities for 14 newly observed bands of 12C 2 H 2. • Acetylene line list for the databases near 3.8- μ m. Two acetylene spectra were recorded between 2350 and 2750 cm−1 with Fourier Transform Spectrometer (FTS) using high optical path length. 14 bands were observed for the first time including one cold band. The positions and the intensities of the lines have been measured for 824 transitions of the 12C 2 H 2 isotopologue. The band centers, the band strengths, the upper level spectroscopic constants and the Herman-Wallis parameters were retrieved for all bands. The effective dipole moment parameters of the Δ P = 4 region were refined, P being the polyad number defined as P = 5 V 1 + 3 V 2 + 5 V 3 + V 4 + V 5 , where V i are the vibrational normal mode principal quantum numbers, with i = 1 − 5. An updated line list for the ∆P = 4 series of transitions is proposed as supplementary data in order to improve the spectroscopic databases such as HITRAN or GEISA. [ABSTRACT FROM AUTHOR]