Knowledge Bank

Several improvements have been made on the apparatus developed in Brussels for the study of jet-cooled molecules, named \hbox{FANTASIO nderline{\textbf{105}}(5-7), 815 (2007).} nderline{\textbf{463}}, 345 (2008).} nderline{\textbf{113}}, 2359 (2009).}}, for "Fourier trANsform, Tunable, diode and quadrupole mAss spectrometers interfaced to a Supersonic expansIOn". The upgraded setup, called Femto-FANTASIO, is presented.\ These improvements include: a doubling of the pumping efficiency, by adding another turbomolecular pump Leybold MAG-W3200 CT; an increase in sensitivity in the 1.5 $\mu$m range thanks to a new CRDS system, consisting in new cavity mirrors, leading to a ring down time of 125 $\mu$s and a new detector, decreasing the noise level; a new injection system to probe samples liquid at STP conditions; a temperature controlled nozzle/slit; and as an alternative probe technique, an absorption source, tunable from 3000 to 9000 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$, coupling an optical parametric oscillator (OPO), pumped by a Ti:Sa femtosecond laser, to a high resolution continuous scan Fourier transform interferometer.\ Femto FANTASIO will be used to investigate molecular complexes. First results and achievements of this new setup are presented.