  We developed a new analytical experimental setup called AROMA (Astrochemistry
Research of Organics with Molecular Analyzer) that combines laser
desorption/ionization techniques with ion trap mass spectrometry. We report
here on the ability of the apparatus to detect aromatic species in complex
materials of astrophysical interests and characterize their structures. A limit
of detection of 100 femto-grams has been achieved using pure polycyclic
aromatic hydrocarbon (PAH) samples, which corresponds to 2x10^8 molecules in
the case of coronene (C24H12). We detected the PAH distribution in the
Murchison meteorite, which is made of a complex mixture of extraterrestrial
organic compounds. In addition, collision induced dissociation experiments were
performed on selected species detected in Murchison, which led to the first
firm identification of pyrene and its methylated derivatives in this sample.
