Laboratory Mass Spectrometry Facility TNA 7 and JRA 15 Activity PI: R. Thissen (LPG, Grenoble, France) List of laboratories: - LPG (Grenoble, France) - LCBOB (Paris, France) - IOCB (Prague, Czech Republic) - AMPL (Trento, Italy)

2 / 11 Description of the proposed infrastructure activity Bring to planetary sciences community expertise of physical chemists in mass spectrometry Offer to planetary sciences community access to a Facility with top-grade mass spectrometers distributed in different laboratories in Europe

3 / 11 Mass spectrometers with sophisticated characteristics Very high resolution mass spectrometry (Fourier Transform MS with resol ) Gas or liquid chromatography coupled with mass spectrometry (GC-MS, LC-MS) Pyrolysis coupled with GC-MS (solid samples) MS/MS analysis and D/H exchange (chemical structure of molecules) Different sources for introduction of gas and liquid (soluble extract) samples

4 / 11 Example: MS/MS study chemical structure analysis of tholins MS/MS of CxHyNz + fragment ions obtained from tholins (laboratory analogues of Titan aerosols) Somogyi et al. JACS (2005) -HCN -CH 2 NH 2 -NH 3 Collision induced dissociation of mass-selected ions

5 / 11 Specific contribution to EuroPlaNet I3 Mass Spectrometry Facility = network of European top-grade MS instruments for Planetary Sciences Bring together MS physical chemist expertise for interpretation of space data on complex molecular species chemical sample analysis Question: common integrated activity with Mass Spectrometers for solid sample analysis? (see B. Marty’s talk)

6 / 11 TNA and JRA with budget TNA (520 keuros) Travel costs for external users Mass Spectrometers operation costs (20% of time operation for external users) Postdoc positions JRA (600 keuros) Improvements of the mass spectrometer sources (ex: development of a VUV continuum source)

7 / 11

8 / 11  Important molecular synthesis, even at 1200 km altitude  Mass spectrum up to 100  Mass resolution limited to 1  Modelisation is essential to identify CxHyNz + ions m/z 68 C 5 H 8 + C 3 H 4 N 2 + Cassini mass spectrometer (INMS) First results (April 2005) complex CxHyNz + ions !

9 / 11 Example: what are the CxHyNz + ions observed by INMS on Cassini in Titan ionosphere?  CxHyNz + can have the same nominal mass as C(x+1)H(y+2)N(z-1) + as CH 2 has the same mass as N Ex: m/z 173 C 11 H 13 N 2 + or C 13 H > needs very high mass resolution  CxHyNz + ions correspond to many possible isomers --> needs for structural/functional analysis  Reactions forming CxHyNz + ions are not well known --> what is the growth chemical scheme and where does it stop?

10 / 11 New experimental set-up: MS/MS High Resolution Mass spectrom Reactions

11 / 11 High mass resolution? Example of cigarette smoke analysis Resolution: 6000 Resolution: 12000

12 / 11 The « underestimated channels » active synthesis of neutral molecules Vuitton et al NH 3 CH 2 NH CH 3 CN C 2 H 3 CN C 2 H 5 CN Assuming that the missing peaks correspond to protonated, N- containing molecules, ion densities allow To propose a density for neutral molecules, totally Unexptected at such high altitudes and revealing a process of neutral syntheses in the ionosphere

13 / 11 many reactions are missing Result of the uncertainty propagation Carrasco et al, Planet. Space Sci. 2006, in press Cassini INMS mass spectrum Simulated mass spectrum Ionospheric model of M. Banaszkiewicz et al. Icarus (2000) Uncertainties on rate constants and branching ratios Same simulated spectrum with 248 reactions instead of 584 ! 1200 km strongly underestimated HCNH +