Laboratory characterization and astrophysical detection in Orion KL of higher excited states of vinyl cyanide Alicia Lopez, a Belen Tercero, a Jose Cernicharo, a Zbigniew Kisiel, b Lech Pszczółkowski, b Celina Bermudez, c Jose L.Alonso, c Ivan R.Medvedev, d Christopher Neese e, Brian J.Drouin, f Adam M.Daly, f Nuria Marcelino, g Serena Viti, h Hannah Calcutt, h a Departamento de Astrofısica, Centro de Astrobiologia CAB, CSIC-INTA, Madrid, Spain b Institute of Physics, Polish Academy of Sciences, Warszawa, Poland c Grupo de Espectroscopia Molecular, Universidad de Valladolid, Valladolid, Spain d Department of Physics, Wright State University, Dayton, OH 45435, USA e Department of Physics, The Ohio State University, Columbus, OH 43210, USA f Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA g ALMA, National Radio Astronomy Observatory, Charlottesville, VA, USA h Department of Physics and Astronomy, University College London, UK 69th International Symposium on Molecular Spectroscopy WF11

Rotational spectroscopy of acrylonitrile: Recent laboratory papers:  revised:Krasnicki+Kisiel,, J.Mol.Spectrosc. 270, 83 (2011) isotopic+struct:Krasnicki et al., J.Mol.Struct. 1006, 20 (2011) gs to 2 11 :Kisiel et al., J.Mol.Spectrosc. 280, 134 (2012) Planar (C s ), relatively rigid molecule, positioned in the ab inertial plane  a = 3.821(3) D  b = 0.687(8) D Class 2 astrophysical weed as of 2006 ! Some relevant astrophysical papers: first astro, Sgr B2:Gardner+Winnewisser, Astrophys.J.. 195, L127 (1975) isot. in Sgr B2:Muller et al., J.Mol.Spectrosc. 251, 319 (2008) isot.+es. Sgr B2:Belloche at al., A&A 559, A (2013)

The acrylonitrile rotational spectrum:  a type transitions  b type transitions updated spectra used in this work

The recorded spectra: Multiplier of cmw-region pump frequency in cascaded multiplication GHz

Analysis: AABS package + Pickett’s SPFIT/SPCAT  Spectrum handling: single spectrum 0.05 MHz) + modified baseline subtraction  Loomis-Wood displays: assignment  Difference-frequency plots: location of pairwise perturbations  Distribution plots: essential book-keeping for large data sets AABS = A ssignment and A nalysis of B roadband S pectra, available at:

Our previous work on the THz-level spectrum of acrylonitrile: J.Mol.Spectrosc. 2009: g.s.  11 perturbations J.Mol.Struct. 2011: g.s.  11 perturbations in isotopic acrylonitrile J.Mol.Spectrosc. 2012: g.s.  11  15  2 11 fit g.s.  11  15  2 11 fit TH10, OSU symposium 2012: 10  fit 10  fit

Vibrational levels of vinyl cyanide up to 1000 cm -1 All states marked in red have been studied in this work Rectangles identify polyads of vibrational states treated in terms of coupled fits

The Stark-modulation spectrum of the 4 13 ← 3 12 transition: 4 13 ← 3 12 Each marked line corresponds to the 4 13 ← 3 12 transition in either an excited state of the parent species or an isotopic ground state - note the characteristic lineshape Analysed in the current work States in a coupled fit  detected in Orion-KL

Summary of fits: Consistent set of vibrational energies derived by taking advantage of the results of the perturbation analyses and calculated anharmonicity coefficients Made with a block diagonal Hamiltonian as required by the C s symmetry of vinyl cyanide with either a-type+b-type Coriolis or c-type Coriolis+Fermi off- diagonal blocks ( details: Kisiel et al.,, J.Mol.Spectrosc. 280, 134 (2012) )

Perturbations in lowest K a, a R-type transitions Perturbation magnitude:  2700 MHz (45x60) Perturbations are within blocks for a given value of J Mirror image difference frequency plots relative to the ground state for two vibrational states identify perturbing K a sequences. Take-home message: in cases like these it is mandatory to account for perturbations, otherwise linelists will not correctly predict key transitions that may be searched for K a +K c =J +1 K a +K c = J

Spectroscopic constants: a-axis Coriolis b-axis Coriolis

Confirmation of vibrational assignment by (B v -B 0 ) values: different anharmonic force field calculations using summation of single excitation vibrational changes ABCABC

Observed  11 =1 lines (228 cm -1 ) in Orion KL: Vinyl cyanide Complete model (MADEX) IRAM-30m, 9 adjacent panels out of a much larger selection

Observed  11 =2 lines (457 cm -1 ) in Orion KL: Vinyl cyanide Complete model

Observed 10  dyad (560 cm -1 ) lines in Orion KL: Observed 10  11, 15 dyad (560 cm -1 ) lines in Orion KL: Vinyl cyanide Complete model

Vinyl cyanide Complete model Observed 13 C vinyl cyanide lines in Orion KL:

 The coverage of the room temperature rotational spectrum of acrylonitrile has been increased in extent to a total of 1248 GHz corresponding to 65.7% of the range up to the upper frequency limit to 1.9 THz  Continuous coverage of the GHz region  Broadband coverage turned out to be crucial to locating specific pairwise perturbations between vibrational states 10   Coupled fits of: 10  11, 15 dyad ( 3972 lines) 2 15  14   14  3 11 triad ( 3866 lines) 10  11   11  2 11, 15 dyad ( 1702 lines)  Laboratory data and linelists at  Astrophysical part of this investigation reports a massive amount of data on Orion-KL: column densities, abundances, rotational plots, intensity maps, other molecules (including vinyl isocyanide), soon in A&A?SUMMARY: