15min:

HOLGER S. P. MÜLLER, I. Physikalisches Institut, Universität zu Köln, 50937 Köln; and Max-Planck-Institut für Radioastronomie, 53121 Bonn, Germany; A. COUTENS, A. WALTERS, CESR, Université de Toulouse (UPS), and CNRS, 31028 Toulouse, France; J.-U. GRABOW, Institut für Physikalische Chemie und Elektrochemie, Lehrgebiet A, Universität Hannover, 30167 Hannover, Germany; A. BELLOCHE, K. M. MENTEN, Max-Planck-Institut für Radioastronomie, 53121 Bonn, Germany; S. SCHLEMMER, I. Physikalisches Institut, Universität zu Köln, 50937 Köln, Germany.

We have carried out a molecular line survey of Sagittarius B2(N) in the 3 mm region with selected recordings at 2 and 1.3 mm to probe the chemical complexity in massive star-forming regions. Noteworthy results include the detection of aminoacetonitrile,\footnoteA.~Belloche, K.~M.~Menten, C.~Comito, H.~S.~P. Müller, P.~Schilke, J.~Ott, S.~Thorwirth, C.~Hieret, Astron. Astrophys. 482 (2008) 179; Erratum 492 (2008) 796. a possible precursor of the aminoacid glycine, the detection of ¹³C isotopologs of vinyl cyanide, and the detection of ethyl formate as well as normal-propyl cyanide. The heavy atoms in the latter molecule form a chain. An isomer with a branched structure, iso-propyl cyanide, also exists, but its rotational spectrum has only been recorded in few transitions up to 40 GHz. Therefore, laboratory measurements were extended. The molecule is rather asymmetric ( = -0.5766) with a strong a-dipole moment component of 4.05~(2)~D and a still sizable c-component of 1.4~(2)~D.^e Measurements in Köln were carried out in selected regions between 40 and 600 GHz. Since the c-type transitions appeared to be weaker than predicted additional Stark (and also zero-field) measurements have been carried out in Hannover between 6 and 20 GHz. We will present results of these laboratory spectroscopic investigations as well as the outcome of a search for the molecule in our Sgr B2(N) line survey.