A Comparison of c-C3H2 and l-C3H2 in the Spiral Arm Clouds

M. Kulczak-Jastrzebska (1) , Darek C. Lis (2) , Maryvonne Gerin (3, 4)

1 Astronomical Observatory, Jagiellonia University
2 Cahill Center for Astronomy and Astrophysics
3 LERMA - Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique
4 Dynamique des milieux interstellaires et plasmas stellaires

Using the IRAM 30-m telescope, we observed molecular absorption lines from c-C<SUB>3</SUB>H<SUB>2</SUB> produced in diffuse clouds toward the high-mass star forming regions W51 e1/e2 and W49N to determine the abundance ratio between the cyclic and linear isomers of C<SUB>3</SUB>H<SUB>2</SUB> (N<SUB>c</SUB>/N<SUB>l</SUB>). The abundance ratio is found to be 3-5 in the sources where l-C<SUB>3</SUB>H<SUB>2</SUB> was previously detected. A possible source of uncertainty in the determination of N<SUB>c</SUB>/N<SUB>l</SUB> is related to the estimate of N(c-C<SUB>3</SUB>H<SUB>2</SUB>). The main goal of this paper is verification of this hypothesis.

Domaines: Astrophysique [astro-ph]

M. Kulczak-Jastrzebska, Darek C. Lis, Maryvonne Gerin. A Comparison of c-C3H2 and l-C3H2 in the Spiral Arm Clouds. Acta Astronomica, 2012, 62, pp.313-321. ⟨hal-03732716⟩