H_{2}S Formation in Dark Clouds

D. G. Navarro , A. Fuente (1) , P. Caselli (2) , M. Gerin (3) , C. Krammer , E. Rouef , Valentine Wakelam (4) , T. Alonso-Albi (1) , R. Bachiller , S. Cazaux (5) , B. Commerçon (6) , R. Friesen , S. Garcia-Burillo (7) , B. M. Giuliano , J. R. Goicoechea (3) , P. Gratier (4) , A. Hacar , I. Jimenez-Serra (8) , J. Kirk (9) , V. Lattanzi , J. C. Loison (10) , P. J. Malinen , N. Marcelino (11) , R. Martín-Doménech , G. Muñoz-Caro , J. Pineda (12) , M. Tafalla (13) , B. Tercero (14) , D. Ward-Thompson (9) , S. Treviño-Morales (15) , P. Riviere-Marichalar (16) , O. Roncero (17) , Thomas Vidal (4)

1 Observatorio Astronomico Nacional, Madrid
2 OAA - INAF - Osservatorio Astrofisico di Arcetri
3 LERMA - Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique
4 AMOR 2019
5 CEA - Commissariat à l'énergie atomique et aux énergies alternatives
6 CRAL - Centre de Recherche Astrophysique de Lyon
7 OAN, Madrid
8 QMUL - Queen Mary University of London
9 School of Physics and Astronomy [Cardiff]
10 ISM - Institut des Sciences Moléculaires
11 OABO - INAF - Osservatorio Astronomico di Bologna
12 LRP - Laboratoire de Radiopathologie
13 FL - foreign laboratories
14 ICMM - Instituto de Ciencia de Materiales de Madrid
15 Instituto de Radio Astronomía Milimétrica
16 Departamento de Astrofisica [Madrid]
17 CSIC - Consejo Superior de Investigaciones Cientificas [España] = Spanish National Research Council [Spain]

Sulfur is of fundamental importance in a wide variety of phenomena such as life on Earth. This element is one of the most abundant elements in space S/H ˜ 1.3×10^{-5}, but sulfuratted molecules are not as abundant as expected, thus a better understanding of sulfur chemistry is needed. We study and model the abundance of H_{2}S in two prototypical dark clouds, TMC1 and Barnard 1, to shed light on the physical and chemical processes involved in H_{2}S creation and destruction. Our observations are consistent with a PDR model in which H_{2}S is formed in grain mantles and released to gas phase via photodesorption. We cannot discard the contribution of other desorption processes, such as chemical desorption and/or grain-grain collisions, to enhance the H_2S abundance.

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]

D. G. Navarro, A. Fuente, P. Caselli, M. Gerin, C. Krammer, et al.. H_{2}S Formation in Dark Clouds. Highlights on Spanish Astrophysics X, Proceedings of the XIII Scientific Meeting of the Spanish Astronomical Society held on July 16-20, 2018, in Salamanca, Spain, ISBN 978-84-09-09331-1. B. Montesinos, A. Asensio Ramos, F. Buitrago, R. Schödel, E. Villaver, S. Pérez-Hoyos, I. Ordóñez-Etxeberria (eds.) p. 366-373, Jul 2018, Salamanque, Spain. ⟨hal-02051765⟩