| Authors||T.A. van Kempen, J.D. Green, N.J. Evans II, E.F. van Dishoeck, L.E. Kristensen, G.J. Herczeg, B. Merín, J.-E. Lee, J.K. Jørgensen, J. Bouwman, B. Acke, M. Adamkovics, J.C. Augereau, E. Bergin, G.A. Blake, J.M. Brown, J.S. Carr, J.-H. Chen, L. Cieza, C. Dominik, C.P. Dullemond, M.M. Dunham, A. Glassgold, M. Güdel, P.M. Harvey, T. Henning, M.R. Hogerheijde, D. Jaffe, H.J. Kim, C. Knez, J.H. Lacy, S. Maret, G. Meeus, R. Meijerink, G.D. Mulders, L. Mundy, J. Najita, J. Olofsson, K.M. Pontoppidan, C. Salyk, B. Sturm, R. Visser, L.B.F.M. Waters, C. Waelkens, U.A. Yıldız|
|Title||Dust, Ice, and Gas In Time (DIGIT) Herschel program first results: A full PACS-SED scan of the gas line emission in protostar DK Chamaeleontis|
|Journal||Astronomy & Astrophysics|
|Faculty||Faculty of Science|
|Institute/dept.||FNWI: Astronomical Institute Anton Pannekoek (IAP)|
|Abstract||Aims. We aim to study the composition and energetics of the circumstellar material of DK Cha, an intermediate-mass star in transition from an embedded configuration to a star plus disk stage, during this pivotal stage of its evolution.|
Methods. Using the range scan mode of PACS on the Herschel Space Observatory, we obtained a spectrum of DK Cha from 55 to 210 mu m as part of the DIGIT key program.
Results. Almost 50 molecular and atomic lines were detected, many more than the 7 lines detected in ISO-LWS. Nearly the entire ladder of CO from J = 14-13 to 38-37 (E-u/k = 4080 K), water from levels as excited as J(K-1K+1) = 7(07) (E-u/k = 843 K), and OH lines up to E-u/k = 290 K were detected.
Conclusions. The continuum emission in our PACS SED scan matches the flux expected by a model consisting of a star, a surrounding disk of 0.03 M-circle dot, and an envelope of a similar mass, supporting the suggestion that the object is emerging from its main accretion stage. Molecular, atomic, and ionic emission lines in the far-infrared reveal the outflow's influence on the envelope. The inferred hot gas may be photon-heated, but some emission may be caused by C-shocks in the walls of the outflow cavity.
Use this url to link to this page: http://dare.uva.nl/en/record/374446
Contact us about this recordNotify a colleague
Add to bookbag