The Physical Structure of a Prestellar Core in IC 5146

Carsten Kramer, João Alves, Charles Lada

Publications: Contribution to bookContribution to proceedings


We observed an evenly sampled map of the 3 P 1-3 P 0 line of neutral atomic carbon in a 0.5 x 0.5 pc2 quiescent, dark core region of IC 5146 immersed in the interstellar radiation field. For comparison at the same spatial resolution of 0.067 pc, we mapped in addition the emission of 13CO 2-1, and, previously, of C18O 2-1 and A_V. The evenly sampled map of A_V was created by Lada et al. [14] from NIR pencil beam observations towards background stars. We find that C I and 13CO 2-1 line intensities are well correlated reflecting their similar line shapes. In contrast to C18O, their integrated intensities stay almost constant with extinctions and are poorly correlated. We argue that this is indicative of unresolved small scale structure and use a spherical symmetric model of photon dominated regions (PDRs) to study the emergent line intensities. The observations are consistent with a large number of small clumps having radii of e.g. 760 AU, masses of 10-3 M_{⊙} and surface densities of 105 cm-3. The volume filling factor is ˜10%.
Original languageEnglish
Title of host publicationThe Origin of Stars and Planets: The VLT View
Subtitle of host publicationProceedings of the ESO Workshop Held in Garching, Germany, 24-27 April 2001
EditorsJoão F. Alves , Mark J. McCaughrean
Place of PublicationBerlin
PublisherSpringer-Verlag Berlin-Heidelberg
ISBN (Electronic)978-3-540-46031-2
ISBN (Print)978-3-540-43541-9
Publication statusPublished - 2002

Publication series

SeriesESO Astrophysics Symposia

Austrian Fields of Science 2012

  • 103004 Astrophysics

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