Detalles de publicación
PP 07017
H2D+ line emission in Proto-Planetary Disk
(1) Instituto de Astrofisica de Canarias
(2) Laboratoire d'Astrophysique de l'Observatoire de Grenoble
(3) Physics & Astronomy Department, University of Kentucky
CONTEXT: Previous studies have indicated that the 372.4 GHz ground transition
of ortho-H2D+ might be a powerful probe of Proto-Planetary Disks. The line
could be especially suited for study of the disk mid-plane, where the bulk of
the mass resides and where planet formation takes place. AIMS: Provide detailed
theoretical predictions for the line intensity, profile and maps expected for
representative disk models. METHODS: We determine the physical and chemical
structure of the disks from the model developed by Ceccarelli & Dominik (2005).
The line emission is computed with the new radiative transfer method developed
recently by Elitzur & Asensio Ramos (2006). RESULTS: We present intensity maps
convolved with the expected ALMA resolution, which delineate the origin of the
H2D+ 372.4 GHz line. In the disk inner regions, the line probes the conditions
in the mid-plane out to radial distances of a few tens of AU, where Solar-like
planetary systems might form. In the disk outermost regions, the line originates
from slightly above the mid-plane. When the disk is spatially resolved, the
variation of line profile across the image provides important information about
the velocity field. Spectral profiles of the entire disk flux show a double peak
shape at most inclination angles. CONCLUSIONS: Our study confirms that the
372.4 GHz H2D+ line provides powerful diagnostics of the mid-plane of
Proto-Planetary Disks. Current submillimeter telescopes are capable of observing
this line, though with some difficulties. The future ALMA interferometer will
have the sensitivity to observe and even spatially resolve the H2D+ line
emission.
of ortho-H2D+ might be a powerful probe of Proto-Planetary Disks. The line
could be especially suited for study of the disk mid-plane, where the bulk of
the mass resides and where planet formation takes place. AIMS: Provide detailed
theoretical predictions for the line intensity, profile and maps expected for
representative disk models. METHODS: We determine the physical and chemical
structure of the disks from the model developed by Ceccarelli & Dominik (2005).
The line emission is computed with the new radiative transfer method developed
recently by Elitzur & Asensio Ramos (2006). RESULTS: We present intensity maps
convolved with the expected ALMA resolution, which delineate the origin of the
H2D+ 372.4 GHz line. In the disk inner regions, the line probes the conditions
in the mid-plane out to radial distances of a few tens of AU, where Solar-like
planetary systems might form. In the disk outermost regions, the line originates
from slightly above the mid-plane. When the disk is spatially resolved, the
variation of line profile across the image provides important information about
the velocity field. Spectral profiles of the entire disk flux show a double peak
shape at most inclination angles. CONCLUSIONS: Our study confirms that the
372.4 GHz H2D+ line provides powerful diagnostics of the mid-plane of
Proto-Planetary Disks. Current submillimeter telescopes are capable of observing
this line, though with some difficulties. The future ALMA interferometer will
have the sensitivity to observe and even spatially resolve the H2D+ line
emission.