Letter to the Editor

The IC1396N proto-cluster at a scale of ~250 AU^*

¹ Institut de Radioastronomie Millimétrique, 300 rue de la Piscine, 38406 St Martin d'Hères Cedex, France e-mail: neri@iram.fr
² Observatorio Astronómico Nacional (OAN), Apdo. 112, 28803 Alcalá de Henares (Madrid), Spain
³ Laboratoire d'Astrophysique de l'Observatoire de Grenoble, BP 53, 38041 Grenoble Cedex 9, France
⁴ Osservatorio Astrofisico di Arcetri (INAF), Largo E. Fermi 5, 50125 Firenze, Italy
⁵ Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 0213, USA
⁶ Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 1A1, Canada
⁷ National Research Council of Canada, Herzberg Institute, 5071 West Saanich Road, Victoria, BC V9E 2E7, Canada
⁸ Leiden Observatory, PO Box 9513, 2300 RA Leiden, The Netherlands
⁹ Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
¹⁰ University of Calgary, 2500 University Drive NW, Alberta T2N 1N4, Canada

Received: 16 February 2007
Accepted: 12 April 2007

Abstract

Aims.We investigate the mm-morphology of IC 1396 N with unprecedented spatial resolution to analyze its dust and molecular gas properties, and draw comparisons with objects of similar mass.

Methods.We have carried out sensitive observations in the most extended configurations of the IRAM Plateau de Bure interferometer, to map the thermal dust emission at 3.3 and 1.3 mm, and the emission from the hyperfine transitions of methyl cyanide (CH₃CN).

Results.We unveil the existence of a sub-cluster of hot cores in IC 1396 N, distributed in a direction perpendicular to the emanating outflow. The cores are embedded in a common envelope of extended and diffuse dust emission. We find striking differences in the dust properties of the cores () and the surrounding envelope (), very likely testifying to differences in the formation and processing of dust material. The CH₃CN emission peaks towards the most massive hot core and is marginally extended in the outflow direction.