A candidate circumbinary Keplerian disk in G35.20-0.74 N:
A study with ALMA

Á. Sánchez-Monge, R. Cesaroni, M. T. Beltrán, M. S. N. Kumar, T. Stanke, H. Zinnecker, S. Etoka, D. Galli, C. A. Hummel, L. Moscadelli, T. Preibisch, T. Ratzka, F. F. S. van der Tak, S. Vig, C. M. Walmsley, K.-S. Wang

Abstract
We report on ALMA observations of continuum and molecular line emission with 0''.4 resolution towards the high-mass star-forming region G35.20–0.74 N. Two dense cores are detected in typical hot-core tracers (e.g., CH₃CN) that reveal velocity gradients. In one of these cores, the velocity field can be fitted with an almost edge-on Keplerian disk rotating about a central mass of ~18 M_☉. This finding is consistent with the results of a recent study of the CO first overtone bandhead emission at 2.3 µm towards G35.20–0.74 N. The disk radius and mass are ≳2500 au and ~3 M_☉. To reconcile the observed bolometric luminosity (~3×10⁴ L_☉) with the estimated stellar mass of 18 M_☉, we propose that the latter is the total mass of a binary system.

Keywords
stars: formation – ISM: individual objects: G35.20-0.74N – ISM: jets and outflows

Notes
Estimate taken from the rms database, available at http://www.ast.leeds.ac.uk/cgi-bin/RMS/RMS_DATABASE.cgi

Astronomy and Astrophysics
Volume 552, Page L10_1
April 2013

DOI: 10.1051/0004-6361/201321134
ADS Bibliographic code: 2013A%26A...552L..10S