Characterising the high-mass star forming filament G351.776–0.527 with Herschel and APEX dust continuum and gas observations^★,★★

¹ INAF – Osservatorio Astronomico di Cagliari, Via della Scienza 5, 09047 Selargius (CA), Italy
e-mail: silvia.leurini@inaf.it
² Istituto di Astrofisica e Planetologia Spaziali – INAF, Via Fosso del Cavaliere 100, 00133 Roma, Italy
³ INAF – Istituto di Radioastronomia, and Italian ALMA Regional Centre, Via P. Gobetti 101, 40129, Bologna, Italy
⁴ Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
⁵ Institute for Astrophysical Research, Boston University, 725 Commonwealth Ave, Boston, MA 02215, USA
⁶ Centre for Astrophysics and Planetary Science, University of Kent, Canterbury CT2 7NH, UK
⁷ School of Physics, University of New South Wales, Sydney, NSW 2052, Australia
⁸ European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748, Garching bei München, Germany
⁹ INAF – Osservatorio Astrofisico di Arcetri, L.go E. Fermi 5, 50125 Firenze, Italy
¹⁰ Excellence Cluster Universe, Boltzmannstr. 2, 85748, Garching bei München, Germany

Received: 11 June 2018
Accepted: 20 November 2018

Abstract

G351.776-0.527 is among the most massive, closest, and youngest filaments in the inner Galactic plane and therefore it is an ideal laboratory to study the kinematics of dense gas and mass replenishment on a large scale. In this paper, we present far-infrared and submillimetre wavelength continuum observations combined with spectroscopic C¹⁸O (2–1) data of the entire region to study its temperature, mass distribution, and kinematics. The structure is composed of a main elongated region with an aspect ratio of ~23, which is associated with a network of filamentary structures. The main filament has a remarkably constant width of 0.2 pc. The total mass of the network (including the main filament) is ≥2600M_⊙, while we estimate a mass of ~2000M_⊙ for the main structure. Therefore, the network harbours a large reservoir of gas and dust that could still be accreted onto the main structure. From the analysis of the gas kinematics, we detect two velocity components in the northern part of the main filament. The data also reveal velocity oscillations in C¹⁸O along the spine in the main filament and in at least one of the branches. Considering the region as a single structure, we find that it is globally close to virial equilibrium indicating that the entire structure is approximately in a stable state.