Studying the kinematics of the giant star-forming region 30 Doradus ^⋆

I. The data

¹ Departamento de FísicaUniversidad de La Serena, Av. Cisternas 1200 Norte, La Serena, Chile
e-mail: storres@dfuls.cl
² Instituto de Ciencias Astronómicas, de la Tierra y del Espacio, Casilla 467, 5400 San Juan, Argentina
³ Instituto de Astrofísica de Andalucía-CSIC, Glorieta de la Astronomía s/n, 18008 Granada, Spain
⁴ Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile
⁵ Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de la La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina
⁶ Institute for Astronomy, Royal Observatory Edinburgh, Blackford Hill, Edinburgh, EH9 3HJ, UK
⁷ UK Astronomy Technology Centre, Royal Observatory Edinburgh, Blackford Hill, Edinburgh, EH9 3HJ, UK

Received: 1 October 2012
Accepted: 30 April 2013

Abstract

We present high-quality VLT-FLAMES optical spectroscopy of the nebular gas in the giant star-forming region 30 Doradus. In this paper, the first of a series, we introduce our observations and discuss the main kinematic features of 30 Dor, as revealed by the spectroscopy of the ionized gas in the region. The primary data set consists of regular grid of nebular observations, which we used to produce a spectroscopic datacube of 30 Dor, centered on the massive star cluster R136 and covering a field-of-view of 10′ × 10′. The main emission lines present in the datacube are from Hα and [Nii] λλ6548, 6584. The Hα emission-line profile varies across the region from simple single-peaked emission to complex, multiple-component profiles, suggesting that different physical mechanisms are acting on the excited gas. To analyse the gas kinematics we fit Gaussian profiles to the observed Hα features. Unexpectedly, the narrowest Hα profile in our sample lies close to the supernova remnant 30 Dor B. We present maps of the velocity field and velocity dispersion across 30 Dor, finding five previously unclassified expanding structures. These maps highlight the kinematic richness of 30 Dor (e.g. supersonic motions), which will be analysed in future papers.