Halpha datacubes of the Carina arm tangency

The spiral arm tangent regions are therefore the best directions for studying the interstellar medium within spiral density waves in the Milky Way, probing the internal structure in the arms. We focus here on the gas kinematics and star formation in the Galactic plane zone with longitudes of between 281{deg} and 285.5{deg} and latitudes of between ~-2.5{deg} and ~1{deg}, respectively, which contains the Carina arm tangency.

The Carina arm tangent direction was observed as part of a velocity-resolved H{alpha} survey of the southern Milky Way using a scanning Fabry-Perot mounted on a telescope, which makes it possible to obtain data cubes containing kinematic information. Our detailed analysis of the resultant H{alpha} profiles reveals the presence of several layers of ionized gas with different velocities over the surveyed region. We combine the H{alpha} data with multi-wavelength information in order to assign velocity and distance to the HII regions in the probed area and to study the star-formation activity in the Carina arm tangency.