Is There an Analogue of the Radcliffe Wave between the Carina-Sagittarius and the Scutum Arms?

Abstract

The most complete sample of galactic maser sources and radio stars with trigonometric parallaxes, proper motions and radial velocities measured by the VLBI method has been compiled based on literature data. These sources are associated with young stars located in high mass star forming regions. The rotation parameters of the Galaxy have been determined based on 156 masers with relative parallax errors less than 10\(\%\), located further than 3 kpc from the galactic center. The linear rotation velocity of the Galaxy at the solar distance \(R_{0}\) is \(V_{0}=243.9\pm 3.9\) km s\({}^{-1}\). A very narrow chain of masers \(3{-}4\) kpc long, elongated in the \(l\sim 40^{\circ}\) direction, passing from a segment of the Carina-Sagittarius spiral arm to the Scutum arm, has been studied. A number of authors have hypothesized that this is a possible analogue of the Radcliffe wave. In the present work, no noticeable periodic perturbations of vertical coordinates and velocities were found in this structure. On the other hand, on the diagram ‘‘\(\ln(R/R_{0}){-}\theta\)’’ this chain of masers has the form of a segment of a logarithmic spiral with a pitch angle of \(-48^{\circ}\). Perhaps this chain of masers belongs to a jet extending from the end of the bar, rotating rigidly with the angular velocity of the bar.