We have undertaken the largest survey for outflows within the Galactic plane using simultaneously observed 13 CO and C 18 O data. Out of a total of 919 ATLASGAL clumps, 325 have data suitable to identify outflows, and 225 (69 ± 3%) show high-velocity outflows. The clumps with detected outflows show significantly higher clump masses (M clump ), bolometric luminosities (L bol ), luminosity-to-mass ratios (L bol /M clump ), and peak H 2 column densities (N H 2 ) compared to those without outflows. Outflow activity has been detected within the youngest quiescent clump (i.e., 70µm weak) in this sample, and we find that the outflow detection rate increases with M clump , L bol , L bol /M clump , and N H 2 , approaching 90% in some cases (UC Hii regions = 93%±3%; masers = 86%±4%; HC Hii regions = 100%). This high detection rate suggests that outflows are ubiquitous phenomena of MSF (MSF). The mean outflow mass entrainment rate implies a mean accretion rate of ∼ 10 −4 M yr −1 , in full agreement with the accretion rate predicted by theoretical models of MSF. Outflow properties are tightly correlated with M clump , L bol and L bol /M clump , and show the strongest relation with the bolometric clump luminosity. This suggests that outflows might be driven by the most massive and luminous source within the clump. The correlations are similar for both low-mass and high-mass outflows over 7 orders of magnitude, indicating that they may share a similar outflow mechanism. Outflow energy is comparable to the turbulent energy within the clump; however, we find no evidence that outflows increase the level of clump turbulence as the clumps evolve. This implies that the origin of turbulence within clumps is fixed before the onset of star formation.

Aims. Surveys of the Milky Way at various wavelengths have changed our view of star formation in our Galaxy considerably in recent years. In this paper we give an overview of the GLOSTAR survey, a new survey covering large parts (145 square degrees) of the northern Galactic plane using the Karl G. Jansky Very Large Array (JVLA) in the frequency range 4 − 8 GHz and the Effelsberg 100m telescope. This provides for the first time a radio survey covering all angular scales down to 1.5 arcsecond, similar to complementary near-IR and mid-IR galactic plane surveys. We outline the main goals of the survey and give a detailed description of the observations and the data reduction strategy. Methods. In our observations we covered the radio continuum in full polarization, as well as the 6.7 GHz methanol maser line, the 4.8 GHz formaldehyde line, and seven radio recombination lines. The observations were conducted in the most compact D configuration of the VLA and in the more extended B configuration. This yielded spatial resolutions of 18" and 1.5" for the two configurations, respectively. We also combined the D configuration images with the Effelsberg 100-m data to provide zero spacing information, and we jointly imaged the D-and B-configuration data for optimal sensitivity of the intermediate spatial ranges. Results. Here we show selected results for the first part of the survey, covering the range of 28 • < l < 36 • and |b| < 1 • , including the full low-resolution continuum image, examples of high-resolution images of selected sources, and the first results from the spectral line data.