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Maser emission plays an important role as a tool in star formation studies. It is widely used for deriving kinematics, as well as the physical conditions of different structures, hidden in the dense environment very close to the young stars, for exam ple associated with the onset of jets and outflows. We will summarize the recent observational and theoretical progress on this topic since the last maser symposium: the IAU Symposium 242 in Alice Springs.
In recent studies of methanol masers, a substantial fraction of the objects show maser components aligned in large-scale elliptical configurations. These can be readily interpreted as rings centred on a high mass star in formation, seen in projection . Remarkably, most of these rings do not show signs of rotation, but rather the radial motions dominate. This must mean that their dynamics are governed by other than gravitational forces. In particular, we have studied the methanol masers around Cep A in detail, where it can be argued that the methanol masers show signs of infall. In this paper we discuss the dynamics of the Cep A methanol maser and sources from the Torun blind survey to argue that at least in a fraction of sources methanol masers could be associated with the shock interface between the large scale accretion, regulated by the magnetic field, and a 1000-AU scale circumstellar disk. We discuss the validity of such a model for the overall population of methanol maser sources.
Guided by the recently published science case for the future of European VLBI, EVN2015, a roadmap for the future of the EVN is sketched out in this paper. The various desired technical improvements are being discussed with an emphasis on the role of e-VLBI. With this innovation new scientific capabilities are introduced. In this way the EVN is also positioned as an interesting platform for exercising new techniques and operational models, complementary to other SKA pathfinders. In return, the technology development for the SKA can have a positive impact on the scientific capabilities of VLBI, for example on the development of a next generation correlator, capable to process much larger data-rates. The development of cheap, frequency agile antennas can also be of great importance for VLBI. This adds to the potential for maintaining a Northern hemisphere, global VLBI array in the SKA era.
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