Infrastructure for solar physics: the European Solar Telescope (EST)

The European Solar Telescope (EST) is a proposed 4.2-m diameter telescope with planned start of operations in 2029.

It will replace the European national solar telescopes currently in operation, including the Swedish 1-m Solar Telescope (SST). EST will consolidate the European community around a single outstanding research facility for the next 40-years.

EST will have high photon throughput and polarimetric accuracy because of its symmetric design and its innovative adaptive secondary mirror.

It will be equipped with a sophisticated instrument suite including Fabry-Pérot interferometers and integral-field spectrographs, that are designed to work in tandem and can determine the 3D magnetic field structure in the solar photosphere and chromosphere at spatial scales of order 10 km and a time scale of seconds.This proposal asks for a VR contribution to EST construction costs of 91 MSEK.

Together with 9 MSEK co-financing from SU, this is 5% of the total cost of EST. 65 MSEK shall be payed into the EST ERIC, while 35 MSEK shall be spent in Sweden as a direct in-kind contribution.The Institute for Solar Physics (ISP) at Stockholm University has a long and unique experience of operating a solar telescope with Fabry-Perot interferometers and integral-field spectrographs of the type to be installed at EST.

The in-kind contribution shall therefore be the development of the data reduction pipeline for the EST instruments.The proposed funding will allow the ISP and Sweden to continue to keep their world-leading positions in solar research and support EST as a pan-European project.