Sunrise III

SOLANKI, S.K.; IGLESIAS, FRANCISCO A.; SUNRISE III TEAM

Angkor Wat

Conferencia; Dynamic Sun; 2018

The University of Sheffield et. al.

Sunrise is a balloon-borne solar observatory dedicated to the investigation of the physics of the magnetic field and its interaction with convective plasma flows and waves. The Sunrise observatory is designed for operation in the stratosphere (at heights up to 40 km) in order to avoid the image degradation due to turbulence in the Earth?s lower atmosphere and to gain access to the UV spectral range. The first science flights of Sunrise, in June 2009 and June 2013, led to many new results described in around 90 papers in refereed journals. This includes the first time that magnetic features were fully resolved in the quiet Sun, the first time that the life history of individual magnetic features could be followed, the discovery of a canopy of ubiquitous fibrils in in the lower chromosphere that carries a variety of waves, discovery of a new method by which coronal loops are heated, etc. This success has shown the huge potential of the Sunrise approach. The recovery of the largely intact payload offers an opportunity for a third flight. Sunrise III will have greatly extended capabilities, in particular to measure weaker mag-netic field over a greater range of heights (covering both photosphere and chromosphere). To this end, Sunrise III will carry two new instruments as well as upgrades of its present instruments. One of the new instruments is a novel UV spectropolarimeter that will explore and exploit the rich spectral range between 300 and 430 nm, which is poorly accessible from the ground. In addition, a near-infrared spectropolarimeter will sensitively sample both, the photosphere and chromosphere. The existing imaging magnetograph, IMaX, will be upgraded to greatly increase its speed and to allow it to access multiple spectral lines (compared with a single one so far).These instruments will allow new regimes of the solar magnetic field to be explored.This includes the field in the poorly understood chromosphere, which is the key interaction region between magnetic field, waves, and radiation and plays a central role in transporting energy to the upper solar atmosphere. In addition, the presence of many spectral lines sensitive to the Hanle effect in the spectral regions covered by the new Sunrise instruments will allow Sunrise III to be sensitive to weak magnetic fields as found in the quiet Sun and in the chromosphere.