Diagnostic Capability of the Sunrise Chromospheric Infrared spectroPolarimeter (SCIP) for SUNRISE-3

The SUNRISE balloon-borne solar observatory carries a 1 m aperture optical telescope, and provides us a unique platform to conduct seeing-free continuous observations at UV-visible-IR wavelengths in the stratosphere. For the next flight in 2021, the post-focus instrumentation was upgraded with completely new spectro-polarimeters for the near UV (SUSI) and the near-IR (SCIP), while the imaging spectro-polarimeter IMaX+ is capable of observing not only the photosphere, but also the chromosphere. This new suite will allow for detailed measurements of the atmospheric parameters from the photosphere up to the chromosphere at a spatial resolution of 70 to 150 km.

The international team led by NAOJ is developing the near IR spectro-polarimeter SCIP which observes the two wavelength ranges in near-IR around 770 nm and 850 nm simultaneously. By combining multiple Zeeman-sensitive lines, such as Fe I 846.8 nm, K I 766.5 and 769.9 nm, and Ca II 849.8 and 854.2 nm, we are able to obtain magnetic and velocity structures with enough height resolution from the photosphere to the chromosphere, which is essential to understand how the energy is transferred and dissipated in the atmosphere. Performance of SCIP is demonstrated by reproducing spectral line profiles using MHD numerical simulations together with non-LTE radiative transfer calculation. We will present some examples on how SCIP can detect signatures of dynamical phenomena responsible for atmospheric heating, such as jets, MHD waves, and magnetic reconnection.