SAFARI : a far-infrared imaging spectrometer for SPICA

How was the universe born and how has it evolved ? How were the Earth and habitable living beings like us created ? To answer these questions is the ultimate objective of astronomy. SPICA, a large-aperture (2.5 m) cryogenic space telescope, will tackle these questions through infrared studies of galaxy evolution and planet formation.

The SAFARI is a diffraction grating spectrometer designed to achieve the highest-ever sensitivity for line emission in the wide far-infrared wavelength range of λ = 34 - 210 μm (TBD) with a moderate wavelength resolution (R=300). The SAFARI will employ a TES (Transition Edge Sensor) bolometer as a far-infrared detector. An additional function enabling high-resolution observations (R=3,000) by a combination of a Fabry‐Perot interferometer with the diffraction grating is under consideration. With its beam steering mirror, it can perform imaging observations of a 2 arc minute square region on the sky. This function is effective to observe diffuse celestial objects. The SAFARI Consortium consisting of institutes/universities from Europe, Canada and U.S.A is responsible for development of the SAFARI.

In the SAFARI wavelength range, there are various bright emission lines from ionized gas. With its high sensitivity, the SAFARI can reveal star formation history in galaxies and evolution of supermassive black holes at their center, by detecting these emission lines from distant galaxies.