Test observation results from the mid-infrared imager MIRTOS for the Subaru Telescope

MIRTOS, Mid-Infrared Test Observation System, is a high spatial resolution mid infrared (MIR) camera for the Subaru Telescope. It consists of two infrared imagers. One is for MIR bands with a Si:As array with 320x240 pixels. It has 21x16 arcsec field of view (FOV) with a pixel scale of 0.067 arcsec. It also images the pupil of the telescope. The other is a near infrared (NIR) camera. A 256x256 InSb array with 0.028 arcsec/pixel is used to image 7x7 arcsec FOV at one corner of the MIR FOV. We apply Shift-and-Add (SAA) technique; a technique that shifts images detecting the displacements and adds them to cancel seeing. However it is often difficult to shift and add MIR images using a reference within because of low sensitivity in MIR for short exposure time. We solve this problem utilizing NIR images taken simultaneously as position references. We call this method Two-Wavelength Shift-and-Add (TWSAA). In this paper we show results from the test observations. 1) Pupil image was taken. It shows hot structures around the secondary mirror that are now planned to be covered by reflecting plates to direct the beam to the sky. 2) Correlation of motion between MIR peak position and NIR centroid position shows that NIR images can be used as TWSAA reference for MIR observations. 3) On a, standard star and the core NGC 1068, SAA method was applied to reconstruct images. Resulting images how higher spatial resolution than previous observations.