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We have developed the Wide Field Grism Spectrograph 2 (WFGS2) for the f/10 focus of the University of Hawaii 2.2 m telescope (UH88). This instrument provides slit-less, wide-field spectroscopy as well as imaging and long-slit spectroscopy. Two CCD cameras of UH88, Tektronix 2k × 2k and OPTIC 4k × 4k, can be used as a detector. The spectral coverage is 380 - 970 nm, and the field of viewis 11’.5 × 11’.5 with a pixel scale of 0”.34 (Tektronix) or 0”.21 pixel −1 (OPTIC) in the imaging mode. WFGS2 has two replica grisms (R = 620 at 650 nm and R = 730 at 400 nm) and a Volume-Phase Holographic (VPH) grism (R = 2500 at 664 nm). The VPH grism enables intermediate-dispersion spectroscopy with this transmission system. Two long-slits with widths of 0”.6 and 0”.9 can be used. The Sloan Digital Sky Survey (g � ,r � ,i � ,z � ) and narrow-band (wide Hα ,H α, and [SII]+Li) filters are equipped. The first light observation was done in November 2003. We present the details of WFGS2, including the results of the first light observation.

We developed a near infrared simultaneous three-band (J, H and Ks) camera, SIRIUS. The design of SIRIUS is optimized to deep, large area surveys in the three IR bands. SIRIUS is equipped with three 1024 x 1024 HgCdTe (HAWAII) arrays, providing simultaneous three-band images. SIRIUS has obtained its first light on the UH 2.2 m telescope in August 2000. SIRIUS is now mounted on the IRSF 1.4 m telescope in Sutherland and is dedicated to deep survey in the southern sky from November 2000. On this telescope, SIRIUS provides 7'.8 x 7'.8 field of view with a pixel scale of 0".45 in all bands. The typical limiting magnitudes are J = 19.2 mag, H = 18.6 mag, Ks = 17.3 mag (15 min. integration, S/N = 10 σ). The effective exposure time (30 sec exposure for each frame) in an hour is about 37 minutes (60%) for each band. Both the instrument and the 1.4 m telescope are in operation.

Some results from the near infrared camera SIRIUS are presented. SIRIUS is designed for deep and wide JHKs-bands simultaneous surveys, being equipped with three science-grade HAWAII (1024×1024) arrays. SIRIUS is attached on a dedicated 1.4m telescope (IRSF) at Sutherland observatory in South Africa. The field of view is 7.8'×7.8', the pixel scale is 0.45", and the limiting magnitude is J=19.2, H=18.6, Ks=17.3 (S/N=10σ and 15minutes integration) with the 1.4m telescope. The survey of southern sky began in November 2000. SIRIUS was also used on the University of Hawaii 2.2m telescope at Mauna Kea for three times in August 2000, October 2000, and September 2001. Surveys of several northern sky areas were done. Unbiased deep survey for 6 degree square area of Large Magellanic Cloud (LMC) is one of the key programs with the 1.4m telescope. Several clusters of intermediate mass YSO candidates have been discovered so far. Monitoring surveys of several selected areas of LMC have also been carried out for detection of variable stars. The other main science programs of SIRIUS are deep imaging surveys of star forming regions in our galaxy, brown dwarf surveys in clusters, search for galaxies behind the Milky way (the Zone of Avoidance), and surveys toward the galactic center.