ANIR infrared first light at Higashi-Hiroshima Astronomical Observatory in January 2009

A near-infrared camera ANIR successfully saw the first light in the infrared at the Kanata Telescope of the Higashi-Hiroshima Astronomical Observatory. These observations confirmed that all of ANIR's functions work as designed, and that ANIR is now ready to be transported to Chile for scientific observations.

# Participants: Motohara, Mitani, Sako, Toshikawa, and Ohsawa
# Date: from January 23 to January 27, 2009

Fig. 1: ANIR installed on the 1.5-m Kanata Telescope of Higashi-Hiroshima Observatory with the development team members

1. ANIR performance test observations

This time, the observation was made with an engineering-grade infrared detector, which arrived in December 2008. Four broad-band filters and three narrow-band filters were newly installed in a filter exchange mechanism. In addition, a new simultaneous visible imaging unit utilizing a dichroic mirror was also installed.

• Infrared observation performance
  • A good image quality with a half-width of 0.9 arcsec was obtained, which is one of the sharpest image quality obtained at the Kanata Telescope, and confirmed that there were no problems with imaging performance.
  • Imaging observations with all the filters confirmed that there were no problems with filter performance and that the camera throughput was almost as designed.
  • The readout noise on the telescope was found to be about 20e- r.m.s., which fulfilled the requirement.
• Visible Simultaneous Imaging Test
  • The simultaneous visible imaging unit was confirmed to achieve the designed imaging performance and throughput together with the dichroic mirror.
• Automated Observation Test
  • Automated observations by ANIR fore more than one hour, communicating with the telescope were successfully carried out. They include simultaneous infrared and visible imaging observations.

Fig. 2: ANIR installed on the Cassegrain focus of the 1.5-m Kanata Telescope at Higashi-Hiroshima observatory.

2. Images taken with ANIR

Followings are the infrared first light images of ANIR obtained during the observations.

Fig. 3: Orion Trapezium (Pa-beta H, Ks tricolor composite)

Fig. 4: Gemini Eskimo Nebula NGC2392 (Y, Pa-beta J tricolor composite)

3. Upcoming events

Through the observations, we confirmed that the performance of ANIR had met its initial goals and that it was ready to be transported to Atacama for observations at the summit of Co. Chajnantor. ANIR was then returned to Mitaka, and after minor maintenance and upgrades, and it was shipped to Atacama, Chile at the end of March 2009. First light observations at Co. Chajnantor are scheduled in June 2009.