Optical Alignment Method for the PRIME Telescope

Abstract

We describe the optical alignment method for the Prime-focus Infrared Microlensing Experiment (PRIME) telescope which is a prime-focus near-infrared (NIR) telescope with a wide field of view for the microlensing planet survey toward the Galactic center that is the major task for the PRIME project. There are three steps for the optical alignment: preliminary alignment by a laser tracker, fine alignment by intra- and extra-focal (IFEF) image analysis technique, and complementary and fine alignment by the Hartmann test. We demonstrated that the first two steps work well by the test conducted in the laboratory in Japan. The telescope was installed at the Sutherland Observatory of South African Astronomical Observatory in August, 2022. At the final stage of the installation, we demonstrated that the third method works well and the optical system satisfies the operational requirement.

16 pages, 10 figures, and 6 tables. Accept for publication in Journal of Astronomical Instrumentation

References in corpus (6)

• No large population of unbound or wide-orbit Jupiter-mass planets
• The Exoplanet Mass-Ratio Function from the MOA-II Survey: Discovery of a Break and Likely Peak at a Neptune Mass
• Predictions of the Nancy Grace Roman Space Telescope Galactic Exoplanet Survey II: Free-Floating Planet Detection Rates
• A Parametric Galactic Model toward the Galactic Bulge Based on Gaia and Microlensing Data
• VVV Survey Microlensing: the Galactic Latitude Dependence
• Terrestrial and Neptune mass free-floating planet candidates from the MOA-II 9-year Galactic Bulge survey