Tamura, M.; Suto, H.; Nishikawa, J.; Kotani, T.;
Sato, B.; Aoki, W.; Usuda, T.; Kurokawa, T.; Kashiwagi, K.; Nishiyama,
S.; Ikeda, Y.
; et al.
IRD is the near-infrared high-precision radial velocity instrument for
the Subaru 8.2-m telescope. It is a relatively compact (~1m size)
spectrometer with a new echelle-grating and Volume-Phase Holographic
gratings covering 1-2 micron wavelengths combined with an original
frequency comb using optical pulse synthesizer. The spectrometer will
employ a 4096x4096-pixel HgCdTe array under testing at IfA, University
of Hawaii. Both the telescope/Adaptive Optics and comb beams are fed
to the spectrometer via optical fibers, while the instrument is placed
at the Nasmyth platform of the Subaru telescope. Expected accuracy of
the Doppler-shifted velocity measurements is about 1 m s-1. Helped
with the large collecting area and high image quality of the Subaru
telescope, IRD can conduct systematic radial velocity surveys of
nearby middle-to-late M stars aiming for down to one Earth-mass
planet. Systematic observational and theoretical studies of M stars
and their planets for the IRD science are also ongoing. We will report
the design and preliminary development progresses of the whole and
each component of IRD.