NAHUAL (Near-infrAred High-resolUtion spectrogrAph for pLanet hunting) will be a
high-resolution (R ~ 60,000) near-infrared echelle spectrograph.
NAHUAL is intended as a trailblazer instrument for 10 m-class telescopes to
provide unique capabilities to perform high-resolution near-infrared
spectroscopy with the goal of detecting Earth-like planets around cool and brown
The science that will be enabled by NAHUAL includes:
- Radial velocity searches for planets around cool stars;
- Dynamical studies of protoplanetary disks;
- Dynamical studies of pre-planetary nebulae stars;
- Chemical composition of solar-system bodies;
- Magnetic fields in red objects;
- Astrosismology of red stars;
- Studies of high redshift gamma-ray bursts.
The main science mode must be optimized for exoplanet research. It will provide
high spectral resolution (R > 60,000), wide spectral coverage and high stability
so that it enables high accuracy RV measurements and
accurate monitoring of line profiles. The challenge is to obtain an accuracy of
1 m/s, which is now routinely achieved with several ground-based echelle
spectrographs in the optical wavelength range (Hamilton at Lick, HARPS at ESO,
HIRES at Keck). In addition to the main mode, NAHUAL may have other modes of
operation that enhance its capabilities for being used by a wide scientific
community. Those modes will be implemented only if they do not compromise the
performance of the main mode. We will call them optional modes.
NAHUAL main science mode will be optimized to observe bright point
sources (J < 12 mag). No image rotator is needed for this operation
because the sources will be much brighter than the sky.
The observations should be matched to the average natural seeing. The main mode
should work without an adaptive optics (AO) facility because of possible PSF
variations, significant light losses and limited sky visibility of AO systems.