Presenting a World-Class Spectral Library with Comprehensive Near-IR Coverage at High Resolution

Spectral libraries are a key resource in many astrophysical studies. High spectral resolution is particularly valuable where the intrinsic line shapes of photospheric absorption lines present in spectra of late type stars are fully resolved. Thus, the observed spectra of standard stars with accurately known physical properties allows a direct comparison with detailed modeled spectra to calibrate their theoretical input parameters. Using the near-IR spectrograph, NIRSPEC, at Keck Observatory we have constructed a library of standard stellar spectra at high resolution (R~50,000) with wavelength coverage spanning the entire near-IR region (i.e. yJHKL bands, 0.95 – 3.5 microns). To achieve this continuous wavelength coverage with NIRSPEC, we observed each target at 9 separate echelle + cross disperser grating configurations delivering 59 echelle orders. The library sample is comprised of exoplanet host stars (Yee et al. 2017), having accurately measured or calculated fundamental properties (i.e., Teff, log g, [Fe/H], mass, radius and age) characterized from optical spectra taken at high resolution (R∼60,000) with high signal-to-noise (SNR/pix > 140) using the HIRES spectrograph at Keck Observatory. We have chosen ~45 stars from the optical study, that span a range in spectral type (i.e., F, G, K, & M), luminosity class (i.e., dwarfs, sub-giants, and giants), and metallicity (i.e., ±0.3 [Fe/H]). The library site is accessible via the NIRSPEC Instrument webpage at: https://www2.keck.hawaii.edu/inst/nirspec/Speclib/index.html. We anticipate this spectral library will be a valuable resource for the community, providing the first high resolution and comprehensive near-IR coverage to date.