README

Each Keck/HIRES spectrum consists of three individual files. Each file is 
prefixed with an letter indicating the HIRES chip. Each chip covers the 
following range of wavelengths:

'i' (6540-8000 Ang)
'r' (4975-6420 Ang)
'b' (3640-4800 Ang)
The CPS spectral analysis uses only the central ('r') spectrum.

Within each .fits file, there are three extensions of equal dimemsions:

The first extension is the spectrum itself, in echelle format. 
The values are flux, in arbitray units. 
The blaze function has been removed from each spectral order.

The second extension gives the fractional error per pixel.

The third extension holds the rest frame wavelength solution, which is accurate
 to ~1 HIRES pixel or ~1.2 km/s or ~0.02 angstroms.

The CKS spectra are defined with respect to the rest frame of HIRES. 
For precision spectroscopy, it is more convenient to register (shift) spectra 
onto the rest frame of the star, i.e. H-alpha at 6563 angstroms. The open source
code Empirical-SpecMatch, developed by Yee, Petigura, and von Braun (2017) 
contains a module to facilitate the registration of HIRES spectra. For example,
shifting registering KOI-7 (systemic RV = −60.8 km/s).

For more details, and referneces checkout these online references:
https://github.com/California-Planet-Search/cks-website



TABLE DATA:
K2_key_project_stellar_properties_compilation.csv

Columns and definitions:
star                Starname
ra                  Right_Ascension (Hours)
dec                 Declinatin (Degrees)
teff_syn            Effective Temperature Synethic (K)
teff_err_syn        Effective Temperature Synethic Error (K)
fe_syn              Metallicity Synthetic
fe_err_syn          Metallicity Synthetic error
logg_syn            Stellar Surface gravity Synthetic
logg_err_syn        Stellar Surface gravity Synthetic error
mass_syn            Stellar Mass Synthetic (M_sun)
mass_err_syn        Stellar Mass Synthetic error (M_sun)
radius_syn          Stellar Radius Sythetic (R_sun)
radius_err_syn      Stellar Radius Sythetic error (R_sun)
vsini_syn           Stellar Rotation Velocity (km/s)
vsini_err_syn       Stellar Rotation Velocity error (km/s)
teff_emp            Empirically Derived Stellar Temperature (K)
teff_err_emp        Empirically Derived Stellar Temperature error (K)
fe_emp              Empirical Metallicity
fe_err_emp          Empirical Metallicity err
radius_emp          Empirical Stellar Radius (R_sun)
radius_err_emp      Empirical Stellar Radius err (R_sun)

SpecMatch-Empirical Reference:
https://iopscience.iop.org/article/10.3847/1538-4357/836/1/77/pdf

Software Available on Github:
https://specmatch-emp.readthedocs.io/en/latest/index.html

SpecMatch-Syntheitc Reference:
https://iopscience.iop.org/article/10.3847/1538-3881/aa80de/pdf