KODIAQ Dataset

This document describes the KODIAQ dataset.

Sources

The Keck Observatory Database of Ionized Absorption toward Quasars (KODIAQ) survey is a public spectra data release of quasars observed with the HIRES spectrometer on the Keck I telescope. The first Data Release (DR1) became available in 2015, as described in O’Meara et al. (2015).

The second data release is now available in igmspec v03 and the paper describing its contents is: O’Meara et al. (2017).

Meta Data

The additional meta data provided with KODIAQ follows from Table 1 of O’Meara et al. (2015). These are:

Key	Type	Description
pi_date	str	PI and Observation Date
spec_prefix	str	Spectrum prefix
redux_setup	str	Reduction setup
targname	str	Target name set by observer
deckname	str	Name of the HIRES decker used
elaptime	str	Description of the total exposure time (seconds)
qaflag	str	Description of the data reduction process
kodetime	int	Total exposure time of the co-added spectrum (seconds)
kodwblue	int	Approximate starting wavelength (Ang)
kodwred	int	Approximate ending wavelength (Ang)
kodrelease	int	KODIAQ data release (1=DR1, 2=DR2)

Spectra

In igmspec v03 are all of the spectra released in DR1 and DR2 of KODIAQ in separate data groups: KODIAQ_DR1, KODIAQ_DR2. These data are continuum normalized.

Redshifts

The redshifts provide in DR1 were drawn from Simbad. In DR2, preference is given to the SDSS with Simbad as the secondary source.