This week, the Keck Observatory Archive (KOA) released data from its third instrument, and its first imaging instrument: the Near Infrared Camera 2 (NIRC2). Commissioned in 2001, it is used in imaging and spectroscopic modes, and is equipped with three cameras – wide-field, medium-field, and narrow-field cameras – with different fields of view and pixel scales. NIRC2 has been used in many fields of research, but most recently it has been used to show that some brown dwarf candidates discovered by the Wide-field Infrared Survey Explorer (WISE) mission are indeed Y-dwarfs (see slide below).
The archive currently serves over 1,200 nights of data that are publicly accessible. The science and calibration data and calibrated images together together total over 400,000 files, with a volume of 1.25 TB. As new observations are made, they will be transferred electronically to the archive and made available to investigators in the afternoon following the observations. Investigators have exclusive use of the data for at least 18 months after the date of observation.
Altogether, the archive serves data from HIRES and NIRSPEC echelle spectrographs as well as NIRC2, and contains over 10 TB of data. A simple, web based query supports queries across all three instruments.
The release of the NIRC2 data also sees release of an interactive return page, shown below, developed in cooperation with the NASA Exoplanet Archive. This interactive return page is designed to scale to large data sets: all filtering is done on the server side and sent to the browser for display. The SQLite engine is used to perform complex queries requested by the user. SQLite is a library that embeds a database engine in the executable image: it does not need a separate server.