Data Management Tasks at UW

The topics below outline the main tasks assigned to the LSST DM team at UW. The team currently comprises Andrew Becker, Andy Connolly, Simon Krughoff, Russell Owen, and Nicole Silvestri. More information about the software and the development can be found on the LSST Trac pages.

Instrument Signature Removal

The Data Management group at UW is responsible for writing the code to remove the instrument signature from data coming from the camera. Since the camera is physically large (about 0.5x0.5 m) and has a very large field of view (10 square degrees) and made up almost 200 individual chips, the signature imprinted by the optics and electronics can vary significantly over a single huge (3 gigapixel) image. All the individual chips must be corrected for several instrumental effects. Some examples are:

Difference Imaging

Andy B. add info here...

PSF Determination

Andy B. add info here...

Template Co-Addition

LSST will use coadded template images for several purposes, including image subtraction and detecting faint objects for use by deep detection. We are examining various methods of coadding images including match filtering (convolving each input image by its PSF to filter out noise).

Convolution

The LSST software stack supports convolution of images and masked images with kernels of various types. Most of these can be spatially varying. For more information see the doxygen-generated documentation for afw, in particular the convolve function and the Kernel class.

The Software Stack at UW

The LSST software data processing software stack is available in /astro/apps/lsst64 as described here: LSST Data Processing Software on the UW Astronomy wiki. That page has links to documentation and a source code browser.