Uniformity and Stability of the LSST Focal Plane

Understand

The LSST focal plane consists of 21 autonomous modules ("Raft Tower Modules", RTM), each of which contains nine thick, fully-depleted 4K x 4K CCDs with associated control and readout electronics.

• To enable LSST's repetitive short-exposure cadence while maintaining high duty factor and low read noise, the readout is highly parallelized into 3024 independent video channels (16 per CCD, 144 per RTM).
• Two vendors supplied the LSST sensors; the devices have compatible mechanical and electrical interfaces and meet the same electro-optic specifications, but each RTM is constructed with sensors from a single supplier.
• The full complement of rafts were assembled at Brookhaven National Laboratory during January 2017 - March 2019.