SLAC National Accelerator Laboratory received an additional $21.8 million in the final round of funding for national laboratories through the federal economic stimulus package.

The money will go toward construction and improvements at the laboratory's research facilities on light sources, according to a SLAC representative. All told, SLAC has received $90 million of the $220 million awarded to national laboratories through the stimulus package.

Of the $21.8 million, $20 million will fund the construction of an instrument to study transient states of matter that "can exist during fusion processes, the evolution of stars, and inside supernovae," SLAC said in a statement.

The remaining $1.8 million will go toward upgrades and the purchase of new equipment in another SLAC light source research facility.

Previous stimulus funding for SLAC went toward speeding the assembly of a new X-ray device, supporting the subatomic particle accelerator, and seismic upgrades to the structures.

SLAC is located on Sand Hill Road and is operated by Stanford University for the federal energy department's Office of Science.