Astrophysics and Cosmology

Simulation image of a dwarf galaxy

SLAC astrophysicists and cosmologists play leading roles in the study of the high-energy universe, where cosmology and particle physics – the study of the very big and the very small – meet. In this approach to discovery, known as the cosmic frontier, the universe itself is their laboratory. Two of the biggest puzzles in this realm are the nature of the dark matter and dark energy that make up 95 percent of the universe.

SLAC managed construction and assembly of the main instrument for the Fermi Gamma-ray Space Telescope, an international project launched by NASA in 2008 to observe the universe in gamma rays. These high-energy rays bring us invaluable information about the extreme events that caused them, such as black holes and exploding stars. They may also yield evidence for dark matter, which so far has only been seen through its gravitational influence on the growth of structures in the universe.

SLAC is leading the design and construction effort for the 3.2 gigapixel camera – the world’s biggest – planned for the Large Synoptic Survey Telescope. The LSST will photograph the entire southern sky every 3.5 days, providing a unique view of the transient universe. This will allow scientists to track the evolution of the universe and any changes in its expansion rate over time, giving us great insight into the nature of dark energy.

The laboratory is also playing a key role in the Super Cryogenic Dark Matter Search experiment, a next-generation search for dark matter that will take place deep underground at Canada’s SNOLAB. SLAC is developing the experiment’s germanium-crystal detectors. Chilled to extremely cold temperatures and shielded under 6,800 feet of rock, they will attempt to record signals from dark matter WIMPs – weakly interacting massive particles – which, as the name implies, usually pass through normal matter without leaving a trace.

At the Kavli Institute for Particle Astrophysics and Cosmology, researchers from SLAC and Stanford bring the resources of modern computational, experimental, observational and theoretical science to bear on our understanding of the universe.

One result: the mysteries of the universe – from the first stars to galaxy clusters and dark matter – are revealed in stunningly beautiful full-color, high-definition 3-D visualizations made by scientists at KIPAC’s Visualization Lab. These visualizations help scientists understand their data, and also find their way into planetarium shows that inspire and educate the public.