About PAC
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Research at the Particle Astrophysics and Cosmology (PAC) Division at SLAC takes place on the Cosmic Frontier. Our scientists search for answers to fundamental questions about the building blocks of matter and the nature of space and time. They carry out experiments on the Earth's surface, underground and in space. They help design and build the instruments used in these quests, including underground detectors, precision silicon tracking systems for colliders, a space telescope and the world’s biggest digital camera. Theorists, experimenters and experts in computer simulation, mechanical engineering and other technical fields all join forces to push these studies ahead.
Cosmic Frontier
At the Cosmic Frontier, scientists use the cosmos as a laboratory for studying how the laws of physics shaped the formation and evolution of the universe. 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 is pursuing these and other questions with telescopes on the ground and in space and a detector deep underground. Many of these efforts involve scientists at the joint SLAC/Stanford Kavli Institute for Particle Astrophysics and Cosmology (KIPAC).
