Saul Perlmutter
Professor of Physics, UC Berkeley
Senior Scientist, LBNL



Current Projects

The Supernova Cosmology Project

The SCP is conducting a search for very distant (redshifts greater than 1.2) Type Ia supernovae using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. We are searching on the same area of sky covered by the GOODS-N survey (Giavalisco et al. 2003), which is roughly centered on the Hubble Deep Field North (Williams et al. 1996). Observations are divided into four search epochs separated by approximately 50 days.Each of the four searches is comprised of 15 ACS pointings which cover a total of 170 square arcminutes. Variable objects, such as high redshift supernovae, are identified by subtracting the 2003 GOODS-N ACS imaging from the new search images. For the second, third, and fourth searches,the previous search epochs provide additional information useful for determining which supernovae were discovered before maximum light, making them suitable candidates for the subsequent follow-up. Supernovae will be reported via IAU Circulars and on web page ( This search is done in coordination with the STScI Higher-z Team, with both teams searching independently, comparing results, and then following different supernovae.

SNAP (SuperNova/Acceleration Probe) Satellite Project

The discovery by the Supernova Cosmology Project (SCP) and the High-Z Supernova team that the expansion of the universe is accelerating poses an exciting mystery — for if the universe were governed by gravitational attraction, its rate of expansion would be slowing. Acceleration requires a strange “dark energy’ opposing this gravity. Is this Einstein’s cosmological constant, or more exotic new physics? Whatever the explanation, it will lead to new discoveries in astrophysics, particle physics, and gravitation. More information online at

Nearby Supernova Factory

The Nearby Supernova Factory (SNfactory) is an experiment to develop Type Ia supernovae as tools to measure the expansion history of the Universe and explore the nature of Dark Energy. It is expected to be the largest supernova program yet performed.

The SNfactory is an international collaboration between several groups in the United States and France, including Lawrence Berkeley Lab and IN2P3/CNRS in France. The experiment is designed to address a wide range of supernova issues using detailed observations of low-redshift SN.





Research Publications