Gray (unit) Gray (unit) The gray (symbol: Gy) is a derived unit of ionizing radiation dose in the International System of Units (SI). It is defined as the absorption of one joule of radiation energy per kilogram of matter. It is used as a unit of the radiation quantity absorbed dose which measures the energy deposited in a unit mass at a certain position, and of the radiation quantity kerma, which is the amount of energy that is transferred from photons to electrons per unit mass at a certain position. The corresponding cgs unit to the gray is the rad (equivalent to
National Energy Research Scientific Computing Center the machines in Oakland were taken down and moved. View the interactive timeline created in 2014 in recognition of NERSC's 40 years of HPC leadership. View the list of computer systems installed at NERSC since 1996. To reflect NERSC's mission to support scientific research, the center names its major systems after scientists. The center is located in Shyh Wang Hall, one of the nation's most energy-efficient supercomputer facilities. The building was financed by the University of California which manages Berkeley Lab for the U.S. Department of Energy (DOE). The utility infrastructure and computer systems are provided by DOE. The newest