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Last update: 23 April 2014 (January 2016)
Research and Development Facility
Town or city
Upton, New York
40°51′55.38″N 72°52′19.71″W / 40.8653833°N 72.8721417°W / 40.8653833; -72.8721417
United States Department of Energy
400,000 sq ft (37,000 m2) 
Design and construction
Torcon, Inc. 
BNL: National Synchrotron Light Source II (NSLS-II)
Exterior of National Synchrotron Light Source II facility, taken 22 July 2012 during Brookhaven National Laboratory “Summer Sundays” public tour.
National Synchrotron Light Source II, or NSLS-II, is being constructed at Brookhaven National Laboratory in New York. It will cost US$912,000,000. NSLS-II will replace the original National Synchrotron Light Source (NSLS). Construction of NSLS-II began in 2009 and operations are expected in 2015. NSLS-II will be a new state-of-the-art, medium-energy electron storage ring operating at 3 GeV. It is designed to produce x-rays more than 10,000 times brighter than the original NSLS.
The NSLS-II storage ring is 792 m in length and there will be 60 to 80 beamlines. NSLS-II is designed to deliver photons with high average spectral brightness in the 2 keV to 10 keV energy range exceeding 1021 ph/s/0.1%BW/mm2/mrad2. The spectral flux density should exceed 1015 ph/s/0.1%BW in all spectral ranges. This is considered cutting-edge performance and requires the storage ring to support a very high-current electron beam of 500 mA. The ring will operate at 3 GeV, which is considered medium range; its high brightness and flux will make NSLS-II unique.
^ a b “NSLS-II Project Data Sheet is for PED/Construction” (PDF). Dept. of Energy. Retrieved 4 August 2010.
^ “First Concrete Poured for NSLS-II Ring Building”. bnl.gov. Retrieved 28 March 2011.
^ “NSLS-II Contract Will Mean Hundreds of Jobs for Long Island”. bnl.gov. Retrieved 28 March 2011.
^ a b “About the NSLS-II Project”. BNL.gov. Retrieved 4 August 2010.
^ a b c “NSLS-II Source Properties and Floor Layout” (PDF). BNL.gov. Retrieved 4 Augus