Sept. 12, 2019
LLNL engineer Vincent Riot (left), who has worked on the Large Synoptic Survey Telescope (LSST) for more than a decade and has been the full camera project manager since 2017, and LLNL optical engineer Justin Wolfe, the LSST camera optics subsystems manager, stand in front of the LSST main lens assembly. Photo by Farrin Abbott/SLAC National Accelerator Laboratory.
When the world’s newest telescope starts imaging the southern sky in 2023, it will take photos using optical assemblies designed by Lawrence Livermore National Laboratory (LLNL) researchers and built by Lab industrial partners.
A key feature of the camera’s optical assemblies for the Large Synoptic Survey Telescope (LSST), under construction in northern Chile, will be its three lenses, one of which at 1.57 meters (5.1 feet) in diameter is believed to be the world’s largest high-performance optical lens ever fabricated.
The lens assembly, which includes the lens dubbed L-1, and its smaller companion lens (L-2), at 1.2 meters in diameter, was built over the past five years by Boulder, Colorado-based Ball Aerospace and its subcontractor, Tucson-based Arizona Optical Systems.
Mounted together in a carbon fiber structure, the two lenses were shipped from Tucson, arriving intact after a 17-hour truck journey at the SLAC National Accelerator Laboratory in Menlo Park.
SLAC is managing the overall design and fabrication, as well as the subcomponent integration and final assembly of LSST’s $168 million, 3,200-megapixel digital camera, which is more than 90 percent complete and due to be finished by early 2021. In addition to SLAC and LLNL, the team building the camera includes an international collaboration of universities and labs, including the Paris-based Centre National de la Recherche Scientifique and Brookhaven National Laboratory.
“The success of the fabrication of this unique optical assembly is a testament to LLNL’s world-leading expertise in large optics, built on decades of experience in the construction of the world’s largest and most powerful laser systems,” said physicist Scot Olivier, who helped manage Livermore’s involvement in the LSST project for more than a decade.
Olivier said without the dedicated and exceptional work of LLNL optical scientists Lynn Seppala and Brian Bauman and LLNL engineers Vincent Riot, Scott Winters and Justin Wolfe, spanning a period of nearly two decades, the LSST camera optics, including the world’s largest lens, would not be the reality they are today.
“Riot’s contributions to LSST also go far beyond the camera optics — as the current overall project manager for the LSST camera, Riot is a principal figure in the successful development of this major scientific instrument that is poised to revolutionize the field of astronomy,” Olivier added.
LSST Director Steven Kahn, a physicist at Stanford University and SLAC, noted that “Livermore has played a very significant technical role in the camera and a historically important role in the telescope design.”
Livermore’s researchers made essential contributions to the optical design of LSST’s lenses and mirrors, the way LSST will survey the sky, how it compensates for atmospheric turbulence and gravity, and more.
LLNL personnel led the procurement and delivery of the camera’s optical assemblies, which include the three lenses (the third lens, at 72 centimeters in diameter, will be delivered to SLAC within a month) and a set of filters covering six wavelength-bands, all in their final mechanical mount.
Livermore focused on the design and then delegated fabrication to industry vendors, although the filters will be placed into the interface mounts at the Lab before being shipped to SLAC for final integration into the camera.
The 8.4-meter LSST will take digital images of the entire visible southern sky every few nights, revealing unprecedented details of the universe and helping unravel some of its greatest mysteries. During a 10-year time frame, LSST will detect about 20 billion galaxies — the first time a telescope will observe more galaxies than there are people on Earth – and will create a time-lapse “movie” of the sky.
This data will help researchers better understand dark matter and dark energy, which together make up 95 percent of the universe, but whose makeup remains unknown, as well as study the formation of galaxies, track potentially hazardous asteroids and observe exploding stars.
The telescope’s camera — the size of a small car and weighing more than three tons — will capture full-sky images at such high resolution that it would take 1,500 high-definition television screens to display just one picture.
Research scientists aren’t the only ones who will have access to the LSST data. Anyone with a computer will be able to fly through the universe, past objects 100 million times fainter than can be observed with the unaided eye. The LSST project will provide an engagement platform to enable both students and the public to participate in the process of scientific discovery.
Riot, who started on the LSST project in 2008, initially managed the camera optics fabrication planning, became the LSST deputy camera manager in 2013 and the full camera project manager in 2017. For the past three years, he has worked at LLNL and at SLAC on special assignment.
“There are important challenges getting everything together for the LSST camera. We’re receiving all of these expensive parts that people have been working on for years and they all have to fit together,” Riot said.
Wolfe, an LLNL optical engineer and the LSST camera optics subsystems manager, and Riot are pleased that the world’s largest optical lens has overcome hurdles.
“Any time you undertake an activity for the first time, there are bound to be challenges, and production of the LSST L-1 lens proved to be no different,” Wolfe said. “Every stage was crucial and carried great risk. You are working with a piece of glass more than five feet in diameter and only four inches thick. Any mishandling, shock or accident can result in damage to the lens. The lens is a work of craftsmanship and we are all rightly proud of it.
“When I joined LLNL I had no idea that it would lead to the opportunity to deliver first-of-a-kind optics to a first-of-a-kind telescope,” Wolfe said. “From production of the largest precision lens known, to coating of the largest precision bandpass filters, the LSST optics have set a new standard.”
Livermore involvement in LSST started around 2001, spurred by the scientific interest of LLNL astrophysicist Kem Cook, a member of the Lab team that previously led the search for galactic dark matter in the form of Massive Compact Halo Objects.
However, LLNL participation in LSST quickly became centered on the Lab’s expertise in large optics, built over decades of developing the world’s largest laser systems. Starting in 2002, LLNL optical scientist Seppala, who helped design the National Ignition Facility, made a series of improvements to the optical design of LSST leading to the 2005 baseline design. This consisted of three mirrors, the two largest in the same plane so they could be fabricated from the same piece of glass, and three large lenses, as well as a set of six filters that define the color of the images recorded by the 3.2-gigapixel camera detector.
Construction on LSST started in 2014 on El Peñon, a peak 8,800 feet high along the Cerro Pachón ridge in the Andes Mountains, located 220 miles north of Santiago, Chile.
Financial support for LSST comes from the National Science Foundation (NSF), the U.S. Department of Energy’s Office of Science, and private funding raised by the LSST Corporation. The NSF-funded LSST Project Office for construction was established as an operating center under management of the Association of Universities for Research in Astronomy. The DOE-funded effort to build the LSST camera is managed by the SLAC National Accelerator Laboratory.
The camera system for LSST, including the three lenses and six filters designed by LLNL researchers and built by Lab industrial partners, will be shipped from SLAC to the telescope site in Chile in early 2021
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Lawrence Livermore National Laboratory (LLNL) is an American federal research facility in Livermore, California, United States, founded by the University of California, Berkeley in 1952. A Federally Funded Research and Development Center (FFRDC), it is primarily funded by the U.S. Department of Energy (DOE) and managed and operated by Lawrence Livermore National Security, LLC (LLNS), a partnership of the University of California, Bechtel, BWX Technologies, AECOM, and Battelle Memorial Institute in affiliation with the Texas A&M University System. In 2012, the laboratory had the synthetic chemical element livermorium named after it.
LLNL is self-described as “a premier research and development institution for science and technology applied to national security.” Its principal responsibility is ensuring the safety, security and reliability of the nation’s nuclear weapons through the application of advanced science, engineering and technology. The Laboratory also applies its special expertise and multidisciplinary capabilities to preventing the proliferation and use of weapons of mass destruction, bolstering homeland security and solving other nationally important problems, including energy and environmental security, basic science and economic competitiveness.
The Laboratory is located on a one-square-mile (2.6 km2) site at the eastern edge of Livermore. It also operates a 7,000 acres (28 km2) remote experimental test site, called Site 300, situated about 15 miles (24 km) southeast of the main lab site. LLNL has an annual budget of about $1.5 billion and a staff of roughly 5,800 employees.
LLNL was established in 1952 as the University of California Radiation Laboratory at Livermore, an offshoot of the existing UC Radiation Laboratory at Berkeley. It was intended to spur innovation and provide competition to the nuclear weapon design laboratory at Los Alamos in New Mexico, home of the Manhattan Project that developed the first atomic weapons. Edward Teller and Ernest Lawrence, director of the Radiation Laboratory at Berkeley, are regarded as the co-founders of the Livermore facility.
The new laboratory was sited at a former naval air station of World War II. It was already home to several UC Radiation Laboratory projects that were too large for its location in the Berkeley Hills above the UC campus, including one of the first experiments in the magnetic approach to confined thermonuclear reactions (i.e. fusion). About half an hour southeast of Berkeley, the Livermore site provided much greater security for classified projects than an urban university campus.
Lawrence tapped 32-year-old Herbert York, a former graduate student of his, to run Livermore. Under York, the Lab had four main programs: Project Sherwood (the magnetic-fusion program), Project Whitney (the weapons-design program), diagnostic weapon experiments (both for the Los Alamos and Livermore laboratories), and a basic physics program. York and the new lab embraced the Lawrence “big science” approach, tackling challenging projects with physicists, chemists, engineers, and computational scientists working together in multidisciplinary teams. Lawrence died in August 1958 and shortly after, the university’s board of regents named both laboratories for him, as the Lawrence Radiation Laboratory.
Historically, the Berkeley and Livermore laboratories have had very close relationships on research projects, business operations, and staff. The Livermore Lab was established initially as a branch of the Berkeley laboratory. The Livermore lab was not officially severed administratively from the Berkeley lab until 1971. To this day, in official planning documents and records, Lawrence Berkeley National Laboratory is designated as Site 100, Lawrence Livermore National Lab as Site 200, and LLNL’s remote test location as Site 300.
The laboratory was renamed Lawrence Livermore Laboratory (LLL) in 1971. On October 1, 2007 LLNS assumed management of LLNL from the University of California, which had exclusively managed and operated the Laboratory since its inception 55 years before. The laboratory was honored in 2012 by having the synthetic chemical element livermorium named after it. The LLNS takeover of the laboratory has been controversial. In May 2013, an Alameda County jury awarded over $2.7 million to five former laboratory employees who were among 430 employees LLNS laid off during 2008. The jury found that LLNS breached a contractual obligation to terminate the employees only for “reasonable cause.” The five plaintiffs also have pending age discrimination claims against LLNS, which will be heard by a different jury in a separate trial. There are 125 co-plaintiffs awaiting trial on similar claims against LLNS. The May 2008 layoff was the first layoff at the laboratory in nearly 40 years.
On March 14, 2011, the City of Livermore officially expanded the city’s boundaries to annex LLNL and move it within the city limits. The unanimous vote by the Livermore city council expanded Livermore’s southeastern boundaries to cover 15 land parcels covering 1,057 acres (4.28 km2) that comprise the LLNL site. The site was formerly an unincorporated area of Alameda County. The LLNL campus continues to be owned by the federal government.