USA prepare a 20-year roadmap for basic energy sciences facilities

Ray Orbach, the Director of the Office of Science at the Department of Energy, received a detailed report from a committee chaired by Geraldine Richmond (University of Oregon) and Sunil Sinha (University of California, San Diego). The committee primarily looked at the synchrotron radiation and neutron provision for the USA. For the Journal of Synchrotron Radiation readership, we summarize the main aspects of recommendations affecting the synchrotron radiation community.

The committee recognized the importance of four DOE light sources for the country's scientific and technological enterprise and stressed that, in order to continue producing cutting-edge science, upgrades at these facilities are needed in the near future for them to remain at the forefront of light-source activities. DOE should aggressively pursue a light source facilities initiative that involves a coordinated effort among the four light sources, namely:

The National Synchrotron Light Source (NSLS) and the Office of Basic Energy Sciences (BES) to formulate a plan for construction of a third-generation ring at NSLS instead of the current very ambitious plan for NSLS II which is a fourth-generation source. The committee commented that the scope of the current NSLS II proposal is too broad and does not take account of DOE's national facilities portfolio.

The Advanced Photon Source (APS): phase I and II upgrades were strongly supported, namely (a) to complete the installation of the remaining beamlines and to optimize the earlier beamlines, and (b) to optimize the source by means of innovative insertion devices and accelerator development.

The Advanced Light Source (ALS): support of their upgrade proposal to go to full energy injection and higher current, as well as to replace obsolescent insertion devices (IDs) and beamlines with state-of-the-art IDs and new beamlines.

Stanford Synchrotron Radiation Laboratory (SSRL) is currently undergoing an upgrade that will make it a third-generation X-ray source.

Among the new facilities in the immediate future, one proposal that ranked very highly in both quality of proposed science and facility readiness was the Linear Coherent Light Source (LCLS). This free-electron laser (FEL) facility is essential for exploring future science using intense femtosecond coherent X-ray beams. The knowledge gained from operation of this facility is critical for providing preliminary assessments of many science drivers for these new intense coherent fast X-ray sources and providing critical guidance to the planning and ultimate success of several future proposed X-ray FEL (XFEL) sources that offer exciting new prospects for future scientific endeavors in BES. The BESAC subcommittee enthusiastically supported this project.

The committee commented that if predicted successes of LCLS are realised, the community will demand a full-scale, state-of-the-art, fully coherent, superbright, multiplexed, diffraction-limited facility, the so called `Greenfield' XFEL. The committee feels that the appropriate research and development that could enable this facility must go forward. Critical areas that need improvement include gun technology, detector optimization and electron beam stability, as well as continued advances in the scientific case. Within five years, experience with XFEL science and technology should mature to the point that a decision can be made on the scope of any future Greenfield XFEL facility.