The National Laser Users' Facility (NLUF) Celebrates its 35th Anniversary

December 2014

NLUF group from the University of Michigan performing experiments on the Omega Laser Facility

In 1979, the U.S. Department of Energy/National Nuclear Security Administration (DOE/NNSA) designated the Laboratory for Laser Energetics (LLE) at the University of Rochester (UR) as the National Laser Users' Facility (NLUF). This facility affords NNSA numerous opportunities to support essential academic research important to their mission to help maintain a safe, secure, and effective stockpile without the production of new fissile material or underground nuclear testing.

The establishment of NLUF has made it possible for the high-power laser systems at LLE to be extended to the entire scientific community. Through this program, two of the world's most-powerful laser systems, OMEGA and OMEGA EP, are accessible to conduct basic research experiments in high-energy-density physics and laser–matter interactions, as well as provide research experience to maintain a corps of scientists specially trained to meet the nation's future needs in these areas of science and technology.

OMEGA is a 60-beam ultraviolet Nd:glass laser capable of producing ultraviolet laser pulses with a total peak power of approximately 30 trillion watts and a total energy up to 30,000 joules; OMEGA EP is a four-beam Nd:glass laser capable of producing ultraviolet pulses with total energy in the range of 10,000 to 30,000 joules. Two of the OMEGA EP laser beams can be configured as high-energy petawatt (HEPW) laser beams that produce infrared laser pulses with peak power in excess of a thousand trillion watts (petawatt). The HEPW beams can be directed to either the OMEGA or OMEGA EP target chambers. An extensive array of plasma and laser diagnostics is key to the facility's scientific productivity. More than 200 state-of-the-art optical, particle, x-ray, and nuclear diagnostic systems are currently available for experiments at the facility.

Dr. Mario Manuel was selected as the recipient of the 2014 Marshall N. Rosenbluth Outstanding Doctoral Thesis Award by the American Physical Society, Division of Plasma Physics. Manuel's thesis was based on work conducted under an National Laser Users Facility grant at the Omega Facility.

Over the past 35 years, scientists and students from academic institutions, industrial research establishments, and government laboratories have participated in a broad range of experiments on behalf of NLUF. Approximately two-thirds of the Omega Laser Facility operating time is dedicated to external users. Each year, ~600 users participate in research at the Omega Laser Facility. In addition to investigations of inertial fusion physics, approved experiments have been conducted in plasma physics, x-ray laser physics, x-ray ultraviolet (XUV) spectroscopy, and instrumentation development.

Twenty-three proposals were submitted in response to the NLUF solicitation and 13 proposals were selected for the FY13–FY14 NLUF Program. A new solicitation for experiments to be conducted in FY15–16 was recently completed.

The Department of Energy's Office of Inertial Fusion funds the operation of NLUF, thereby making it possible for researchers to conduct experiments without a direct facility charge. In addition, the Department of Energy provides research funds directly to users for experiments in inertial fusion and related scientific areas. A full-time manager, who reports to the LLE Director, administers NLUF. All proposals are reviewed by the NLUF Steering Committee, which ranks them according to scientific merit. The President of the University of Rochester, with Department of Energy approval, appoints the Committee. Members include outstanding scientists from universities, industry, and government who encourage a broad range of studies in fields ranging from medicine to astrophysics.

Data acquired in FY14 and currently under analysis include magnetic reconnection, plasma kinetic effects on inertial confinement fusion (ICF) implosions, the behavior of plasma jets, the stopping of ions in plasmas, cross sections of nuclear reactions relevant to stellar nucleosynthesis, and developing new diagnostics. This work focuses on basic physics issues, concerns directly relevant to the future success of ignition experiments at the National Ignition Facility (NIF), and topics connected to high-energy-density (HED) physics and the physics of fields generated by laser–plasma interaction. These NLUF experiments have provided unique research opportunities in HED physics for graduate and undergraduate students and current NLUF data will appear in major parts of upcoming theses. Thirty-five years of investigative studies by NLUF have produced a significant testing ground for seasoned HED physics researchers to share their history, progress, and foresight, and for young scientists interested in acquiring the knowledge required for a viable, long-term fusion-energy source.

An independently managed Omega Laser Facility Users Group (OLUG), including over 300 scientists from 32 universities and 15 national research centers, facilitates communications among the users and between the user community, facility, and the broader scientific community. OLUG conducts an annual workshop at LLE with the following goals: (1) define improvements to the capabilities and operation of the facility that would advance research opportunities for all users and (2) provide an opportunity for young researchers to present their research in a very interactive yet informal setting. The research involves a variety of areas, which include inertial fusion, laboratory astrophysics, radiation hydrodynamics, plasma nuclear physics, hydrodynamic instabilities, studies of the equation of state of materials under ultrahigh pressures, plasma physics, extreme ultraviolet spectroscopy, and high-temperature and high-density plasma diagnostic development.