User Program and Obtaining User Access to the NCNR
The NCNR is dedicated to providing neutron beams for use by the scientific user community in keeping with the scope and mission of its parent agency NIST. Through the NCNR, NIST maintains and operates the nuclear reactor and some associated instrumentation. The NCNR also supports a large user program. Twice a year, there is an open call for user proposals, which are submitted via an online portal. Users have commented that the web-based interface, which they must use, has improved over the past few years, making it more intuitive, stable, and user friendly. Proposals are peer-reviewed by three to five external referees for technical merit and by the NCNR beam scientists for feasibility. Proposals are required to include a list of recent publications from previous beam-time allocations. The proposals are then ranked, and awards of beam time are made by the Beam-Time Allocation Committee (BTAC). Proposals not awarded beam time are returned to the user with comments received from the referees to improve subsequent submission. The number of participants and proposals have been increasing at a rate of 6 and 10 percent per year, respectively, since 1991—a testament to the quality of the facility, the outreach efforts of the NCNR staff scientists, and the growth of the neutron-scattering community in the United States.
The NCNR User Group conducted a survey of its users in 2015 to determine what the NCNR could do to improve its service to the user community. The panel was provided with the results of that survey and the NCNR’s response to it, which was deemed satisfactory by this review panel. The chairperson of the User Group, Associate Professor Megan Robertson of the University of Houston’s Department of Chemical Engineering, described the User Program, the proposal submission and review process, and the interactions between the User Group and the NCNR management, and she provided very positive feedback on the overall operation of the NCNR and the User Program.1
1 M. Robertson, University of Houston, presentation to the panel on July 10, 2018.
Center for High Resolution Neutron Scattering
The Center for High Resolution Neutron Scattering (CHRNS) is as noted a partnership between the National Science Foundation (NSF) and the NCNR that supports seven of the NCNR’s premier neutron-scattering instruments. This partnership is critical to the NCNR’s ability to offer an effective user program because of its investments in beamline and special-environment staff and equipment. The main mission of CHRNS is to develop and operate state-of-the-art neutron-scattering instrumentation with broad applications in materials research for use by the general scientific community. Its mission, in keeping with that of the NSF and its education and outreach mission, differs slightly from that of NIST but in important ways. The ability of the NCNR, through this partnership, to meet the needs of both agencies greatly enhances the impact of the facility on the community.
CHRNS is also responsible for a significant effort in scientific support services, not least of which are the Helium-3 (3He) spin filters that are critical to the spin polarized measurements on MACS and SANS. These filters, which will also be installed on vSANS and CANDOR, require considerable technical support made possible by the CHRNS partnership.
The main mission of CHRNS is as noted to develop and operate state-of-the-art neutron-scattering instrumentation with broad applications in materials research for use by the general scientific community. The development of new capabilities provide significant benefits for the NCNR and all of its stakeholders. It also has a significant impact on the scientific output of the NCNR by providing and supporting sample environments and by providing user support before, during, and after experiments. Finally, it supports the NSF missions of education and outreach, which increases the nation’s expertise and enhances the NCNR education and outreach activities, particularly through the Summer Undergraduate Research Fellowship (SURF) and the Summer High School Intern Program (SHIP) programs as well as neutron-scattering schools run at the NCNR have helped educate students and active scientists about neutrons, thereby increasing the pool of potential users.
CHRNS also leads in user training on CHRNS instruments and in user-environment support, including ancillary laboratories and devices for controlling sample temperature (including milli-Kelvin [mK] cryogenics), pressure, magnetic field, humidity, and fluid flow. In addition, CHRNS is the epicenter of the NCNR’s education and outreach efforts, which have had high impact. NCNR staff presented a number of anecdotes of people who attended a school or summer experience at the NCNR, loved it, made their way into a doctoral program that involved neutron scattering, and became young faculty building their own neutron-scattering active groups. The large size of the neutron community in Europe, compared to that in the United States, is often attributed to the fact that European universities are much more willing to support neutron-scattering groups than are their U.S. counterparts. The fact that 33 percent of the NCNR postdoctoral researchers have made their way into faculty positions is not only an amazing feather in the NCNR’s cap, but it also bodes well for the future of neutron scattering in the United States.
Opportunities and Challenges
The current CHRNS agreement with NSF runs through 2020, and every effort needs to be made by the NCNR to ensure that it is renewed. Without CHRNS, the effectiveness of the User Program at the NCNR would suffer. The NCNR needs to act, in consort with the user community, to increase the visibility of CHRNS, to ensure that NSF and CHRNS are appropriately acknowledged in publications resulting from research performed on CHRNS instruments, and to continue and broaden the education and outreach components of CHRNS, which are absolutely essential to NSF.
The suite of CHRNS instruments, which includes many of the most exciting at the facility (MACS(II), HFBS, NSE, vSANS, and CANDOR, and so forth), is continually evolving. The vSANS is just entering the user program, and CANDOR is being installed, although its high-resolution, fixed, small-angle detector at the end of the secondary flight path has not yet been installed. The vSANS will make it possible to measure the scattering profiles of samples over an unusually wide Q-range, opening the way to studies of samples that exhibit structure at many different length scales. CANDOR is a high-throughput reflectometer that utilizes a polychromatic incident beam that provides large gains in measurable intensity. Its introduction into operations has been delayed, in part owing to the discovery that the signal from inelastically scattered neutrons in the analyzers was having a (detrimental) effect on the performance. This necessitated a redesign with cryogenically cooled analyzer crystals. The decision to halt the project and fix it, rather than to take the alternative approach to make post-hoc corrections was bold but correct. While it delays deployment of the instrument, the redesign will give much higher quality data.
nSoft is an industrial consortium, unique among neutron-scattering user facilities, designed specifically to engage industry in neutron scattering. The consortium was inaugurated in 2012 and has since grown to include 15 companies. Member companies pay $25,000 per year to participate in this program, which focuses on the development of
- Advanced measurements of industrially relevant materials and manufacturing processes and
- Member companies’ own measurement technologies, including their analytical research programs.
The nSoft director schedules beamtime on the 10 m SANS and arranges beamtime on other instruments for member companies. All nSoft research is nonproprietary, since, by law, all proprietary research must be done on a full-cost-recovery basis. Proposals for nSoft research projects that are to be performed on nSoft’s beamlines do not pass through the normal user proposal review process; instead they are approved by the member companies and NIST personnel. This procedure overcomes significant impediments to industrial use of national facilities by reducing the time required to get beam time and perform experiments and by implementing less stringent guidelines for scientific originality. The intent is to be more useful to the industrial sector, which often has to deal with significant time constraints. nSoft is an innovative concept that provides an excellent way to educate industrial concerns about the utility of neutron science and to encourage them to add it to their research toolboxes.
Though the nSoft consortium has published a few papers, including one in Nature Communications, its overall publication rate is far below that of the NCNR’s general user program. This could reflect nothing more than the newness of the program, but it could also reflect inherent reluctance of industry to publish, even though the research is nonproprietary. (The value of the research to the company’s business plan or to its customers was not judged by the panel.) Nevertheless, there are apparently no protocols in place to evaluate the effectiveness of the nSoft program, and it would be well to develop metrics which would include parameters other than publication number and citations that are acceptable to the nSoft member companies, the NIST personnel involved in nSoft, and the NCNR and NIST management. These need to be publicly available, and an independent assessment of the progress of the program needs to be made from time to time. This will provide nSoft with the information it will need to justify its continued existence. As the NCNR’s programs continue to grow, and more and more demands are placed on existing beamlines, it will be necessary for nSoft and the NCNR to develop strategies for deciding future directions.
NCNR/University Cooperative Agreements
The NCNR has cooperative agreements with the University of Delaware, the University of Maryland, the University of Indiana, and Carnegie Mellon University. Some of these agreements are quite long-standing, while others are more recent. Other universities can apply for their own cooperative agreement when calls for proposals are announced. The agreements provide NCNR funding to universities for the support of technical staff, postdoctoral researchers, and graduate students engaged in neutron science and instrumentation at the NCNR. Technical staff, including beam-line scientists and software developers, hired under this program help run the NCNR facility and are stationed at the NCNR. Most postdocs and graduate students, in contrast, are stationed at their host universities. At the moment, this program supports 9 graduate students, 6 postdocs, and 23 technical staff. It has the added benefit of outreach to university students, both undergraduate and graduate, with many postdocs being recruited to the NCNR following their graduate work. While students must focus on their thesis research to graduate, they and post-doctoral fellows do provide the NCNR with extra people to carry out research, to engage in instrument developments, and, to a lesser extent, to contribute to the operation of instrumentation on beamlines. Faculty involved in these agreements have the advantage of having an on-site representative from their group at the NCNR. It would be beneficial for the NCNR to consider increasing the number of these agreements to expand on the research being done at the facility and further diversify the academic engagement.
The NCNR fields a staff of 217, of which 103 are in condensed matter science, 44 in facilities and operations, 36 in construction, and 34 in safety and administration. There are 5 affiliated technical staff/instrument scientists per instrument to serve/collaborate with users. In addition, NCNR scientists have active research programs of their own, discussed in Chapter 0. For comparison, the world’s largest neutron user facility, the Institute Laue-Langevin in Grenoble (ILL), requires 7 technical staff/instrument scientists per instrument.
The NCNR maintains a robust safety management program that addresses radiological, occupational, and industrial hazards. Key elements of the program include management commitment and employee involvement, worksite inspections, management observations, hazard prevention and control (including planning for work involving radiological hazards), and training for staff and users. In addition to operating with a strong safety management program, the NCNR has an excellent safety record that includes no regulatory violations since the last panel assessment in 2015.
The NCNR also supports a large user program. The number of participants and proposals have been increasing at a rate of 6 and 10 percent per year, respectively, since 1991—a testament to the quality of the facility and the outreach efforts of the NCNR staff scientists
Opportunities and Challenges
Increasing security and safety demands will place strain on current staff and threaten continuing ease of access of the facility to users.