ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
May 2025
Nuclear Technology
April 2025
Fusion Science and Technology
Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Yuichi Ogawa, Nobuyuki Inoue, Zensho Yoshida, Kunihiko Okano
Fusion Science and Technology | Volume 24 | Number 2 | September 1993 | Pages 188-199
Technical Paper | Plasma Engineering | doi.org/10.13182/FST93-A30225
Articles are hosted by Taylor and Francis Online.
The plasma and machine parameters of a pulsed tokamak reactor with a day-long operation period have been studied, where engineering constraints such as maximum toroidal field strength are preserved at International Thermonuclear Experimental Reactor (ITER) levels so as to realize a fusion reactor with only a short-range extension of currently available technology. To provide the magnetic flux necessary to sustain a plasma current inductively for 1 day or longer, plasmas with a major radius of R > 9.5 m are necessary, and a plasma with an aspect ratio as high as A > 5 should be employed. Typical parameters are as follows: major radius R = 10 m, minor radius a = 1.85 m, plasma elongation κ = 1.8, plasma current Ip = 12.2MA, toroidal field on axis Bt >= 7.56 T, and safety factor at the plasma surface qψ = 3. A plasma volume V ∼ 1200 m3 is comparable with that of ITER, even though the major radius of a day-long operation reactor is relatively large. A very small amount of heating power (∼ 15 MW) with a heating time of only a few tens of seconds is sufficient to achieve the ignition condition. This is well within the capacity of auxiliary heating systems currently used in large tokamak devices. A confinement improvement factor (from L mode) of fL > 1.7 is required to design a reactor with a reasonable machine size and a day-long pulse duration. The operation temperature is chosen to be 〈T〉 = 20 keV with a toroidal beta βt = 2.6% (Troyon factor g = 3), which gives a fusion power Pfus = 2.5 GW even for an alpha-particle dilution nα/ne of 10%. The bootstrap current fraction is 50% or more of the total current, and current profile needed for the beta limit could be achieved with a combination ofohmic current in the plasma center region and bootstrap current in the outer region. If the maximum toroidal field is set much higher, as in proposed recent reactor designs for the Steady-State Tokamak Reactor (SSTR) and ARIES, a more attractive plasma with a larger safety factor can be designed, and the pulse length can be extended remarkably.
