Chalk River

Averages of the values reported by W. H. Walker, Chalk River Report CRRP-916, 16 (I960) S. Katcoff, Nucleonics 10, 201 (i960) ... 

Feller, M.C. In Proceedings of the 10th Conf on Fire and Forest Meteorology. Forestry Canada. Chalk River, Ontario, 1989. pp 126-135. 

Sears VF (1984) Thermal-neutron scattering lengths and cross-sections for condensed matter research. Chalk River Nuclear Laboratories, Chalk River... 

Atomic Energy of Canada. 1992. Proceedings of the fetal dosimetry workshop held in Chalk River, ON (Canada), 25-26 June 1991. Chalk River, Ontario Chalk River Nuclear Labs, Atomic Energy of Canada. NTIS/DE94-622280. AECL-10578. 

RBS is based on collisions between atomic nuclei, and it involves measuring the number and energy of ions in a beam which backscatter after colliding with atoms in the near-surface region of a sample. The use of scattering as an analysis tool led to the first in situ chemical analysis of the lunar surface during the landing of Surveyor V. The use of particle accelerators as an a-source was the next powerful step made in Chalk River (Canada) and Arus (Denmark). 

Groeneveld, D. C., 1972, The Thermal Behavior of a Heated Surface at and Beyond Dryout, AECL-4309, Chalk River, Canada. (4)... 

G. R. and E. M. Burbidge, W. A. Fowler and F. Hoyle (B2FH) publish influential article describing nuclear processes which generate essentially all nuclear species by reactions in stars or interstellar medium. Similar ideas put forward by A. G. W. Cameron in a Chalk River internal report. 

Taber, Alberta Los Angeles Man, Baldwin Hills 26000 OxA-773 Chalk River 3390 90 3550 500 3560 [22 000-60 000 on geological grounds]... 

Neuburg, H.J. Atherley, J.F. Walker, L.G. "Girdler-Sulfide Process Physical Properties," AECL-5702. Chalk River Nuclear Laboratories Chalk River, Ontario, May 1977. 

Linzon reported snb symptoms on white pine after several days of wet weather followed by a continuous sunny period. Symptoms were noted several times during the 1957-1964 growing seasons at Chalk River, Ontario, but time of occurrence did not correlate well with peak oxidant concentrations. Berry and Ripperton observed emergence tipbum on susceptible trees in West Virginia several days after oxidant peaks of 0.065 ppm. They found that container-grown susceptible pine clones were protected from injury if placed in a chamber supplied with charcoal-filtered air. 

Both of these routes require immobilization of the material to ensure a low rate of solution by water both types of immobilization involve a large chemistry component. The early approach of vitrification pioneered by AECL at Chalk River some 20 years ago has stood the test of time (7) and has now been adopted and further developed internationally for handling separated waste. A variety of techniques will be explored for the immobilization of fuel. 

We have focused on the lower bound method, but density matrix research has moved forward on a much broader front than that. In particular, work on the contracted Schrodinger equation played an important role in developments. A more complete picture can be found in Coleman and Yukalov s book [23]. It has taken 55 years and work by many scientists to fulfill Coleman s 1951 claim at Chalk River that except for a few details which would be easily overcome in a couple of weeks—the A-body problem has been reduced to a 2.5-body problem ... 

Elliot, A.J. Rate constants and G-values for the simulation of light water over the range 0-300°C . Report AECL-11073, A.E.C.L. Chalk River, Canada, 1994. 

Kudoh, H. Katsumura, Y. In Ion-Beam Radiation Chemistry in Radiation Chemistry Present Status and Future Trends , Jonah, C.D. Rao, B.S.M., Eds. Elsevier London, 2002 37 pp. Elliot, A.J. Chenier, M.P. Ouellette, D.C. Koslowsky, V.T. J. Phys. Chem. 1996, 100, 9014. McCracken, D.R. Tsang, K.T. Laughton, P.J. Aspects of the Physics and Chemistry of Water Radiolysis by Fast Neutrons and Fast Electrons in Nuclear Reactors . AECL Publication 11895, Atomic Energy of Canada Limited Chalk River, Ontario, 1998. 

Cameron, A. G. W. (1957) Stellar Evolution, Nuclear Astrophysics, and Nucleogenesis (CRL-41 AECL-454). Chalk River, Ontario Atomic Energy of Canada, Ltd. 

Exotic Nuclei and Their Decay. As reported by J.C. Hardy (Chalk River Nuclear Laboratories. Atomic Energy of Canada, Ltd.), recent advances in nuclear accelerators and experimental techniques have led to an increasing ability to synthesize new isotopes. As isotopes are produced with more and more extreme combinations of neutrons and protons in their nuclei, new phenomena are observed, and the versatility of the nucleus is increased as a laboratory for studying fundamental forces. Hardy reports that, among the newly discovered decay modes are (1) proton radioactivity, (2) triton, two-proton, two-neutron, and three-neutron decays that are beta-delayed, and (3) 14C emission m radioactive decay, Precise tests of the properties of the weak force have also been achieved. 

Many examples of the application of radiotracers to environmental problems exist, and so we have selected only a few of the more interesting ones to discuss. Barry (1971) used 41 Ar, a short-lived gas found in reactor stack effluents, to trace the dispersion of stack effluent from the Chalk River nuclear reactor and relate it to conventional dispersion models. The 41Ar concentrations in the air at various distances from the emitting stack were measured by circulating the air through a counter consisting of layers of plastic scintillator. The (3 particles emitted in the decay of 41Ar were detected by the plastic scintillators. The detectors were... 

In the fall of 1999, a pilot zeolite barrier was installed at the West Valley Demonstration Project (WVDP) in Western New York. The WVDP is an environmental management project being conducted by the U.S. Department of Energy (DOE) with the cooperation of the New York State Energy Research and Development Authority. Details of the installation are reported by Moore et al. (2000). The clinoptilolite material used in the barrier had previously been studied by Cantrell (1996) for a proposed installation at the DOE Hanford Facility, by Fuhrmann et al. (1995) for use at the WVDP, and by Lee et al. (1998) for the 1998 installation at Chalk River, Ontario. The range of previously estimated distribution coefficients (Kd) was from 650 mL/g (Fuhrmann et al.) to 2600 mL/g (Cantrell). The variation across these studies is most likely attributable to differences in the source water and experimental conditions, although the data interpretation... 

Clegg, L. J Coady, J. R., "Radioactive Decay Properties of CANDU fuel Volume 1. The Natural Uranium Fuel Cycle," AECL-4436/1, Chalk River, Ontario, Canada, 1977. 

Melnyk, T.W. Walton, F.B. Johnson, L.H. "High-Level Waste Glass Field Burial Tests at CRNL. The Effect of Geochemical Kinetics on the Release and Migration of Fission Products in a Sandy Aquifer", AECL-6836, Chalk River, Ontario, Canada, 1983. 

USING THE ISOLDE-3 MASS SEPARATOR The high resolution of ISOLDE 3 (design value = 3.10 ) enables direct mass measurements. Such measurements were proposed at the Workshop "On-line in 1984 and beyond" held at Zinal [ZIN84]. In these experiments, the transmission signals have to be split in order to obtain the necessary accuracy. However, the feasibility of this technique has already been demonstrated by the Chalk River group [SHA84]. 

The Tandem Accelerator Superconducting Cyclotron facility at Chalk River, which is nearing completion of phase 1, will be capable of accelerating all ions to at least 10 HeV/u. Together with the on-line isotope separator it will provide a powerful means of studying exotic nuclei ... 

During phase 1 of construction of the Tandem Accelerator Superconducting Cyclotron (TASCC) facility at Chalk River, the existing tandem accelerator was reversed, a superconducting cyclotron built and some 60 metres of beam-transport line installed to connect the two and to deliver beams to an interim target line" The result, which required an appreciable building extension, is shown in figure 1 ... 

When it reaches its full capability, TASCC will accelerate all ions between lithium and uranium to energies up to 50 MeV/u and 10 MeV/u, respectively, It will feed some major pieces of apparatus the Q3D magnetic spectrometer, the isotope separator, a growing array of gas and solid-state detectors housed in a 1.5 m diameter scattering chamber, and the 8ir" Y-ray spectrometer [AND 84], All are currently operational except the 8ir spectrometer, which is being built by a consortium of Canadian universities and AECL Chalk River, with completion scheduled for late 1986. It will comprise two subsystems i) a spin spectrometer of 72 bismuth germanate (BGO) detectors, and ii) an array of 20 Compton-suppressed hyperpure (HP) Ge detectors. 

Fig. 2. Cutaway view of the Chalk River superconducting cyclotron.

The Chalk River isotope separator has been operating on-line with the tandem accelerator since April 1979, When the tandem shut down in 1982, the separator was completely dismantled and reassembled with some improved components at its present location, where it will be on-line with TASCC (see figure 1), It is now working again and, although recommissioning is not yet complete, it has already achieved some of the excellent performance characteristics met before the move, A picture of the relocated instrument appears as figure 3. 

Like most other on-line isotope separators (ISOLs), the Chalk River device was previously operated with its ion source essentially in line with the primary accelerator beam so that nuclei produced by reactions in a target would recoil directly into the ISOL ion source. We used a FEBIAD ion source [KIR/6], which was characterized by long cathode lifetime and good efficiency for a wide variety of elements. 

Fig. 4. The CO-N2 doublet at mass 28 measured with the Chalk River ISOL and a FEBIAD ion source the resolving power is 20,000. With a slit-geometry source 16,000 has been obtained. (The separation between the two peaks is 10.5 MeV.)...

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