Cross sections for the 7 Be͑p, g͒ 8 B reaction have been measured for E c.m. 0.35 1.4 MeV using radioactive 7 Be targets. Two independent measurements carried out with different beam conditions, different targets, and detectors are in excellent agreement. A statistical comparison of these measurements with previous results leads to a restricted set of consistent data. The deduced zeroenergy S factor S͑0͒ is found to be 15%-20% smaller than the previously recommended value. This implies a 8 B solar neutrino flux lower than previously predicted in various standard solar models.[S0031-9007(97)

We have measured the cross section of the 7Be(p,gamma)8B reaction for E(c.m.) = 185.8, 134.7, and 111.7 keV using a radioactive 7Be target (132 mCi). Single and coincidence spectra of beta+ and alpha particles from 8B and 8Be* decay, respectively, were measured using a large acceptance spectrometer. The zero energy S factor inferred from these data is 18.5+/-2.4 eV b and a weighted mean value of 18.8+/-1.7 eV b (theoretical uncertainty included) is deduced when combining this value with our previous results at higher energies.

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The ' C decay of Ra has been reinvestigated, using an 85 MBq activity ' U source radiochemically separated, a Si barrier detector, and a superconducting magnetic spectrometer. In a 16 days counting run, 210 ' C events were recorded. The ' C particles energy value 30.930+0.090 MeV was found and an upper limit b~2X10 ' was estimated for the ' C branching ratio to the 'Pb first excited state; the branching-ratio value to the 'Pb ground state, thus equal to the total branching ratio, was found to be b =A, , /A. =(2.31+0.31)X 10

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Batch experiments have been carried out to measure K d values, their variations, and some other parameters for radionuclides of interest in safety assessments including long-lived β/γ fission products and α emitters, such as Ra and the light actinides. The parameters investigated were mainly the concentrations of the elements competing with the radionuclides and the pH of the aqueous phases. The systems studied were as close as possible to those that could reasonably be expected to be encountered in a surface/near surface radioactive waste repository. A number of partition mechanisms are discussed.

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