Updated Nucleosynthesis Constraints on Unstable Relic Particles

We revisit the upper limits on the abundance of unstable massive relic particles provided by the success of Big-Bang Nucleosynthesis calculations. We use the cosmic microwave background data to constrain the baryon-to-photon ratio, and incorporate an extensively updated compilation of cross sections into a new calculation of the network of reactions induced by electromagnetic showers that create and destroy the light elements deuterium, he3, he4, li6 and li7. We derive analytic approximations that complement and check the full numerical calculations. Considerations of the abundances of he4 and li6 exclude exceptional regions of parameter space that would otherwise have been permitted by deuterium alone. We illustrate our results by applying them to massive gravitinos. If they weigh ~100 GeV, their primordial abundance should have been below about 10^{-13} of the total entropy. This would imply an upper limit on the reheating temperature of a few times 10^7 GeV, which could be a potential difficulty for some models of inflation. We discuss possible ways of evading this problem.Comment: 40 pages LaTeX, 18 eps figure

Handling and Application of Pollen to Fruit Trees

ARTIFICIAL POLLINATION of tree fruits on a commercial basis was started in the state of Washington approximately 20 years ago. Since that time, many orchards with inadequate pollination by natural means have been pollinated artificially; these, for the most part, produced greatly increased crops as a result of the practice. In general, the increase was greatest where pollination by natural means was not satisfactory. The need for artificial pollination is most generally with apples, although some attention has been given to pears, sweet cherries and plums in recent years

Report of the Tree Fruit Branch Experiment Station, 1946; Volume 9, No. 1

Topics include abstracts, tree and crop experiments, spray experiments, fertilizer experiments, pest control, pollination, sale data, and yearly productio