CERN work casts doubt on particle theory - C&EN Global Enterprise

First Page Image. In an experiment that underscores the volatility of elementary particle physics, scientists at the European Organization for Nuclear...
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CERN work casts doubt on particle theory In an experiment that underscores the volatility of elementary particle physics, scientists at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland, have obtained results that could require major additions to the most popular theory of interparticle forces. This theory, developed in 1967 by Dr. Steven Weinberg of Harvard University, and independently by Dr. Abdus Salam of Imperial College, London, is a unified mathematical description of electromagnetism and the weak interactions responsible for beta decay in radioactive nuclei (C&EN, Nov. 14,1977, page 21). Among the theory's many predictions is the existence of a new kind of weak force, called the neutral current interaction. This prediction was confirmed in 1973 when the neutral current interaction was revealed in experiments on the collisions of neutrinos with atomic nuclei and electrons. Subsequent experiments have verified the theory's predictions in detail. The recent CERN experiments, however, were investigating the neutral current interactions of neutrinos and electrons at the highest energy yet, 25 GeV. Some 128,000 interaction events were recorded. According to the Weinberg-Salam theory, only one or two of the events should have been the sought-for neutrino-electronneutral current type. Instead the experiment found 10 such events. The discrepancy seems too large to be a statistical fluke, and it is totally inconsistent with the theory as it now stands. Weinberg tells C&EN that there are three possible explanations for the result. One, of course, is that the experiment is wrong. Earlier the CERN scientists, as well as an independent group at CERN, had done the same experiment at lower neutrino collision energy and had obtained results consistent with the theory. Very soon, Weinberg says, an experiment at the Fermilab accelerator in Batavia, 111., will be able to verify or contradict CERN's anomalous high-energy results. A second possibility, he says, is that the experiment is correct, but that the anomalous events have nothing to do with the neutral current interaction. Instead, they could signal the existence of some new, hitherto unsuspected particle, whose effect would be felt only in the higher energy collisions. Finally, says Weinberg, the exper6

C&EN May 15, 1978

iment could, in fact, be evidence for a second type of neutral current interaction not included in the original theory. It would involve only the neutrino, the electron, and their close relatives, but not the proton and neutron. If this possibility is true, however, then CERN's earlier lowenergy experiments must have been wrong. D

U.S. use of imported oil to continue growth The growth rate of U.S. energy consumption is slowing, but not enough to make even a slight dent in the country's dependence on imported oil, according to the latest figures from the Department of Energy. In its first annual report to Congress, DOE's Energy Information Administration projects that total energy consumption will increase from 1975 to 1985 at 2.6 to 3.2% annually, and from 1985 to 1990 at 2.0 to 2.5% annually. Energy consumption has been growing at an annual rate of 3.7% for the past three years. However, according to other EIA projections, U.S. energy production will increase at a slower rate than consumption—about 2% annually

from 1975 to 1985. And after 1990 this growth rate will decline, even though in 1990 it's projected that offshore areas and Alaska will account for 36% of U.S. oil production, compared with 19% in 1977. But increased production from these sources will be more than offset by declines in crude oil production in the lower 48 states. Thus, U.S. dependence on imports, mainly oil, will continue to grow. EIA projects that by 1985 imports will be 80% higher than they were in 1975, reaching a level of 9 million to 13 million bbl a day. By 1990 imports could reach 10 million to 15 million bbl daily. Natural gas production, which began to decline in 1973, will continue its downward trend, EIA says. The decline in natural gas production is expected to be too large to be offset by increased Alaskan or offshore production, imports, or synthetic substitutes from coal. Coal production, on the other hand, is forecast to rise 4 to 5% annually through 1990, reaching a level of about 1.25 billion tons. And nuclear electric power will provide nearly 13% of total U.S. energy production in 1990, compared to 8.5% in 1985 and about 3% in 1975. Geothermal and hydroelectric power will provide 7% of the 1990 energy supply. D

Gas from solid waste pre ects get under way Two projects to turn organic solid wastes into methane fuel are getting under way this month, albeit in different phases of development. One is a demonstration plant, located at Pompano Beach, Fla., that converts urban organic solid waste and municipal sewage sludge into methane-rich gas. The other is a full-scale facility—the largest in the U.S.—that will convert animal feedlot wastes into methane and highprotein feed supplements. The Florida demonstration project, dedicated early this month, was built by Waste Management Inc. under a $3.6 million contract from the Department of Energy. It uses an anaerobic digestion process to convert up to 100 tons per day of solid waste and sludge into 300,000 cu ft of methane and 300,000 cu ft of carbon dioxide. The plant will be run as a two- to four-year experiment to determine the commercial feasibility of the conversion process. It is adjacent to Waste Management's solid waste reduction center, a 65 ton-per-hour solid waste shredding facility that will supply the plant with pulverized organic solid waste material. If the demonstration plant is successful, a

larger, 1000 ton-per-day plant is planned. Such a plant could produce enough methane to replace natural gas in 10,000 homes, at the same time reducing the volume of solid waste and sludge 70%. The other solid waste-to-methane project getting a big federal boost is an animal feedlot bioconversion facility to be built at Lamar, Colo. The Department of Agriculture, through its Farmers Home Administration, will provide a $14.2 million loan to finance the project. The plant, to be built by the City of Lamar Utilities Board, will produce 1.2 million cu ft of methane per day from 350 tons of animal wastes. The methane will be burned in the city's electrical generation plant, heat from which, in turn, will be used to incubate the anaerobic digestion process that produces the methane. This methane will supply about 40% of the energy requirements of the 10,000 people living in the area. In addition, 130 tons per day of protein feed supplement will be produced from the residue of the digestion process. This supplement, fed to the livestock in the feedlots, is expected to reduce their feeding costs $12 to $18 per head. D