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British efforts to discover the missing mass of the Universe are to receive a cash injection of £5.2 million (US$8.3 million) over the next four years in an attempt to consolidate Britain's position among the top research groups in the field.

Research into dark matter, which makes up 90 per cent of the mass of our Galaxy, has the personal backing of Ian Halliday, chief executive of the Particle Physics and Astronomy Research Council which is giving the money. Halliday believes it to be a field in which Britain could win a physics Nobel prize (see Nature 392, 217; 1998).

Neil Spooner, a spokesman for the British dark-matter project, a collaboration between Imperial College, London, the University of Sheffield and the Central Laboratory of the Research Councils, says the 20 per cent increase in funds is “excellent news” — although he acknowledges that a 60 per cent increase had been requested.

More funds, however, will be one of the outcomes if the group comes up with positive results. It has also applied to the government's £600 million Joint Infrastructure Fund for £3.8 million for new laboratory facilities.

British efforts to detect weakly interacting massive particles (WIMPs), believed to be a constituent of dark matter, are housed in Yorkshire, down a one-kilometre-deep disused salt-mine where background radiation levels are low; one of the biggest challenges for dark-matter researchers is in distinguishing WIMPs from natural background radiation.

The new funds will be used to build several detectors, including a 50-kilogram sodium-iodide detector, and two liquid-xenon detectors known as ‘Zeplin’. The group also plans to develop a xenon-gas-based detector called ‘Drift’ to measure the direction of dark-matter particles.

Despite the cash injection, Spooner says, the British group remains less well funded than its two main competitors, a group at the University of Rome and one based on a collaboration between researchers at the University of California, Berkeley, and Stanford University.

None of the groups has so far claimed to have discovered dark matter. The US group has only recently overcome various technical problems with its cryogenic detectors, and is expecting to start gathering data this year.

The Rome group, which uses a 100-kilogram sodium-iodide detector, has recorded an apparent seasonal variation in its radiation counts, with more counts in summer than in winter, which is one indication of a dark-matter signal. But Peter Smith of the Rutherford Appleton Laboratory, the founder of the British group, says more research is needed before the variation is confirmed.

While welcoming the research council funds, one leading particle physicist believes that research grants should be driven by exciting science rather than Nobel prizes, which, he thinks may have outlived their relevance to the way science works today. “Science Nobel prizes are awarded to individuals. But much research today, particularly in particle physics, involves extensive collaborations,” he says.

The difficulty of identifying suitable recipients, he adds, would be apparent if the UK group were to win the physics prize for discovering dark matter, as this group includes researchers from the United States, Russia and Italy.