NS: Dark matter claims thrown into doubt by new data

[bystander]

Dark matter claims thrown into doubt by new data
New Scientist - 03 May 2010

Previous claims that dark matter had been detected are being called into doubt now that a powerful new experiment has failed to see any of the elusive particles.

For years, scientists running the DAMA experiment beneath a mountain in Italy have reported a seasonal variation in the number of light flashes seen in their sodium iodide target. They claim the variability is due to changes in the speed of dark matter particles streaming through the laboratory as a result of Earth's orbital motion around the sun.

In December 2009, scientists also reported two possible dark matter particle impacts in an experiment called the Cryogenic Dark Matter Search II.
...
Now, a third experiment called Xenon 100, which its makers say is even more sensitive than the other two, has failed to detect the impact of any dark matter particles, casting doubt on the earlier results. "Dark matter particles continue to escape our instruments," says Xenon 100 spokesperson Elena Aprile of Columbia University in New York.

Like DAMA, Xenon 100 is located in the underground Gran Sasso National Laboratory in Italy. But instead of sodium iodide, it uses liquid xenon as a target for dark matter particles.

http://asterisk.apod.com/vie ... 31&t=19196
http://asterisk.apod.com/vie ... 31&t=18499

[bystander]

Early Results from Large Dark Matter Detector Cast Doubt on Earlier Claims
Scientific American - 05 May 2010

The XENON100 detector in Italy should have been able to confirm previous dark matter signals.