The XENON. dark matter detectors are checked out during assembly. Image: XENON Collaboration
On 17 June, scientists reviewing data from the XENON dark matter experiment in Italy reported finding “a surprising excess of events” that could be signs of solar axions, previously undetected sub-atomic particles generated by nuclear reactions in the Sun’s interior. Or, as reported by Science magazine, the signals could be “evidence that common particles called neutrinos are more magnetic than expected. Or the result of contamination within the detector. Or just a statistical fluke.”
“The scientists do not claim to have found dark matter,” the XENON collaboration said in a release. “Instead, they say (they) have observed an unexpected rate of events, the source of which is not yet fully understood. The signature of the excess is similar to what might result from a tiny residual amount of tritium, but could also be a sign of something more exciting — such as the existence of a new particle known as the solar axion or the indication of previously unknown properties of neutrinos.”
Uncertainty over initial results is not unusual in the ongoing search for dark matter, the as-yet-unseen material thought to pervade the universe, providing the gravitational ...