NASA MIT Alpha Magnetic Spectrometer (AMS): Prepares to release first results

The scientist leading one of the most expensive experiments ever put into space says the project is ready to come forward with its first results.

The Alpha Magnetic Spectrometer (AMS) was put on the International Space Station to survey the skies for high-energy particles, or cosmic rays.

Nobel Laureate Sam Ting said the scholarly paper to be published in a few weeks would concern dark matter.

This is the unseen material whose gravity holds galaxies together.

Researchers do not know what form this mysterious cosmic component takes, but one theory points to it being some very weakly interacting massive particle (Wimp).

Although telescopes cannot detect the Wimp, there are high hopes that AMS can confirm its existence and describe some of its properties from indirect measures.

The imminent publication in an as yet undetermined journal will detail the progress of that investigation.

The Massachusetts Institute of Technology professor said the project he first proposed back in the mid-1990s had now reached an important milestone.

"We've waited 18 years to write this paper, and we're now making the final check," he told reporters.

"I would imagine in two or three weeks, we should be able to make an announcement.

"We have six analysis groups to analyse the same results. Physicists as you know - everybody has their own interpretations, and we're now making sure everyone agrees with each other. And this is pretty much done now."

Sam Ting was speaking here in Boston at the annual meeting of the American Association for the Advancement of Science (AAAS).

His $2bn machine was taken up to the ISS in 2011 - on the final mission of Shuttle Endeavour.

The seven-tonne experiment holds a giant, specially designed magnet that bends the paths of particles that fall on it.

The way they bend reveals their charge, a fundamental property that, together with information about their mass, velocity and energy, garnered from a slew of detectors, tells scientists precisely what they are dealing with.

Prof Ting said that in its first 18 months of operation, AMS had witnessed 25 billion particle events.