The Oscillation Project with Emulsion-tRacking Apparatus (OPERA) experiment modified their system to send a shorter burst of particles between Switzerland and Italy, finding once again particles moving faster than light. (Image credit, OPERA)

The first report in September detailed measurements by the Oscillation Project with Emulsion-tRacking Apparatus (OPERA) Collaboration of a beam containing bunches of tiny particles called neutrinos traveling between labs in Switzerland and Italy apparently 60 nanoseconds faster than light.

If the discovery were confirmed by other experiments, it would undermine Einstein's Theory of Relativity, one of the basic principles of physics which holds that nothing can exceed light-speed.

The new experiment claims to account for criticisms from other scientists in order to eliminate systematic uncertainty, specifically in regards to how many neutrinos were in the beam and for how long the beam lasted.

From Science 2.0:

These benefits come from CERN, where proton bunches have been made much shorter: down to three nanosecond long pulses. That means that OPERA can measure the speed of each detected neutrino separately! Of course, with such short pulses, the statistics of protons on target is "only" of 4x10^16, but this is still enough to reach meaningful results from the additional data.

The new experiment's results are unchanged from those announced in September though the shorter burst of particles provided a larger margin or error.

Scientists caution, however, since the experiment uses the same system as the earlier one it may be prone to the same flaws, whether accounted or unaccounted for.

From BBC News:

The error in the length of the bunches, however, is just the largest among several potential sources of uncertainty in the measurement, which must all now be addressed in turn; these mostly centre on the precise departure and arrival times of the bunches.

The next step for the findings will be independent experiments that will either reproduce or disprove the original results, as organizations in Italy, Japan, and the U.S. have announced plans to make measurements of their own.

The OPERA paper itself can be downloaded at this link, using "neuvel" as the username and password.

You can reach reporter Shea Huffman by email, or follow him on Twitter.