A second experiment clocking the speed of subatomic particles using a GPS timing receiver has reconfirmed the revolutionary September results — the neutrinos moved faster than the speed of light, according to an announcement from the European Organization for Nuclear Research (CERN).
“One key test was to repeat the measurement with very short beam pulses from CERN,” the agency noted in a press release on its website. “This allowed the extraction time of the protons, that ultimately lead to the neutrino beam, to be measured more precisely… The new measurements do not change the initial conclusion.
Septentrio's precise-timing GPS receiver PolaRx2eTR features prominently in the OPERA experiment. Following the OPERA collaboration's presentation at CERN on September 23, inviting scrutiny of their neutrino time-of-flight measurement from the broader particle physics community, the collaboration has rechecked many aspects of its analysis and taken into account valuable suggestions from a wide range of sources, CERN stated on its website.
The beam sent from CERN consisted of pulses three nanoseconds long separated by up to 524 nanoseconds. Some 20 clean neutrino events were measured at the Gran Sasso Laboratory, and precisely associated with the pulse leaving CERN. This test confirms the accuracy of OPERA's timing measurement, ruling out one potential source of systematic error. "Nevertheless, the observed anomaly in the neutrinos' time of flight from CERN to Gran Sasso still needs further scrutiny and independent measurement before it can be refuted or confirmed," CERN stated.
The OPERA experiment observes a neutrino beam from CERN 730 kilometers away at Italy’s INFN Gran Sasso Laboratory. The OPERA result is based on the observation of more than 15,000 neutrino events measured at Gran Sasso, and appears to indicate that the neutrinos travel at a velocity 20 parts per million above the speed of light, nature’s cosmic speed limit. "Given the potential far-reaching consequences of such a result, independent measurements are needed before the effect can either be refuted or firmly established. This is why the OPERA collaboration has decided to open the result to broader scrutiny," CERN stated.