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4 | NewScientist | 29 October 2011 NEUTRINOS may move faster than light, but double-checking the results is decidedly slower – as the team prepares to submit a paper for publication. Last month the OPERA collaboration at Gran Sasso, Italy, announced that neutrinos had arrived from CERN, 730 kilometres away in Switzerland, 60 nanoseconds faster than light speed. The controversial claim triggered a flood of criticism, support and speculation from the rest of the physics world. Some OPERA team members have reservations too. Fifteen of the 160-strong collaboration did not sign their names to the preprint of the paper because they considered the results too preliminary. “I didn’t sign because I thought the estimated error was not Not so fast… correct,” says OPERA team member Luca Stanco of the National Institute of Nuclear Physics in Italy, adding he thinks it is larger than the stated 10 nanoseconds. Now it appears that the cautious voices have won out. The collaboration has begun a new set of measurements to be completed before submitting the paper to a peer-reviewed journal. The team is sending tighter bunches of particles from CERN, allowing a more precise measurement of the time it takes neutrinos to get from one lab to the other. The team will take data from 21 October to 6 November, and expect to see between 10 and 15 neutrinos over that time. “If it works, then we will have sufficient accuracy, no problem,” Stanco says. Dmitri Denisov, a physicist at Fermilab in Batavia, Illinois, says it is standard procedure to wait to publish a paper until everyone in the collaboration has signed on. “We really strive to have full agreement,” he says. “In some cases it takes months, sometimes up to a year, to verify that everyone in the collaboration is happy.” Units of change AFTER decades of argument and toil, metrologists have begun the process of tying the official definitions of four basic units to nature’s fundamental constants. Attendees of the General Conference on Weights and Measures (CGPM) in Paris, France, have unanimously agreed on a proposal that would lead to reform of the mole, kilogram, kelvin and ampere, within the international system of units (SI). The lump of metal that currently defines the kilogram is changing, while the methods used for the mole, kelvin and ampere are deemed unstable, unreliable or impractical. It’s possible to tie these units to fundamental constants, but conservatives have resisted such a switch, claiming it could cause confusion and that the extra precision is unnecessary. A vote at the next CGPM in four years is needed to confirm the switch, but proponents are thrilled. “Not a single vote against! It was unbelievable,” says Ian Mills of the University of Reading, UK. –Where two faults meet– Eastern Turkey shakes TURKEY, one of the world’s most earthquake-prone countries, shook again last weekend. The magnitude 7.2 quake struck near the country’s eastern border and has so far claimed over 350 lives. Most of the country lies on the small Anatolian plate, which is being squeezed westwards as the Arabian and Eurasian plates collide. Many of Turkey’s most severe quakes occur on one of the two faults that flank the Anatolian plate. Between 1939 and 1999 Turkey’s major earthquakes seemed to be marching westwards along the north Anatolian fault towards Istanbul. In 1999 a magnitude-7.6 quake struck near Izmit, 70 kilometres from Istanbul, killing around 17,000 people.Since 2003, however, activity has shifted southwards to the east Anatolian fault. According to the US Geological Survey, the latest quake’s epicentre was 16 kilometres north-east of Van in eastern Turkey, which places it near the junction of the two Anatolian faults. Here, tectonic activity is dominated by the Bitlis suture zone – a broad zone of compression between the Arabian and Eurasian plates. “Since [the] quake is in the junction it’s hard to know which fault was responsible,” says Kevin McCue, director of the Australian Seismological Centre in Canberra. The USGS reports that the style of tectonic movement is consistent with compressional activity within the Bitlis suture zone rather than lateral grinding along the Anatolian faults. “It will mean a more precise measurement of the time it takes neutrinos to get from Switzerland to Italy” A GROUP of scientists known for their scepticism about climate change has reanalysed two centuries’ worth of global temperature records – and found that Earth is getting hotter. The Berkeley Earth Surface Temperature (BEST) project was led by Richard Muller of the University of California, Berkeley, who told US Congress this year that global 20th-century records may contain biases towards significant warming. BEST used data from 15 sources, Sceptics agree warming is real UGUR CAN/SIPA/REX FEATURES including datasets held by US and UK government agencies and the World Meteorological Organization. The project found that land temperatures have risen by 1 °C since the 1950s – much like the three existing global temperature records, kept by NASA, the US National Oceanic and Atmospheric Administration and the British Met Office. Muller says the results have been submitted for publication in “top prestigious journals”. UPFRONT
