中微子可以超光速运动？（CERN文章_英文）

哪位同好感兴趣可以翻一下，我最近可能时间不足。
OPERA experiment reports anomaly in flight time of neutrinos from CERN to Gran Sasso
Geneva, 23 September 2011. The OPERA1 experiment, which observes a neutrino beam from CERN2 730 km away at Italy’s INFN Gran Sasso Laboratory, will present new results in a seminar at CERN this afternoon at 16:00 CEST. The seminar will be webcast at http://webcast.cern.ch. Journalists wishing to ask questions may do so via twitter using the hash tag #nuquestions, or via the usual CERN press office channels.


The OPERA result is based on the observation of over 15000 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. The collaboration’s result is available on the preprint server arxiv.org: http://arxiv.org/abs/1109.4897.

      The OPERA measurement is at odds with well-established laws of nature, though science frequently progresses by overthrowing the established paradigms. For this reason, many searches have been made for deviations from Einstein’s theory of relativity, so far not finding any such evidence. The strong constraints arising from these observations makes an interpretation of the OPERA measurement in terms of modification of Einstein’s theory unlikely, and give further strong reason to seek new independent measurements.

“This result comes as a complete surprise,” said OPERA spokesperson, Antonio Ereditato of the University of Bern. “After many months of studies and cross checks we have not found any instrumental effect that could explain the result of the measurement. While OPERA researchers will continue their studies, we are also looking forward to independent measurements to fully assess the nature of this observation.”  


       “When an experiment finds an apparently unbelievable result and can find no artefact of the measurement to account for it, it’s normal procedure to invite broader scrutiny, and this is exactly what the OPERA collaboration is doing, it’s good scientific practice,” said CERN Research Director Sergio Bertolucci. “If this measurement is confirmed, it might change our view of physics, but we need to be sure that there are no other, more mundane, explanations. That will require independent measurements.”

      In order to perform this study, the OPERA Collaboration teamed up with experts in metrology from CERN and other institutions to perform a series of high precision measurements of the distance between the source and the detector, and of the neutrinos’ time of flight. The distance between the origin of the neutrino beam and OPERA was measured with an uncertainty of 20 cm over the 730 km travel path. The neutrinos’ time of flight was determined with an accuracy of less than 10 nanoseconds by using sophisticated instruments including advanced GPS systems and atomic clocks. The time response of all elements of the CNGS beam line and of the OPERA detector has also been measured with great precision.

      "We have established synchronization between CERN and Gran Sasso that gives us nanosecond accuracy, and we’ve measured the distance between the two sites to 20 centimetres,” said Dario Autiero, the CNRS researcher who will give this afternoon’s seminar. “Although our measurements have low systematic uncertainty and high statistical accuracy, and we place great confidence in our results, we’re looking forward to comparing them with those from other experiments."

      “The potential impact on science is too large to draw immediate conclusions or attempt physics interpretations. My first reaction is that the neutrino is still surprising us with its mysteries.” said Ereditato. “Today’s seminar is intended to invite scrutiny from the broader particle physics community.”

      The OPERA experiment was inaugurated in 2006, with the main goal of studying the rare transformation (oscillation) of muon neutrinos into tau neutrinos. One first such event was observed in 2010, proving the unique ability of the experiment in the detection of the elusive signal of tau neutrinos.


来源：http://press.web.cern.ch/press/P ... s2011/PR19.11E.html
这是相关的论文，正文约20页，虽然几乎没有公式，但相信不会太容易看懂。感兴趣的可以看看。

1109.4897.pdf (4.65 MB, 下载次数: 466)

2011-9-24 09:31 上传

点击文件名下载附件

Sometimes discoveries in science turn up where you are looking for them, like finding treasure near a shipwreck. At other times they seem to appear from nowhere, as if they’ve fallen from the sky. In particle physics there are plenty of examples of both kinds, but all discoveries have one thing in common. As soon you find something new – whether it’s expected or completely out of the blue – you go back through the analysis with a fine tooth comb, making sure that you’ve missed nothing. Is there a detail you’ve forgotten? Have you overlooked some aspect that could mimic the effect of something new?

It’s at this stage that you make your results known to the jury of your peers – other scientists working in the same area who look at what you’ve done and see if they can find anything you might have missed. Then, to quote one of the famous fictional detectives, Sherlock Holmes, “when you have eliminated the impossible, whatever remains, however improbable, must be the truth”.

This is particularly the case when a result is completely unexpected. In a sense, it’s all down to detective work, and the experimenters must make sure that they are interpreting all the evidence correctly before identifying the suspect.

The curious case of the speeding neutrinos – apparently breaking nature’s speed limit of the velocity of light as they fly from CERN to the OPERA experiment in central Italy – is now open to the jury. The OPERA collaboration has been able to find no explanation in terms of the experimental set up for this effect. So the researchers have revealed what they observe to their peers through a paper posted on arXiv.org that explains all the steps from data collection to the final analysis, and through a talk at CERN. Neutrino experiments are notoriously difficult because neutrino interactions are so rare, but over the coming months – and indeed years – the teams working on similar experiments elsewhere will scrutinise their data to see if they see the same effect.

This is the way that science works all the time, not just when a surprise effect appears like an unexpected guest at a party. Results are checked by others, questions can be asked – and answered – and when everyone is satisfied that nothing has been overlooked, then the results are published. Of course, wrong results do get published and surprising effects can fade away as further experiments fail to find fresh evidence. Again, this is all part of the scientific process; far from being a straight line like a Roman road linking major discoveries, it wanders more like river that changes direction in response to the landscape it crosses,

So the OPERA results are now coming under close scrutiny in the particle physics community, and it will be fascinating to see whether they do eventually stand the test of time. Then, and only then, if the results remain, fulfilling Sherlock Holmes’s requirement, would super-fast neutrinos become established, not as science fiction, but as science fact. For now, however, we have to wait and see.

Christine Sutton

来源：http://www.quantumdiaries.org/20 ... y-my-dear-neutrino/

2011年9月23日         opera的实验表明  中微子从 neutrinos from CERN to Gran Sasso Geneva的时间 异常           现在看见翻译就晕。。。。。         貌似昨天说会在网上公布最新结果

http://arxiv.org/     暂未有公布

根据m理论，超光速目前也不成立

中微子并非超光速运动，在宇宙高能事件中，检测到中微子似乎比光子微弱领先到达地球，应是因其几乎不与任何物质发生相互作用所致（中微子只参与非常微弱的弱相互作用，具有最强的穿透力，可以连续穿越1000个地球而不被阻挡！中微子如此强悍，人类要捕捉到它会有多么困难）。如果中微子哪怕只比光子快极其微小的一点，经过广袤的宇宙空间到达地球时将会显著领先于光子。我是这样理解的，是否适当，还请高人解惑

已经证实是实验数据错误了。

有趣！

早期欧洲有实验认为中微子超真空光速运动，后来发现实验数据出错了，没有超过真空光速运动。