作者j0958322080 (Tidus)
看板Physics
標題Re: [新聞] faster-than-light neutrino
時間Sat Feb 25 22:36:20 2012
聽說是新的：
http://tinyurl.com/7whjwsr
The CERN particle physics laboratory in Geneva has confirmed Wednesday's
report that a loose fiber-optic cable may be behind measurements that seemed
to show neutrinos outpacing the speed of light. But the lab also says another
glitch could have caused the experiment to underestimate the particles' speed.
In a statement based on an earlier press release from the OPERA
collaboration, CERN said two possible "effects" may have influenced the
anomalous measurements. One of them, due to a possible faulty connection
between the fiber-optic cable bringing the GPS signals to OPERA and the
detector's master clock, would have caused the experiment to underestimate
the neutrinos' flight time, as described in the original story. The other
effect concerns an oscillator, part of OPERA's particle detector that gives
its readings time stamps synchronized to GPS signals. Researchers think
correcting for an error in this device would actually increase the anomaly in
neutrino velocity, making the particles even speedier than the earlier
measurements seemed to show.
CERN's statement says OPERA scientists are studying the "potential extent of
these two effects" but doesn't indicate which source of error (if either) is
likely to outweigh the other. However, Lucia Votano, director of the Gran
Sasso laboratory, says the "main suspicion" focuses on the optical-fiber
connection. She adds that OPERA researchers deserve credit for "having
tenaciously followed this particular evidence via checks completed in the
last few days."
The two effects will get a new round of tests in May, when the two labs are
scheduled to make velocity measurements with short-pulsed beams designed to
give readings much more precise than scientists have achieved so far.
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推 waddler:不是新的 跟線沒接好那則新聞同日就有這消息了 02/25 23:22
→ j0958322080:那篇沒說到第二段後面的事吧 02/25 23:25
→ waddler:一個是數據分析時內插法可能沒做很好 一個是線沒接好 02/25 23:26
→ waddler:哪個問題大? 做實驗的應該心裡有數 科科 02/25 23:28
→ irrotation:線沒接好... 還蠻扯的 這種實驗應該要花不少錢吧... 02/25 23:53
→ irrotation:而且是全世界人都在看的... 02/25 23:54
→ yeahbo:也許是一萬條線其中一條沒接好，甚至可能只是那條線接頭 02/26 01:38
→ yeahbo:沒鎖好，偏了幾個micron... ？ 02/26 01:38
推 irrotation:我覺得扯的原因是 工業配線這種技術 不是OPEN就是CLOSE 02/27 10:28
→ irrotation:如果鬆了 應該是對應的CHANNEL沒有信號才是.. 怎麼會出 02/27 10:29
→ irrotation:現誤差的信號? 當然我沒看過那台儀器 但就有點不解 02/27 10:31
推 sunev:我也不解，不過沒找到細部的解釋 02/27 19:53