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DOOOOOOM for physics..are we ?.
- Nerro
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- dave_lillis
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As for 1987a, its an interesting point you raise there Al, here are some details of the neutrinos from 1987a, note the abruptness of the neutrino graph,
ircamera.as.arizona.edu/NatSci102/NatSci...upernovaremnants.htm
Do we know for sure that the visible light and neutrinos arrived at Earth at exactly the same time, if the neutrinos are moving at C+x, then maybe x is soo tiny that they were here a few seconds or a minute or so before the visible light got here?? dunno, just thinking out loud, too many unknown variables here for me, I'm an observer not a nuclear physicist.
Dave L. on facebook , See my images in flickr
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- albertw
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Dave_Lillis wrote: haha, wouldnt it be gas if that was it, but I'd imagine they must have thought of that one.
As for 1987a, its an interesting point you raise there Al, here are some details of the neutrinos from 1987a, note the abruptness of the neutrino graph,
ircamera.as.arizona.edu/NatSci102/NatSci...upernovaremnants.htm
Do we know for sure that the visible light and neutrinos arrived at Earth at exactly the same time, if the neutrinos are moving at C+x, then maybe x is soo tiny that they were here a few seconds or a minute or so before the visible light got here?? dunno, just thinking out loud, too many unknown variables here for me, I'm an observer not a nuclear physicist.
Supernovas happen very quickly. Which is part of the reason for the abruptness in the graph you mention, and that abruptness also gives physicists confidence that the neutrinos were coming from the superonva and not somewhere else. They did arrive about 3 hours before the visible light. This is explained by the neutrinos being able to escape from the core of a star immediately at the time of core collapse (almost massless, non interacting) whereas the visible light was only emitted when the shockwave from the collapse reached the surface.
1987a is what, 50kpc or so away? If we take the 60ns quicker over 700km (ish) that the paper mentions, then a quick 'back of the envelope' calculation says that the neutrinos should have arrived 4.3 years before the visible light. Unfortunately there were no reliable neutrino detectors around in 1983 (unless the ruskies have some data from Baksan that they never told anyone about). So if there were some special super-luminous neutrinos emitted from 1987a - we missed them
Albert White MSc FRAS
Chairperson, International Dark Sky Association - Irish Section
www.darksky.ie/
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- johnomahony
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- dave_lillis
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Dave L. on facebook , See my images in flickr
Chairman. Shannonside Astronomy Club (Limerick)
Carrying around my 20" obsession is going to kill me,
but what a way to go.
+ 12"LX200, MK67, Meade2045, 4"refractor
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- johnomahony
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