silicon and then we'll probably see a spike in neutrino emissions at Icecube, etc. which should be extremely high. That star probably has less than 24 hours once it starts fusing silicon as its primary fuel source.
I believe it's in the carbon phase right now but could be wrong
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Hm? Does this imply that any RSG about to go supernova in our stellar neighborhood would announce itself in neutrino flux some 24h before the show starts? That would be a wild prospect. Does the current instrumentation lend itself to so fast reaction times?
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Great questions. I've been trying to find out if there is any publicly available raw data for neutrino detection events. When Betelgeuse is about to pop, we should get a few hours advanced notice if we see a spike in neutrinos coming from that general area.
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Can we have direction finding with neutrinos? Probability of interaction is so low that difference of arrival time is surely of no use. Individual events should have directional properties.
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I believe direction can be determined by combining detection events from multiple facilities around the world -- It should at least narrow down what region of the sky the neutrinos came from. I doubt you could pinpoint it to a specific star but maybe the constellation, etc.
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No you can't. That's a misconception of generalizing from electromagnetic sources without actual physical understanding.
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First, brightness is essentially constant even if the neutrinos go throuhg the earth. Average neutrino stops in a lightyear of lead, so earth doesn't affect "brightness". Second, they go at the speed of light, and even if detection rates would grow thousandfold, >>
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>> There would be seconds if not minutes in between. The interval of 0.1s that it takes for light to cross earths diameter is utterly swallowed by that uncertainty
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Neutrinos will hit first not because they beat light, but because neutrinos can escape the core before the light can -- from what I've read, that is usually a couple hours before a supernova would be visible to the eye.
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... you fundamentally misanderstood what I was saying. Direction finding through multiple detectors is (often) based on the fact that signal hits the nearer detector first. But the average span between detections per detectors is so large that which detects first is purely random
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Oh I see -- yeah, I have no idea how many "detection events" happen per second / minute / hour. I'd really like to get access to some raw data to play around with it.
Thanks for clarifying.
The only hope with direction finding is if the momentum of the neutrino is inherited by the resulting photon(s). The events are minute twinkles of light in utter darkness btw. How the neutrino's momentum compares with detection medium particles' thermal momentum is relevant here.
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Doubtless wikipedia would tell that despite neutrino mass being a mystery still. How the weak interaction kinematics play out is beyond me, I'm engineering physicist, not particle- or theoretical one.