SN1987A: Revisiting the Data and the Correlation between Neutrino and Gravitational Detectors

Simplex0
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Topic 193992

SN1987A: Revisiting the Data and the
Correlation between Neutrino and
Gravitational Detectors

http://arxiv.org/PS_cache/arxiv/pdf/0810/0810.3759v1.pdf

The link is taken from this page http://arxiv.org/list/gr-qc/new

Bikeman (Heinz-Bernd Eggenstein)
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SN1987A: Revisiting the Data and the Correlation between Neutrin

Wow! Isn't this quite unexpected that this episode of GW science is resurfacing?

I guess this article will meet with some controversial discussion, as it seems to indicate that a room-temperature resonant bar detector can indeed detect a super nova (by its GW radiation or some other, yet undiscovered mechanism). If so, maybe Joe Weber was right in the first place ???? Maybe resonant mass detectors have a far better GW cross section than everybody thought??? I doubt many people will like to see this discussion being opened again, right?

CU
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tullio
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I have a hard copy of a

I have a hard copy of a newspaper article (Corriere della Sera), dated March 3 1987 from La Thuile (a locality close to the Mont Blanc underground neutrino observatory),in which physicists from Torino and Rome are said to have announced a strong time correlation between the neutrino events observed at the Mont Blanc and the possible GW signal observed by the resonant bar antenna in Rome. From the article posted it seems that neutrino events preceded the optical observations of the supernova by more than four hours and the authors suggest that a supernova collapse may extend for hours instead of a few seconds. Very interesting stuff.
Tullio

Simplex0
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RE: Wow! Isn't this quite

Message 86819 in response to message 86817

Quote:

Wow! Isn't this quite unexpected that this episode of GW science is resurfacing?

I guess this article will meet with some controversial discussion, as it seems to indicate that a room-temperature resonant bar detector can indeed detect a super nova (by its GW radiation or some other, yet undiscovered mechanism). If so, maybe Joe Weber was right in the first place ???? Maybe resonant mass detectors have a far better GW cross section than everybody thought??? I doubt many people will like to see this discussion being opened again, right?

CU
Bikeman

On the other hand scientist should always be open-minded and always ready to revaluate their findings and ready to change their mind. But I guess fundamentalists are to be found every ware ;)

And it states that it is a "Correlation" noting more, right?

tullio
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RE: On the other hand

Message 86820 in response to message 86819

Quote:


On the other hand scientist should always be open-minded and always ready to revaluate their findings and ready to change their mind. But I guess fundamentalists are to be found every ware ;)

And it states that it is a "Correlation" noting more, right?


The authors belong to the Amaldi group in Rome and to the Castagnoli group in Torino. I would take them very seriously, they would not risk their scientific fame on doubtful evidence. I have followed their work since the Sixties, as I have followed Joe Weber's work. Maybe GWs have already been observed via the coincidence method on resonant bar detectors.
Tullio

Bikeman (Heinz-Bernd Eggenstein)
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RE: And it states that it

Message 86821 in response to message 86819

Quote:

And it states that it is a "Correlation" noting more, right?

I guess tghe last sentence of the article sums it up:

Quote:

We remark that the correlations reported here appear as due to a com-
mon cause acting on both the g.w. and the neutrino detectors, so that we
cannot exclude the effect of other causes than g.w. (exotic particles ?).

That's quite a bold a statement in my view. It does not outright claim detection of a gravitational wave but even the idea that there is a common effect acting on a neutrino detector and a room-temperature resonant bar detector separated by a huge distance and coinciding with a supernova is almost as spectacular. There had been some other claims of coincidences (between different GW detector, or beteween GW detector "events" and GRBs) as early as in the 60s , but all of those claims failed to get widespread acceptance in the field. Some of those claims indeed failed under rather embarrassing circumstances, so that the threshold for announcing correlations, candidates and coincidences etc is now quite high as I understand it, just to avoid continuing the history of (what is now seen as) false alarms.

CU
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Simplex0
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I'm sure they are

I'm sure they are Tullio.

My point was that also scientist sometimes are gathered in different groups with there one favorite idea of how things 'really are'. Was not that the case with the Schrödingers - and Heisenberg groups?

tullio
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RE: I'm sure they are

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I'm sure they are Tullio.

My point was that also scientist sometimes are gathered in different groups with there one favorite idea of how things 'really are'. Was not that the case with the Schrödingers - and Heisenberg groups?


Well, quantum mechanics seemed to be divided between wave mechanics (the Schroedinger picture) and matrix mechanics (the Heisenberg picture) until P.A.M. Dirac demonstrated their equivalence with his Hilbert space theory. These were great times. Now we are left with two great theories, relativity and quantum mechanics, without a strong link, despite many attempts. As for the supernova observations, what we would need is another supernova in our Galaxy (the last one was in 1602, if I remember). Both neutrino detectors and GW detectors are much more sensitive than in 1987. Without doubt, all optical telescopes, radio telescopes, infrared, X ray and gamma ray telescopes would monitor the phenomenon. But we cannot repeat it, it is not in our power. Cheers.
Tullio

Bikeman (Heinz-Bernd Eggenstein)
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...But not toooo close,

...But not toooo close, please :-) .

Bikeman

tullio
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RE: ...But not toooo close,

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...But not toooo close, please :-) .

Bikeman


That is up to God.
Tullio

Chipper Q
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Another interesting aspect

Another interesting aspect about SN1987A mentioned in the article was the apparent duration of the event, possibly lasting for hours instead of seconds. So where the GW waveform for a merger is a 'chirp', then the signal from a supernova might be more like 'squawk-chirp(s)-squwak(s)' ? Are variable stars in a sort of state of longer-duration collapse?

I thought it was also surprising how much of the total energy ended up as neutrinos, probably a good thing for the galactic neighborhood :))

If they could find a chirp in the resonant bar data, that would be pretty convincing!

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