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ToSeek
2006-May-14, 11:28 PM
Seabed eye studies the secrets of space (http://observer.guardian.co.uk/uk_news/story/0,,1774482,00.html)


Scientists are finalising plans for a 140m telescope that will sit on the seabed in the deepest part of the Mediterranean - and point downwards.

The aim is to study the universe's most elusive particle, the neutrino, and through that to understand more about the complexity of space and how it develops. Billions of these ghostly entities zip through our planet every second on their journeys across space from distant black holes, galaxies and exploding stars. The seabed telescope will track them as they pass through the Earth.

antoniseb
2006-May-14, 11:30 PM
I've been curious about this project and IceCube as to whether they are similar, and whether they will detect the same kinds of (energy range of) neutrinos, and whether these are the same neutrinos detected by Super-K. Does the salt in the water make a big difference?

trinitree88
2006-May-14, 11:48 PM
They might be better off in the Dead Zone of the Black Sea.1.5 miles of lifeless ocean.:shifty:

Joe87
2006-May-15, 12:38 AM
Something I'm curious about is the statement that the neutrino detector will "point downwards." If it detects light pulses that arises from neutrino interactions, won't those light pulses be emitted equally in all directions, so that the detectors will pick up light from neutrino interactions that result from neutrinos that don't go through the earth?

antoniseb
2006-May-15, 12:48 AM
That was a curious thing to me too. I understand how the Amanda project points downward, but not IceCube or this new project.

trinitree88
2006-May-17, 06:26 PM
Something I'm curious about is the statement that the neutrino detector will "point downwards." If it detects light pulses that arises from neutrino interactions, won't those light pulses be emitted equally in all directions, so that the detectors will pick up light from neutrino interactions that result from neutrinos that don't go through the earth?

Cherenkov radiation is not emitted spherically when it occurs, rather a cone is projected in the forward direction of the particle that is traveling faster-than-light-in-a-given-medium. So if you put photomultiplier tubes with directional hoods on them....as you swing them around, you only pick up photons coming at you from Cherenkov cones that arose out of neutrinos coming at you. It's kind of like putting blinders on a race horse, to keep them from getting skittish. In the ocean, pointing the tubes downward picks up little noise, and almost exclusively interactions from Earth-passage neutrinos from the far side (where's Gary Larson when you need him?)...unless you have ambient bioluminescence. U. Indiana has a nice site on detectors. Ciao. Pete.

Gsquare
2006-May-21, 03:43 AM
Something I'm curious about is the statement that the neutrino detector will "point downwards." If it detects light pulses that arises from neutrino interactions, won't those light pulses be emitted equally in all directions,.....

No, they won't, Joe. Let me add to what Pete said. The detectors pick up Cherenkov radiation from the muons which result from neutrino interactions. The direction of the muon emission is within 1/2 degree of the direction of the original neutrino. There is a 3 dimensional array of detectors. Cherenkov radiation comes off the muons at about a 45 degree angle to the direction of travel; so by timing the signals between each detector one can tell the precise direction of the muon as it passes through the array. At least that's how it works in AMANDA.

See here for some details: http://www.amanda.uci.edu/public_info.html
...under the section on 'How it works'.

G^2

trinitree88
2006-May-28, 11:04 AM
[QUOTE=Gsquare]No, they won't, Joe. Let me add to what Pete said. The detectors pick up Cherenkov radiation from the muons which result from neutrino interactions. The direction of the muon emission is within 1/2 degree of the direction of the original neutrino. There is a 3 dimensional array of detectors. Cherenkov radiation comes off the muons at about a 45 degree angle to the direction of travel; so by timing the signals between each detector one can tell the precise direction of the muon as it passes through the array. At least that's how it works in AMANDA.

See here for some details: http://www.amanda.uci.edu/public_info.html
...under the section on 'How it works'.

Edit: My error. They are fine. I learned something valuable today. Pete