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▲ _Microft 4 hours ago

He receives the prize for conceiving the IceCube neutrino detector, a cubic-kilometer-sized detecter in the Antarctics.

https://en.wikipedia.org/wiki/IceCube_Neutrino_Observatory

Mechanism is via conversion of neutrinos into charged particles which are then detected via Cherenkov radiation which is produced when a charged particle moves with speeds larger then the speed of light in the medium. (That is only possible because it is less than the speed of light in vacuum which cannot be exceeded.)

This was also discussed recently if you are interested: https://news.ycombinator.com/item?id=49655286

https://en.wikipedia.org/wiki/Cherenkov_radiation

▲walrus01 2 hours ago | parent | next [-]

If anyone was wondering how some of that heavy stuff gets to the south pole to build such a large engineering project, at the farthest possible end of any logistics chain:

https://www.google.com/search?client=firefox-b-d&q=south+pol...

https://en.wikipedia.org/wiki/South_Pole_Traverse

https://octanepress.com/content/south-pole-traverse_antartic...

Significant amounts of things still come in by air cargo at great cost, but a lot also comes the long slow way.

▲brookst an hour ago | parent [-]

I am adopting “Furthest possible end of any logistics chain” as a more refined version of “middle of fucking nowhere”. Thank you.

▲walrus01 an hour ago | parent [-]

It would probably be harder if they wanted to put it, for instance, on the ocean floor at Point Nemo, but for sure the literal south pole is pretty damn expensive on a $ per kg to get stuff sent to. And on an ongoing basis to sustain operations 24x7x365 (it's my understanding it runs almost entirely on diesel fuel and/or Jet-A for a big-ass set of generators).

▲imglorp 33 minutes ago | parent | next [-]

I disagree: anywhere in the ocean is easier logistics than crawler trains over land: ship it there and chuck it overboard. They do that to install oil rigs all the time (but that's more like float it there and sink it). Eg: https://www.wired.com/2014/07/dockwise-vanguard-shipping

▲walrus01 20 minutes ago | parent [-]

Yeah, but now imagine the cost of putting large active electronics 4,000 meters down on the sea floor and keeping it running, and getting the data back off it... The cost of running the drill rig seen in the photos of the icecube detector would be a fraction of that.

▲brookst 34 minutes ago | parent | prev [-]

For sure, there are more difficult places, but I don’t think there is any conceivable place where the supply chain runs through the South Pole on its way. I hope not.

▲jgalt212 an hour ago | parent | prev | next [-]

The Telescope in the Ice was a solid book about this.

https://www.amazon.com/dp/1137280085

▲fooker 3 hours ago | parent | prev | next [-]

> produced when a charged particle moves with speeds larger then the speed of light in the medium.

Thanks, I had no idea this was possible!

https://xkcd.com/1053/

▲pfdietz an hour ago | parent | next [-]

And remember, the "speed of light in the medium" depends on the wavelength of the light. This is why prisms separate light by color.

▲jchallis 18 minutes ago | parent | prev | next [-]

Optical sonic boom.

▲rramadass 43 minutes ago | parent | prev [-]

This is quite nuanced and not as most people assume.

It is the "phase velocity of light in that medium" that is exceeded.

phase velocity of light in a medium = speed of light / refractive index of the medium.

Thus the EM wave is slowed down in a medium and so a charged particle can exceed it producing Cherenkov radiation. This is similar to a sonic boom in atmosphere when speed of sound is exceeded. In both cases the object is traveling faster than the wavefront.

It is only in vacuum that "phase velocity of light" = "group velocity of light" = c (i.e. 300,000 km/sec)

What really is the speed of light in a medium/vacuum, group or phase velocity? - https://physics.stackexchange.com/questions/450377/what-real...

▲tonyhart7 2 hours ago | parent | prev [-]

I read all of that and other resources online and still couldn't understand why the hell we need to build that and especially in south pole antartica

▲joshvm 9 minutes ago | parent | next [-]

Neutrinos need a large detector volume for efficiency because they interact so rarely. You can’t detect them directly so you need a transparent medium to detect their collision byproducts. Good detector mediums are water and ice, and are underground to minimise background light. There are relatively few places you can do this. Mine caverns and under the sea are the most common, but marine detectors are notoriously hard to build. Francis Halzen proposed using ice. At the Pole, the glacial plateau is 2 miles high and the breakthrough was confirming that the ice is in fact highly transparent if you go deep enough.

Why the pole specifically? You could probably build a second IceCube 100 miles away, but how are you going to get that materials there? Pole has a skiway for large aircraft and infrastructure to house a large number of people. The traverse (SPoT) only became operational near the end of construction - the initial holes were drilled in 2005 and almost everything had to be flown in.

Telescope In The Ice does a great job of explaining the history and science behind the experiment.

▲Intermernet 2 hours ago | parent | prev | next [-]

The best science comes from areas that have no obvious use. The original insights into nuclear physics, quantum physics and relativity were all pure thought experiments. They led to the world we live in.

I'm personally very happy that we're still funding science that isn't obviously monetised.

The reason for Antarctica is that it's the only place you find cubic kilometres of stable ice that doesn't drift around.

▲whizzter an hour ago | parent | prev | next [-]

My best guess would be just the remoteness.

1: Ice-mass that isn't contaminated by atomic testing fallout (if the ice has been there since the 40s it's without radioactive waste (faschinating to read about how WW2 wrecks is a prime resource of steel since it's a huge amount of steel without trace amounts of radionucletiods from testing fallout).

2: No current interference (nuclear power, radiowaves,etc) creating possible test uncertainties.

3: I'm sure there are other reasons

The negative naturally is cost, but since the expriment succeeded it will probably be useful for any attempts to send robots or even humanity into space beyond the solar system.

▲mr_mitm 2 hours ago | parent | prev [-]

Where else would you go look for a cubic km of ice?

▲erk__ 2 hours ago | parent [-]

Greenland, though that is probably not much better in any measurable way, when it comes to transport.

▲walrus01 an hour ago | parent | next [-]

Another option that's been popular is to get it as deep underground as possible, hard rock mines with empty areas:

https://en.wikipedia.org/wiki/Sudbury_Neutrino_Observatory

https://en.wikipedia.org/wiki/SNO+

https://en.wikipedia.org/wiki/Super-Kamiokande

There's a weird overlap in engineering and physics disciplines between the hard engineering/business practices of the mining industry, and particle physics.

▲trebligdivad 34 minutes ago | parent [-]

Right, but for those they need to make/move/collect a large amount of transparent material, like heavy water etc for the particles to interact with. But they get that 'for free' with the ice.

▲bananasbandanas 39 minutes ago | parent | prev [-]

Logistics is much easier for Greenland, but the optical properties of the ice are not as good as at the south pole.