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Particle physicist here! Actually it's pretty easy to generate intense neutrino beams. You just have to accelerate protons and smash them into a lead wall. This

Particle physicist here! Actually it's pretty easy to generate intense neutrino beams. You just have to accelerate protons and smash them into a lead wall. This produces all kinds of particles, including for instance muons. Since muons are charged, you can filter and focus them into a beam using magnets, and then they rapidly decay in flight, producing a beam of neutrinos going in the same direction. As you say, they are quite difficult to detect once produced. This is exactly what the DUNE experiment will be doing. It's a large underground detector in North Dakota that will measure properties of neutrinos produced in a beam at Fermilab near Chicago. The difficulties mentioned in the quote from the article have little to do with neutrinos. 1000 TeV is simply an insanely high energy for any particle beam.

deftnerd 6y ago
> Actually it's pretty easy to generate intense neutrino beams. You just have to accelerate protons and smash them into a lead wall. This produces all kinds of particles, including for instance muons. Since muons are charged, you can filter and focus them into a beam using magnets, and then they rapidly decay in flight, producing a beam of neutrinos going in the same direction. That's pretty fascinating. When the protons hit the lead wall, are there any other "messy" particles created that are problematic? Filtering and focusing the muons might be relatively easy to handle, but what about the other kinds of particles that will be created?
- jjk166 6y ago
  By selecting the energy of the proton beam correctly, you can prevent much besides the muons from being produced. Whatever other particles do show up - if not guided by carefully set up electromagnetic fields - will quickly smash into the walls of the device, generating heat as they scatter and decay. Some of this heat can be used to boil a coolant and regenerate energy, but for the most part it is just an inefficiency. The lead wall and some of the material around it will become radioactive waste as some long lived isotopes are produced, but they could potentially have many years of service life.
protomyth 6y ago
Sanford Underground Research Laboratory is in Lead, South Dakota.
- gpderetta 6y ago
  > Lead I guess it is not a coincidence they are putting a neutrino detector in a place called that way. Am I correct to assume there are old lead mines there? Edit: there are mines, very deep mines, but not Lead mines in fact. And the detector is in one of them.
  - zedpm 6y ago
    Lead is not named for the element lead nor is it pronounced the same. It's pronounced like leader (without the er, of course) and named for a mining term[0]. [0]: https://www.britannica.com/place/Lead-South-Dakota https://www.britannica.com/place/Lead-South-Dakota
    - gpderetta 6y ago
      yes, I did check the wiki page after posting my comment, hence my edit :)
      - protomyth 6y ago
        The fun part is there is actually a Leeds, ND (pronounced the same but spelled different) which is named for a place in England which was a bit common in North Dakota even with the large Nordic immigrations. Of course, anything that the Natives put "Spirit" into got renamed "Devil".
- cshimmin 6y ago
  D'oh you are correct. I'm always getting my Dakotas mixed up. I should have also added that this is not my specialty (I work on the ATLAS experiment at the LHC in Switzerland).
  - 6y ago
CalRobert 6y ago
Thank you for that! I just learned something.
Animats 6y ago
Can you modulate and detect the beam fast enough for this to be useful for transmitting low-latency info for high-frequency trading? That could pay for the experiment if you had a detector near NYC.
- cshimmin 6y ago
  Fascinating idea. The neutrinos travel at effectively the speed of light and can be sent directly through the earth, providing a minimum-distance "line of sight" between any two points on earth. However, the same property that allows the neutrinos to pass through the earth is also the reason they're so hard to detect. You would probably only be able to be able to detect modulation frequencies on the order of weeks or months. The bandwidth would be very low to say the least!
  - lostmyoldone 6y ago
    There are research where they've done short haul (~1km i think) neutrino comms at about 0.1bit/s. Slow but still cool, and yes if you could get high enough bitrate for less money than you could gain in HFT trade, it would probably already exist. Them HFT guys and girls do rather crazy stuff to get their nanosecond advantages.
aaronax 6y ago
Actually the detector will be in Lead, South Dakota (in the Black Hills, somewhat near Mt. Rushmore) according to their website.

deftnerd 6y ago

> Actually it's pretty easy to generate intense neutrino beams. You just have to accelerate protons and smash them into a lead wall. This produces all kinds of particles, including for instance muons. Since muons are charged, you can filter and focus them into a beam using magnets, and then they rapidly decay in flight, producing a beam of neutrinos going in the same direction. That's pretty fascinating. When the protons hit the lead wall, are there any other "messy" particles created that are problematic? Filtering and focusing the muons might be relatively easy to handle, but what about the other kinds of particles that will be created?

jjk166 6y ago
By selecting the energy of the proton beam correctly, you can prevent much besides the muons from being produced. Whatever other particles do show up - if not guided by carefully set up electromagnetic fields - will quickly smash into the walls of the device, generating heat as they scatter and decay. Some of this heat can be used to boil a coolant and regenerate energy, but for the most part it is just an inefficiency. The lead wall and some of the material around it will become radioactive waste as some long lived isotopes are produced, but they could potentially have many years of service life.

protomyth 6y ago

Sanford Underground Research Laboratory is in Lead, South Dakota.

gpderetta 6y ago
> Lead I guess it is not a coincidence they are putting a neutrino detector in a place called that way. Am I correct to assume there are old lead mines there? Edit: there are mines, very deep mines, but not Lead mines in fact. And the detector is in one of them.
- zedpm 6y ago
  Lead is not named for the element lead nor is it pronounced the same. It's pronounced like leader (without the er, of course) and named for a mining term[0]. [0]: https://www.britannica.com/place/Lead-South-Dakota https://www.britannica.com/place/Lead-South-Dakota
  - gpderetta 6y ago
    yes, I did check the wiki page after posting my comment, hence my edit :)
    - protomyth 6y ago
      The fun part is there is actually a Leeds, ND (pronounced the same but spelled different) which is named for a place in England which was a bit common in North Dakota even with the large Nordic immigrations. Of course, anything that the Natives put "Spirit" into got renamed "Devil".
cshimmin 6y ago
D'oh you are correct. I'm always getting my Dakotas mixed up. I should have also added that this is not my specialty (I work on the ATLAS experiment at the LHC in Switzerland).
- 6y ago

CalRobert 6y ago

Thank you for that! I just learned something.

Animats 6y ago

Can you modulate and detect the beam fast enough for this to be useful for transmitting low-latency info for high-frequency trading? That could pay for the experiment if you had a detector near NYC.

cshimmin 6y ago
Fascinating idea. The neutrinos travel at effectively the speed of light and can be sent directly through the earth, providing a minimum-distance "line of sight" between any two points on earth. However, the same property that allows the neutrinos to pass through the earth is also the reason they're so hard to detect. You would probably only be able to be able to detect modulation frequencies on the order of weeks or months. The bandwidth would be very low to say the least!
- lostmyoldone 6y ago
  There are research where they've done short haul (~1km i think) neutrino comms at about 0.1bit/s. Slow but still cool, and yes if you could get high enough bitrate for less money than you could gain in HFT trade, it would probably already exist. Them HFT guys and girls do rather crazy stuff to get their nanosecond advantages.

aaronax 6y ago

Actually the detector will be in Lead, South Dakota (in the Black Hills, somewhat near Mt. Rushmore) according to their website.