Communities

Writing
Writing
Codidact Meta
Codidact Meta
The Great Outdoors
The Great Outdoors
Photography & Video
Photography & Video
Scientific Speculation
Scientific Speculation
Cooking
Cooking
Electrical Engineering
Electrical Engineering
Judaism
Judaism
Languages & Linguistics
Languages & Linguistics
Software Development
Software Development
Mathematics
Mathematics
Christianity
Christianity
Code Golf
Code Golf
Music
Music
Physics
Physics
Linux Systems
Linux Systems
Power Users
Power Users
Tabletop RPGs
Tabletop RPGs
Community Proposals
Community Proposals
tag:snake search within a tag
answers:0 unanswered questions
user:xxxx search by author id
score:0.5 posts with 0.5+ score
"snake oil" exact phrase
votes:4 posts with 4+ votes
created:<1w created < 1 week ago
post_type:xxxx type of post
Search help
Notifications
Mark all as read See all your notifications »
Q&A

Post History

81%
+7 −0
Q&A Is it possible to create a beam of non-relativistic neutrinos?

Neutrinos have extremely low masses, and it's quite easy for them to reach high energies and speeds. As such, it almost always makes sense to treat a neutrino as being relativistic. I've been doing...

1 answer  ·  posted 4y ago by HDE 226868‭  ·  last activity 4y ago by dmckee‭

#4: Post edited by user avatar HDE 226868‭ · 2020-06-17T14:24:47Z (over 4 years ago)
  • Neutrinos have extremely low masses, and it's quite easy for them to reach high energies and speeds. As such, it almost always makes sense to treat a neutrino as being relativistic. I've been doing some reading on *non-relativistic* neutrinos, [with kinetic energies of $\lesssim$ 1 meV](https://physics.stackexchange.com/a/267065/56299). These would interact even less with matter than ordinary neutrinos; for example, the threshold for producing inverse beta decay is 1.8 MeV. The only non-relativistic neutrinos currently known to be produced naturally are from the [cosmic neutrino background](https://en.wikipedia.org/wiki/Cosmic_neutrino_background) (C$\nu$B), which is redshifted enough for its neutrinos to have a temperature of $\sim$1.95 K and speeds of only several hundred kilometers per second. Therefore, I'm interested in the possibility of producing non-relativistic neutrinos on Earth. Is it possible?
  • I know that existing neutrino beams produce neutrinos [through pion decay](https://news.fnal.gov/2014/12/how-to-make-a-neutrino-beam/) (see [here[(https://arxiv.org/pdf/1805.01373.pdf) for some general history). Proton-proton collisions produce other baryons, including pions and kaons. The charged pions can be aligned by a magnetic field, producing a beam. The pions then decay into muons and muon neutrinos:
  • $$\pi^-\to\mu^-+\bar\nu_{\mu},\quad\pi^+\to\mu^++\nu_{\mu}$$
  • The muons can be blocked, allowing the muon neutrinos and antineutrinos to continue on to their target.
  • The problem is, these neutrinos have way too much energy, and clearly continue through the Earth unimpeded until they reach a detector. This makes me think that it's not a great idea to try to create non-relativistic neutrinos in a particle accelerator: The beams need to have a lot of energy to ensure a significant number of proton-proton collisions, but this also means that the decay products have a lot of energy. Assuming my logic is correct (and it could be wrong), we would need another way. Is it possible to create some sort of beam of non-relativistic neutrinos on Earth, or, as I'm increasingly of the opinion, is this simply completely impossible?
  • Neutrinos have extremely low masses, and it's quite easy for them to reach high energies and speeds. As such, it almost always makes sense to treat a neutrino as being relativistic. I've been doing some reading on *non-relativistic* neutrinos, [with kinetic energies of $\lesssim$ 1 meV](https://physics.stackexchange.com/a/267065/56299). These would interact even less with matter than ordinary neutrinos; for example, the threshold for producing inverse beta decay is 1.8 MeV. The only non-relativistic neutrinos currently known to be produced naturally are from the [cosmic neutrino background](https://en.wikipedia.org/wiki/Cosmic_neutrino_background) (C$\nu$B), which is redshifted enough for its neutrinos to have a temperature of $\sim$1.95 K and speeds of only several hundred kilometers per second. Therefore, I'm interested in the possibility of producing non-relativistic neutrinos on Earth. Is it possible?
  • I know that existing neutrino beams produce neutrinos [through pion decay](https://news.fnal.gov/2014/12/how-to-make-a-neutrino-beam/) (see [here](https://arxiv.org/pdf/1805.01373.pdf) for some general history). Proton-proton collisions produce other baryons, including pions and kaons. The charged pions can be aligned by a magnetic field, producing a beam. The pions then decay into muons and muon neutrinos:
  • $$\pi^-\to\mu^-+\bar\nu_{\mu},\quad\pi^+\to\mu^++\nu_{\mu}$$
  • The muons can be blocked, allowing the muon neutrinos and antineutrinos to continue on to their target.
  • The problem is, these neutrinos have way too much energy, and clearly continue through the Earth unimpeded until they reach a detector. This makes me think that it's not a great idea to try to create non-relativistic neutrinos in a particle accelerator: The beams need to have a lot of energy to ensure a significant number of proton-proton collisions, but this also means that the decay products have a lot of energy. Assuming my logic is correct (and it could be wrong), we would need another way. Is it possible to create some sort of beam of non-relativistic neutrinos on Earth, or, as I'm increasingly of the opinion, is this simply completely impossible?
#3: Post edited by user avatar HDE 226868‭ · 2020-06-17T14:22:55Z (over 4 years ago)
  • Neutrinos have extremely low masses, and it's quite easy for them to reach high energies and speeds. As such, it almost always makes sense to treat a neutrino as being relativistic. I've been doing some reading on *non-relativistic* neutrinos, [with kinetic energies of $\lesssim$ 1 meV](https://physics.stackexchange.com/a/267065/56299). These would interact even less with matter than ordinary neutrinos; for example, the threshold for producing inverse beta decay is 1.8 MeV. The only non-relativistic neutrinos currently known to be produced naturally are from the [cosmic neutrino background](https://en.wikipedia.org/wiki/Cosmic_neutrino_background) (C$\nu$B), which is redshifted enough for its neutrinos to have a temperature of $\sim$1.95 K and speeds of only several hundred kilometers per second. Therefore, I'm interested in the possibility of producing non-relativistic neutrinos on Earth. Is it possible?
  • I know that existing neutrino beams produce neutrinos [through pion decay](https://news.fnal.gov/2014/12/how-to-make-a-neutrino-beam/) (see [here[(https://arxiv.org/pdf/1805.01373.pdf) for some general history). Proton-proton collisions produce other baryons, including pions and kaons. The charged pions can be aligned by a magnetic field, producing a beam. The pions then decay into muons and muon neutrinos:
  • $$\pi^-\to\mu^-+\bar{\nu},\quad\pi^+\to\mu^++
  • u$$
  • The muons can be blocked, allowing the muon neutrinos and antineutrinos to continue on to their target.
  • The problem is, these neutrinos have way too much energy, and clearly continue through the Earth unimpeded until they reach a detector. This makes me think that it's not a great idea to try to create non-relativistic neutrinos in a particle accelerator: The beams need to have a lot of energy to ensure a significant number of proton-proton collisions, but this also means that the decay products have a lot of energy. Assuming my logic is correct (and it could be wrong), we would need another way. Is it possible to create some sort of beam of non-relativistic neutrinos on Earth, or, as I'm increasingly of the opinion, is this simply completely impossible?
  • Neutrinos have extremely low masses, and it's quite easy for them to reach high energies and speeds. As such, it almost always makes sense to treat a neutrino as being relativistic. I've been doing some reading on *non-relativistic* neutrinos, [with kinetic energies of $\lesssim$ 1 meV](https://physics.stackexchange.com/a/267065/56299). These would interact even less with matter than ordinary neutrinos; for example, the threshold for producing inverse beta decay is 1.8 MeV. The only non-relativistic neutrinos currently known to be produced naturally are from the [cosmic neutrino background](https://en.wikipedia.org/wiki/Cosmic_neutrino_background) (C$\nu$B), which is redshifted enough for its neutrinos to have a temperature of $\sim$1.95 K and speeds of only several hundred kilometers per second. Therefore, I'm interested in the possibility of producing non-relativistic neutrinos on Earth. Is it possible?
  • I know that existing neutrino beams produce neutrinos [through pion decay](https://news.fnal.gov/2014/12/how-to-make-a-neutrino-beam/) (see [here[(https://arxiv.org/pdf/1805.01373.pdf) for some general history). Proton-proton collisions produce other baryons, including pions and kaons. The charged pions can be aligned by a magnetic field, producing a beam. The pions then decay into muons and muon neutrinos:
  • $$\pi^-\to\mu^-+\bar\nu_{\mu},\quad\pi^+\to\mu^++
  • u_{\mu}$$
  • The muons can be blocked, allowing the muon neutrinos and antineutrinos to continue on to their target.
  • The problem is, these neutrinos have way too much energy, and clearly continue through the Earth unimpeded until they reach a detector. This makes me think that it's not a great idea to try to create non-relativistic neutrinos in a particle accelerator: The beams need to have a lot of energy to ensure a significant number of proton-proton collisions, but this also means that the decay products have a lot of energy. Assuming my logic is correct (and it could be wrong), we would need another way. Is it possible to create some sort of beam of non-relativistic neutrinos on Earth, or, as I'm increasingly of the opinion, is this simply completely impossible?
#2: Post edited by user avatar HDE 226868‭ · 2020-06-17T14:22:11Z (over 4 years ago)
  • Neutrinos have extremely low masses, and it's quite easy for them to reach high energies and speeds. As such, it almost always makes sense to treat a neutrino as being relativistic. I've been doing some reading on *non-relativistic* neutrinos, [with kinetic energies of $\lesssim$ 1 meV](https://physics.stackexchange.com/a/267065/56299). These would interact even less with matter than ordinary neutrinos; for example, the threshold for producing inverse beta decay is 1.8 MeV. The only non-relativistic neutrinos currently known to be produced naturally are from the [cosmic neutrino background](https://en.wikipedia.org/wiki/Cosmic_neutrino_background) (C$\nu$B), which is redshifted enough for its neutrinos to have a temperature of $\sim$1.95 K and speeds of only several hundred kilometers per second. Therefore, I'm interested in the possibility of producing non-relativistic neutrinos on Earth. Is it possible?
  • I know that existing neutrino beams produce neutrinos [through pion decay](https://news.fnal.gov/2014/12/how-to-make-a-neutrino-beam/) (see [here[(https://arxiv.org/pdf/1805.01373.pdf) for some general history). Proton-proton collisions produce other baryons, including pions and kaons. The charged pions can be aligned by a magnetic field, producing a beam. The pions then decay into muons and muon neutrinos:
  • $$\pi^-\to\mu^-+\bar{
  • u}_{\mu},\quad\pi^+\to\mu^++
  • u_{\mu}$$
  • The muons can be blocked, allowing the muon neutrinos and antineutrinos to continue on to their target.
  • The problem is, these neutrinos have way too much energy, and clearly continue through the Earth unimpeded until they reach a detector. This makes me think that it's not a great idea to try to create non-relativistic neutrinos in a particle accelerator: The beams need to have a lot of energy to ensure a significant number of proton-proton collisions, but this also means that the decay products have a lot of energy. Assuming my logic is correct (and it could be wrong), we would need another way. Is it possible to create some sort of beam of non-relativistic neutrinos on Earth, or, as I'm increasingly of the opinion, is this simply completely impossible?
  • Neutrinos have extremely low masses, and it's quite easy for them to reach high energies and speeds. As such, it almost always makes sense to treat a neutrino as being relativistic. I've been doing some reading on *non-relativistic* neutrinos, [with kinetic energies of $\lesssim$ 1 meV](https://physics.stackexchange.com/a/267065/56299). These would interact even less with matter than ordinary neutrinos; for example, the threshold for producing inverse beta decay is 1.8 MeV. The only non-relativistic neutrinos currently known to be produced naturally are from the [cosmic neutrino background](https://en.wikipedia.org/wiki/Cosmic_neutrino_background) (C$\nu$B), which is redshifted enough for its neutrinos to have a temperature of $\sim$1.95 K and speeds of only several hundred kilometers per second. Therefore, I'm interested in the possibility of producing non-relativistic neutrinos on Earth. Is it possible?
  • I know that existing neutrino beams produce neutrinos [through pion decay](https://news.fnal.gov/2014/12/how-to-make-a-neutrino-beam/) (see [here[(https://arxiv.org/pdf/1805.01373.pdf) for some general history). Proton-proton collisions produce other baryons, including pions and kaons. The charged pions can be aligned by a magnetic field, producing a beam. The pions then decay into muons and muon neutrinos:
  • $$\pi^-\to\mu^-+\bar{
  • u},\quad\pi^+\to\mu^++
  • u$$
  • The muons can be blocked, allowing the muon neutrinos and antineutrinos to continue on to their target.
  • The problem is, these neutrinos have way too much energy, and clearly continue through the Earth unimpeded until they reach a detector. This makes me think that it's not a great idea to try to create non-relativistic neutrinos in a particle accelerator: The beams need to have a lot of energy to ensure a significant number of proton-proton collisions, but this also means that the decay products have a lot of energy. Assuming my logic is correct (and it could be wrong), we would need another way. Is it possible to create some sort of beam of non-relativistic neutrinos on Earth, or, as I'm increasingly of the opinion, is this simply completely impossible?
#1: Initial revision by user avatar HDE 226868‭ · 2020-06-17T14:20:14Z (over 4 years ago)
Neutrinos have extremely low masses, and it's quite easy for them to reach high energies and speeds. As such, it almost always makes sense to treat a neutrino as being relativistic. I've been doing some reading on *non-relativistic* neutrinos, [with kinetic energies of $\lesssim$ 1 meV](https://physics.stackexchange.com/a/267065/56299). These would interact even less with matter than ordinary neutrinos; for example, the threshold for producing inverse beta decay is 1.8 MeV. The only non-relativistic neutrinos currently known to be produced naturally are from the [cosmic neutrino background](https://en.wikipedia.org/wiki/Cosmic_neutrino_background) (C$\nu$B), which is redshifted enough for its neutrinos to have a temperature of $\sim$1.95 K and speeds of only several hundred kilometers per second. Therefore, I'm interested in the possibility of producing non-relativistic neutrinos on Earth. Is it possible?

I know that existing neutrino beams produce neutrinos [through pion decay](https://news.fnal.gov/2014/12/how-to-make-a-neutrino-beam/) (see [here[(https://arxiv.org/pdf/1805.01373.pdf) for some general history). Proton-proton collisions produce other baryons, including pions and kaons. The charged pions can be aligned by a magnetic field, producing a beam. The pions then decay into muons and muon neutrinos:
$$\pi^-\to\mu^-+\bar{\nu}_{\mu},\quad\pi^+\to\mu^++\nu_{\mu}$$
The muons can be blocked, allowing the muon neutrinos and antineutrinos to continue on to their target.

The problem is, these neutrinos have way too much energy, and clearly continue through the Earth unimpeded until they reach a detector. This makes me think that it's not a great idea to try to create non-relativistic neutrinos in a particle accelerator: The beams need to have a lot of energy to ensure a significant number of proton-proton collisions, but this also means that the decay products have a lot of energy. Assuming my logic is correct (and it could be wrong), we would need another way. Is it possible to create some sort of beam of non-relativistic neutrinos on Earth, or, as I'm increasingly of the opinion, is this simply completely impossible?