7 ms·

Man, so relieved it's just cooling one section that is meant by "major consequences", title made me think of the explosion during commissioning. Looks like it's

Man, so relieved it's just cooling one section that is meant by "major consequences", title made me think of the explosion during commissioning. Looks like it's only sector S78 that needs attention: https://op-webtools.web.cern.ch/vistar/vistars.php?usr=LHC2 https://op-webtools.web.cern.ch/vistar/vistars.php?usr=LHC2 This report is impressively detailed for being put out just two days of the incident, but I guess LHC having world class technical diagnostics teams is not too surprising.

bayindirh 3y ago
When I was visiting CERN, the whole accelerator was in maintenance mode. We have seen a detector (IIRC it was ATLAS) which was disassembled in layers, so we were able to see almost all of it. Our guide explained that whole schedule for maintenance and operation is set in stone and whole schedule is planned almost to hour resolution for the next six months or so. Also it's worth noting that, there is periodic maintenance that needs to be done, and that's also planned in advance. Because of this stringent requirements, "several weeks" of shift is indeed a major problem, and by several I guess they are looking to ~8 weeks, if not more.
- FireBeyond 3y ago
  My uncle, who is not a physicist, but "one smart mf", was one of the heads of the beam instrumentation team at Fermilab, and spent a large part of his career designing, building and maintaining detectors. It utterly blows my mind.
vasco 3y ago
The "major consequences" seem to be for the schedule: > This incident will probably have a great impact on the LHC schedule, with machine operation unlikely to resume for at least several weeks. I also read it instantly in case they had a black hole on their hands, even though I'd expect us all to be dead almost instantly if any real "major consequence" event truly happened in the accelerators.
- 3cats-in-a-coat 3y ago
  You can't create a black hole in LHC. Although sometimes when I read social media I wish they could.
  - cubefox 3y ago
    Even if the tenth digit of pi can't be a six, it still might be a six, namely when you don't know it can't be a six because it is a three. Uncertainty is different from possibility.
    - 3cats-in-a-coat 3y ago
      This is just my personal opinion, but the mechanism that creates particles and black holes is the same. Meaning without throwing incredible mass at it, you won’t make a black hole. You can’t. You’ll make a particle or break apart one. Which is in fact what happens. There are also many natural events that resemble what the LHC does, at even greater energies and much greater mass, and yet no black holes. A black hole is dangerous because it’s a planet worth of mass in compact singularity. If it has no such mass it can’t do anything.
      - jfengel 3y ago
        Putting this on a slightly stronger footing: Black holes don't have to be enormous. We focus on the enormous ones because we know how they form from stars, but there's nothing inherent in black hole math to prevent tiny ones. You can, in theory, create ones from energy, because mass and energy are the same. It's not impossible to create a tiny black hole in a collider. Just not the LHC. It doesn't have anywhere near enough energy, even for the tiniest black hole. And even if there were some unexpected physics that did let a microscopic black hole form, it would instantly vaporize in a burst of Hawking radiation. (The smaller a black hole is, the faster it evaporates.) If somehow all of that were wrong, and the LHC did create a tiny black hole with a lifetime longer than a yoctosecond, it could grow and become a real problem very quickly. But if you're inventing that much physics, you might as well just worry about the appearance of a mega-space-goat that eats the Earth, because it's equivalent levels of guessing.
tux3 3y ago
Vistar is so cool :) Also, here's a public grafana I just found with temperature charts in S78 and a bunch of other cryo data: https://dash.web.cern.ch/d/iDRuWWHGz/sector-78-trend https://dash.web.cern.ch/d/iDRuWWHGz/sector-78-trend Not that I can do anything very interesting with that particular bit of information, but I'm always happy to see open data. We could really use more of that in public science, and CERN is really doing a great job

bayindirh 3y ago

When I was visiting CERN, the whole accelerator was in maintenance mode. We have seen a detector (IIRC it was ATLAS) which was disassembled in layers, so we were able to see almost all of it. Our guide explained that whole schedule for maintenance and operation is set in stone and whole schedule is planned almost to hour resolution for the next six months or so. Also it's worth noting that, there is periodic maintenance that needs to be done, and that's also planned in advance. Because of this stringent requirements, "several weeks" of shift is indeed a major problem, and by several I guess they are looking to ~8 weeks, if not more.

FireBeyond 3y ago
My uncle, who is not a physicist, but "one smart mf", was one of the heads of the beam instrumentation team at Fermilab, and spent a large part of his career designing, building and maintaining detectors. It utterly blows my mind.

vasco 3y ago

The "major consequences" seem to be for the schedule: > This incident will probably have a great impact on the LHC schedule, with machine operation unlikely to resume for at least several weeks. I also read it instantly in case they had a black hole on their hands, even though I'd expect us all to be dead almost instantly if any real "major consequence" event truly happened in the accelerators.

3cats-in-a-coat 3y ago
You can't create a black hole in LHC. Although sometimes when I read social media I wish they could.
- cubefox 3y ago
  Even if the tenth digit of pi can't be a six, it still might be a six, namely when you don't know it can't be a six because it is a three. Uncertainty is different from possibility.
  - 3cats-in-a-coat 3y ago
    This is just my personal opinion, but the mechanism that creates particles and black holes is the same. Meaning without throwing incredible mass at it, you won’t make a black hole. You can’t. You’ll make a particle or break apart one. Which is in fact what happens. There are also many natural events that resemble what the LHC does, at even greater energies and much greater mass, and yet no black holes. A black hole is dangerous because it’s a planet worth of mass in compact singularity. If it has no such mass it can’t do anything.
    - jfengel 3y ago
      Putting this on a slightly stronger footing: Black holes don't have to be enormous. We focus on the enormous ones because we know how they form from stars, but there's nothing inherent in black hole math to prevent tiny ones. You can, in theory, create ones from energy, because mass and energy are the same. It's not impossible to create a tiny black hole in a collider. Just not the LHC. It doesn't have anywhere near enough energy, even for the tiniest black hole. And even if there were some unexpected physics that did let a microscopic black hole form, it would instantly vaporize in a burst of Hawking radiation. (The smaller a black hole is, the faster it evaporates.) If somehow all of that were wrong, and the LHC did create a tiny black hole with a lifetime longer than a yoctosecond, it could grow and become a real problem very quickly. But if you're inventing that much physics, you might as well just worry about the appearance of a mega-space-goat that eats the Earth, because it's equivalent levels of guessing.

tux3 3y ago

Vistar is so cool :) Also, here's a public grafana I just found with temperature charts in S78 and a bunch of other cryo data: https://dash.web.cern.ch/d/iDRuWWHGz/sector-78-trend https://dash.web.cern.ch/d/iDRuWWHGz/sector-78-trend Not that I can do anything very interesting with that particular bit of information, but I'm always happy to see open data. We could really use more of that in public science, and CERN is really doing a great job