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Muons used to test the condition of a road bridge in Estonia

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Re: Muons used to test the condition of a road bridge in Estonia

#31

Post by barrenko »

rdtsc wrote: post #15
thinkingQueen wrote: post #8

Earlier quoted context omitted.

> Security patrol will come and bother you if you hand around the bridge for a few minutes? There’s a land war in Europe. Hundreds of thousands have lost their lives during the past few years. There have been cases of sabotage against the Baltic states as well as the Nordic states. Things are pretty grim there and lurking around basic infrastructure pretty much guarantees a talk with the police.

That's certainly a good reason. Thanks for explaining!

It's a three days ride (at a leisure pace of like 40 km/h) from Crimea to Bruxelles.

Re: Muons used to test the condition of a road bridge in Estonia

#32

Post by lazide »

Cthulhu_ wrote: post #30
lazide wrote: post #20

Earlier quoted context omitted.

At least one was confirmed to indeed be exist - quite fascinating. One day hopefully we can find out if the remaining giant looking open area exists too!

Wouldn't there be other ways to detect voids? Strong X-Rays, penetrating radar, or sound wave / seismic measurements taken from every outside and accessible inside space, combined into a 3d model / visualisation. Or is the stone used that impenetrable? I have no idea about these things.

Those other methods do get used, but are of limited utility because the stone is that impenetrable - and it’s a masonry structure with a significant amount of joints, random small voids, etc.

It really does benefit from something like muon/neutron radiation, where absorption is quite low/penetration quite high, so we can ‘see’ pass the first couple centimeters to meters.

Re: Muons used to test the condition of a road bridge in Estonia

#33

Post by teamonkey »

Muons can be picked up by a standard DSLR. Put the cap on (remove the lens if possible), set it to continually take long exposures of 30s or more, put it in a sealed plastic box with some silica gel packets and put the whole thing in the fridge for a while.

Most of the frames will just show noise from the sensor and electronics (the low temperature minimises that), but occasionally you'll see a bright streak as a muon hits it.

Re: Muons used to test the condition of a road bridge in Estonia

#34

Post by shepmaster »

TheSpiceIsLife wrote: post #28
hugh-avherald wrote: post #27

Earlier quoted context omitted.

Can we have one topic on hackernews that doesn't mention rust?

Carefully and purposefully Oxidising Bridges with Rust.

That is a use of https://en.wikipedia.org/wiki/Weathering_steel, actually!

Re: Muons used to test the condition of a road bridge in Estonia

#35

Post by Timwi »

TheSpiceIsLife wrote: post #29
cameldrv wrote: post #25

Earlier quoted context omitted.

Another one along these lines is antineutrinos. They're created by fission reactions, so a nuclear reactor puts out a lot of them. From what's available in the open literature, this seems like it might be getting close to being practical.

Fission reactors spew neutrinos, no need for anti-

Antineutrinos are produced in nuclear reactors when the radioactive products of nuclear fission undergo beta decay.

Source: https://physics.aps.org/articles/v10/66

Re: Muons used to test the condition of a road bridge in Estonia

#36

Post by agnishom »

teamonkey wrote: post #33

Muons can be picked up by a standard DSLR. Put the cap on (remove the lens if possible), set it to continually take long exposures of 30s or more, put it in a sealed plastic box with some silica gel packets and put the whole thing in the fridge for a while. Most of the frames will just show noise from the sensor and electronics (the low temperature minimises that), but occasionally you'll see a bright streak as a muo…

How do you know it's related to a muon?

Re: Muons used to test the condition of a road bridge in Estonia

#37

Post by kimixa »

agnishom wrote: post #36
teamonkey wrote: post #33

Muons can be picked up by a standard DSLR. Put the cap on (remove the lens if possible), set it to continually take long exposures of 30s or more, put it in a sealed plastic box with some silica gel packets and put the whole thing in the fridge for a while. Most of the frames will just show noise from the sensor and electronics (the low temperature minimises that), but occasionally you'll see a bright streak as a muo…

How do you know it's related to a muon?

I'd think it's pretty much any high-energy ionizing radiation that causes those streaks - probably very few of which are muons. There are "local" sources of ionizing radiation pretty much everywhere.

And if [0] is correct about the approximate muon flux - being that "about one per second passes through a volume the size of a person’s head.", the volume of a the CCD sensor that it would have to interact with is so much smaller (being some 10 microns thick) that I doubt it'll be "Take a few 30s exposures" sort of chance, so much as "Winning the lottery" level chance to actually have a muon pass through the sensor, and interact.

[0] https://home.cern/science/physics/cosmic-rays-particles-oute...

Re: Muons used to test the condition of a road bridge in Estonia

#38

Post by mschuster91 »

thinkingQueen wrote: post #8
rdtsc wrote: post #6

Neutrons can be used for these things as well. The advantage, say from x-rays, is attenuation is not by material density, where all metals will just look dark, but by thermal neutron absorption cross section. So boron might be dark, but metals won't be. Muons are much nicer as you don't have to carry a neutron source around with you. > However, if anyone is now thinking of standing under the bridge to get their body…

> Security patrol will come and bother you if you hand around the bridge for a few minutes? There’s a land war in Europe. Hundreds of thousands have lost their lives during the past few years. There have been cases of sabotage against the Baltic states as well as the Nordic states. Things are pretty grim there and lurking around basic infrastructure pretty much guarantees a talk with the police.

And it's not just Europe either. The US has suffered from multiple attacks on electrical substations [1] as well with unknown perpetrators (the suspicion is white supremacists), and on top of that come rednecks shooting at power lines and god knows what else.

Paranoia surrounding critical infrastructure is skyrocketing at the moment, and I'd say for a bunch of very good reasons.

[1] https://en.wikipedia.org/wiki/Moore_County_substation_attack

Re: Muons used to test the condition of a road bridge in Estonia

#39

Post by theultdev »

mschuster91 wrote: post #38
thinkingQueen wrote: post #8

Earlier quoted context omitted.

> Security patrol will come and bother you if you hand around the bridge for a few minutes? There’s a land war in Europe. Hundreds of thousands have lost their lives during the past few years. There have been cases of sabotage against the Baltic states as well as the Nordic states. Things are pretty grim there and lurking around basic infrastructure pretty much guarantees a talk with the police.

And it's not just Europe either. The US has suffered from multiple attacks on electrical substations [1] as well with unknown perpetrators (the suspicion is white supremacists), and on top of that come rednecks shooting at power lines and god knows what else. Paranoia surrounding critical infrastructure is skyrocketing at the moment, and I'd say for a bunch of very good reasons. [1] https://en.wikipedia.org/wiki/Moor…

the "rednecks" are the ones fixing power lines for you.

your neck may not be red because you get to sit inside while they keep your power on for you.

meanwhile you sit inside writing your hateful, elitist, garbage.

the conspiracy theories related to event you linked are ridiculous.

Re: Muons used to test the condition of a road bridge in Estonia

#40

Post by mschuster91 »

theultdev wrote: post #39
mschuster91 wrote: post #38

Earlier quoted context omitted.

And it's not just Europe either. The US has suffered from multiple attacks on electrical substations [1] as well with unknown perpetrators (the suspicion is white supremacists), and on top of that come rednecks shooting at power lines and god knows what else. Paranoia surrounding critical infrastructure is skyrocketing at the moment, and I'd say for a bunch of very good reasons. [1] https://en.wikipedia.org/wiki/Moor…

the "rednecks" are the ones fixing power lines for you. your neck may not be red because you get to sit inside while they keep your power on for you. meanwhile you sit inside writing your hateful, elitist, garbage. the conspiracy theories related to event you linked are ridiculous.

> your neck may not be red because you get to sit inside while they keep your power on for you.

Before I got into IT I was working in construction for our local telco provider, believe me I have seen shit.

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