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Muon detection of overhead voids


Following on from the discussion on "Detection of caves by seismic analysis", here's a UK company having won an award for their work with Network Rail in detecting overhead voids: blanked off shafts by detection of the muon count rate.



I see there was a previous mention of muons here: https://ukcaving.com/board/index.php?topic=23074.msg291136#msg291136
Chris Densham, who had some interesting ideas about using muons to see what could be seen above his dig

I stumbled across this whilst investigating a headline in New Scientist that the same company had received funding to investigate the use of muons as an alternative to GPS in polar regions.

I don't subscribe anymore, since their reporting became less scientifically rigorous, they sold out to a new owner and put their price up by a ridiculous amount, but I'd be really interested in how they claim to be able to achieve this.


A bit more here:

From the illustration, it seems that they are using the fact that a single cosmic ray hitting the upper atmosphere will trigger the simultaneous emission of many muons, and they are going to somehow correlate the detection of muons at known base stations with detection at an unknown location.

Muons can penetrate rock, so this is interesting in the context of cave surveying. It will, however, require a very accurate clock at the receiver, and it may require real-time communication with the base stations.


New member
has been  used to find voids in pyramides:

Basically, if you get more muons coming from a specific direction it indicates there is less rock in that direction.

Unfortunately it needs the detectors underneath the void
See also this from the 2017 International Congress of Speleology:
and this from an International Planetary Caves Congress in 2015: