Mystery photos from CERN's history | Hacker News Reader

Mystery photos from CERN's history

cds.cern.ch

51 pointsgioele7 comments

It's kind of confusing, but I take it many of these have already been solved? For example, one picture is subtitled, "We have no sense of scale for this - Is it some kind of pipe?", and clicking on it leads you to a precise description of the pipe's role and a gallery containing an actual scale photo:

https://cds.cern.ch/record/1765880/files/70-3-376.jpg?subfor...

("The grooves allowed circulation of the cooling fluid, in this case helium" - that's some pretty serious cooling)

The BEBC was a giant cryostat, full of liquid hydrogen:

http://en.wikipedia.org/wiki/Big_European_Bubble_Chamber

My guess is that the cooling wasn't for heat related to the power itself (though perhaps), but to act as a sort of "temperature lock" for the entry point of an outside line. If heat can get in through the openings in the cryostat, you risk boiling off the contents. So you surround the line with something colder than liquid hydrogen, and ensure that the line inside the cryostat isn't warmer than the contents.

I just identified https://cds.cern.ch/record/1764794 , let's see if the description gets updated.

What is it?

I'm really not sure what to be more impressed with, the precision engineering, (which really should not be possible with the technologies of the day - I'm thinking specifically of the non-continuous structure on the mystery pipe that neither casting nor latework could achieve); or the quality of the photography overall.

Evern if some of the mysteries of what is on view are not solved, it's a fascinating collection.

That pipe is almost certainly fabricated out of multiple parts. It isn't a turned piece of solid bar. I'd guess it's a (relatively) thin pipe with a thick flange on the end and rings that slide and lock on to the thinner part of the pipe.

The second last photo seems like something from the rolling tapes era? Something to do with old-room size mainframes?

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