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Post by dukwon » Fri Jun 21, 2019 8:38 am

For those unaware, ever since the start of Run 2 there has been an object lying on the bottom of the beam pipe in sector 81. It was detected in aperture scans and nicknamed the "Unidentified Lying Object" (ULO). There was some discussion here when it was first detected: viewtopic.php?f=4&t=1627#p11646

The operators were able to measure the size of the object and even tried "scraping" it with the beam. The hypothesis of it being a lump of frozen gas was ruled out after it failed to disappear after being warmed up. Luckily, a bump around it was sufficient to resume operations without affecting physics so extraction was pushed back to LS2.

Well, it's LS2 now so here it is:
Comparison of the ULO (left) and an undamaged plastic shaving (right)
Last edited by dukwon on Mon Jun 24, 2019 6:58 pm, edited 3 times in total.

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Re: The ULO

Post by DCWhitworth » Fri Jun 21, 2019 9:12 am

Fascinating, thanks for this.

The LHC - One ring to rule them all !

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