Search found 165 matches
- Wed Feb 23, 2022 12:31 pm
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests + 2021/22 YETS
A version 1.0 of the 2022 schedule is now publicly available https://edms.cern.ch/ui/file/2664630/1. ... e_v1.0.pdf
- Wed Feb 23, 2022 12:21 pm
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests + 2021/22 YETS
All sectors cold, powering tests ongoing. After cavern closure (24th March) Sector 23 needs a new magnet training campaign: ~20 quenches, 2 weeks estimated, then ready for beam injection.
- Wed Feb 02, 2022 2:19 pm
- Forum: ALICE
- Topic: Tonga volcano eruption detected by ALICE DCS
- Replies: 1
- Views: 7019
Tonga volcano eruption detected by ALICE DCS
A nice demonstration of gas-filled particle detectors fulfilling a secondary/unintended function as barometers
https://alice-collaboration.web.cern.ch/node/35254
https://alice-collaboration.web.cern.ch/node/35254
- Tue Feb 01, 2022 7:49 pm
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests + 2021/22 YETS
Here's my cartoon guess of what happened:
Essentially, the finger must have buckled somewhat at low temperature, then at the warm-up in Feb 2019, it was bent even further by the gap closing due to thermal expansion.- Tue Feb 01, 2022 7:48 pm
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests + 2021/22 YETS
Here's a description of RF fingers from the ESRF website To absorb chamber-to-chamber misalignment and thermal expansion, [...], bellows are used to inter-connect a large number of chambers along the ring circumference. These bellows, however, are seen as resonant cavities by the beam hence breaking...
- Tue Feb 01, 2022 1:23 pm
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests + 2021/22 YETS
Since we're (slowly) discussing YETS, I've added it to the topic. I suggest making a new thread "2022 operations" in March
- Tue Feb 01, 2022 1:21 pm
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests
Here is the aforementioned buckled RF finger found in 21L3
- Wed Dec 29, 2021 10:27 pm
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests
Beam test summary in these slides from Evian: https://indico.cern.ch/event/1077835/co ... s/4533367/
- Wed Dec 29, 2021 10:23 pm
- Forum: The Accelerator
- Topic: Evian Workshop 2021
- Replies: 1
- Views: 4270
Evian Workshop 2021
In November there was the "Evian" Workshop (actually held at CERN due to COVID)
Slides available here: https://indico.cern.ch/event/1077835/timetable/
For the impatient, I recommend checking out the summary talk at the end.
Slides available here: https://indico.cern.ch/event/1077835/timetable/
For the impatient, I recommend checking out the summary talk at the end.
- Tue Nov 09, 2021 1:07 pm
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests
The "ULO" has been identified as a buckled RF finger, so sector 23 will be warmed up for an intervention. This delays the restart by several weeks. (However, better to catch it now than then!)
- Tue Nov 02, 2021 1:52 pm
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests
Highlights from the beam tests:
- High machine availability throughout the tests (~90%)
- 40 hours of stable beams over 5 nights (6 hours planned)
- All key instruments working, mostly from day 1
- ULO found at 21L3
- Opportunistic ramp to 3.5 TeV with pilot beams
- Tue Nov 02, 2021 1:14 pm
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests
Aperture scans found a "unidentified lying object" (ULO) at 21L3. A bump of a few mm is sufficient to clear it with no problem.
This mirrors the 2015 post-LS1 commissioning, where a ULO was found at 15R8, which turned out to be a piece of plastic
This mirrors the 2015 post-LS1 commissioning, where a ULO was found at 15R8, which turned out to be a piece of plastic
- Wed Oct 27, 2021 8:08 am
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests
Now stable beams!
- Tue Oct 26, 2021 11:55 am
- Forum: New Users Start Here
- Topic: hi
- Replies: 3
- Views: 6926
Re: hi
Welcome. I did see you pop in to the IRC channel the other day. Be aware that it moves fairly slowly (at the moment dominated by LHC comments) but there are a few human users who pay attention. I recommend using a bouncer or something like IRCCloud to stay connected.
- Tue Oct 26, 2021 11:50 am
- Forum: The Accelerator
- Topic: October 2021 Beam Tests + 2021/22 YETS
- Replies: 34
- Views: 42016
Re: October 2021 Beam Tests
First colliding single bunches at 450 GeV in 'adjust' at all IPs! First stable beams scheduled for tomorrow