Older Events and discussion 3/22/10

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jmayes
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Re: ** Current Events and discussion **

Post by jmayes » Thu Mar 04, 2010 2:24 am

Just found it in the logs, very interesting glitch. Intensity hit 1.2e10!

"At 17.28 the RF went off apparently because the OFF command was received but it is not understood why it was sent. Under investigation by the RF team.
Since we didn.t realized. we tried to inject. and we didn.t see the beam was there because was debunched. We didn.t have the reflex of looking at the BCT. just relay on the RF osciloscope.
So we try a sencond time which translated into an overinjection which was detected by the triggering of the BLM @TDI.
Since we just did some a couple of minutes ago a BLM sanity check. we thought that could be a problem with the thresholds of the BLM. and we tried a third injection. Unfortunatelly we didn.t look at the BCT and we didn.t see we were overinjecting. The people of the BI realized looking at the BSRT image. which is now one of our favourite fixed displays!
Moraleja. look at the BCTs after each injection if you have doubts if the beam is there.
TO BE UNDERSTOOD WHY THE RF WENT OFF."
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oxodoes
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Re: ** Current Events and discussion **

Post by oxodoes » Thu Mar 04, 2010 12:04 pm

as Danny252 already pointed out: thats an intensity graph not energy (a ramp is never that abrupt and there were no ramping attempts yesterday)

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LarryS
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Re: ** Current Events and discussion **

Post by LarryS » Thu Mar 04, 2010 4:15 pm

Current "Cryo Status" page shows Sector 23 in BLUE; I understand the RED and Green but does anyone know what the BLUE might indicate?

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CharmQuark
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Re: ** Current Events and discussion **

Post by CharmQuark » Thu Mar 04, 2010 4:32 pm

I was wondering that myself Larry
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DCWhitworth
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Re: ** Current Events and discussion **

Post by DCWhitworth » Thu Mar 04, 2010 4:43 pm

Some of the data appears to be missing for that sector down the bottom.
DC

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CharmQuark
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Re: ** Current Events and discussion **

Post by CharmQuark » Thu Mar 04, 2010 4:46 pm

DC :D

I have no idea what is going on :crazy: think we are pre cycling now :eh: I will just sit here and smile till someone tells me ;)
Anyone who doesn't take truth seriously in small matters cannot be trusted with large ones either by Albert Einstein.

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Re: ** Current Events and discussion **

Post by Danny252 » Thu Mar 04, 2010 5:05 pm

Blue generally indicates "Status Unknown" - the TED indicators on Page 1 go blue when moving because "when they were only halfway up, they were neither up nor down", as the song goes (oh aren't I witty!)

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CharmQuark
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Re: ** Current Events and discussion **

Post by CharmQuark » Thu Mar 04, 2010 5:07 pm

Thank you Danny :D
Anyone who doesn't take truth seriously in small matters cannot be trusted with large ones either by Albert Einstein.

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jmayes
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Re: ** Current Events and discussion **

Post by jmayes » Thu Mar 04, 2010 10:48 pm

Heads up! 2 beams at 4e9 for over an hour now!!! Finally things are starting to smooth out :) :clap:

"B1 circulation in bucket 1, B2 circulating in bucket 1001"

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jmayes
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Re: ** Current Events and discussion **

Post by jmayes » Fri Mar 05, 2010 12:58 am

Alice is in Physics mode!!! First time this year- things are moving very fast now...

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Re: ** Current Events and discussion **

Post by Stephen » Fri Mar 05, 2010 3:53 pm

Did they found out why one beam has a shorter life span than the other? It might cause some problems down the road.

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Re: ** Current Events and discussion **

Post by Danny252 » Sat Mar 06, 2010 6:38 pm

I remember either a topic or a discussion on chat regarding the effect of the ATLAS/CMS/etc. magnets on the beam.

The 0900 meeting today mentions some small corrections to B2 with regards to the CMS magnet going on - but no noticable change to B1. I'm sure it'll interest whoever I was chatting with about it!

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jmayes
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Re: ** Current Events and discussion **

Post by jmayes » Mon Mar 08, 2010 12:28 am

Wow, just started 2 beams of 1E10!! Hopefully fireworks will follow soon :)

From Page1
"ADT commissioning, B1 & B2 intensity 1E10"

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LarryS
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Re: ** Current Events and discussion **

Post by LarryS » Mon Mar 08, 2010 12:42 am

While an intensity of 1E10 is progress, we need to see a "TRUE" for both the "Stable Beams" flag and "moveable devices allowed in" (such as LHCb VELO). Only then do I suspect that collisions might be close.

From the notes under the "progress" option, it is probably a minimum of a few days.

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jmayes
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Re: ** Current Events and discussion **

Post by jmayes » Mon Mar 08, 2010 1:50 am

Well just had a big hickup :( Lost all comm in S67 and S78, now saying a power cut in point 7 with alarms at level 3.

Hope it's not as bad as it sounds.

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