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Have two consecutive programmed fills ever been achieved?

Posted: Tue Jun 14, 2011 10:05 pm
by jmc2000
Over the time I've been looking at the LHC performing, I've never seen it once manage two programmed fills in succession since a fault usually dumps the beam anyway.

Has it ever managed two consecutive programmed fills?

What is the current optimum fill time given the current turnaround time?

Re: Have two consecutive programmed fills ever been achieved

Posted: Tue Jun 14, 2011 10:52 pm
by DCWhitworth
The answer to the first is definitely yes.

Re: Have two consecutive programmed fills ever been achieved

Posted: Wed Jun 15, 2011 11:21 am
by jmc2000
DCWhitworth wrote:The answer to the first is definitely yes.
Can you give a date?

I'd be interested in looking at the meeting notes to see what they had to say about this.

Re: Have two consecutive programmed fills ever been achieved

Posted: Wed Jun 15, 2011 11:59 am
by Kasuha
I believe you mean consecutive physics fills ending with programmed dump - because almost all MD fills ended with programmed dump even this year and there were quite a few consecutive ones too.
And of course there were many such ones last year and maybe some this year too. There were also some calculations in one of last year's presentations about how long is an optimum run length to deliver maximum luminosity with cycling delays and beam degradation taken into account. But I don't remember what date was it and also many parameters changed since then so I doubt results from then can be applied today.

Re: Have two consecutive programmed fills ever been achieved

Posted: Wed Jun 15, 2011 12:29 pm
by DCWhitworth
jmc2000 wrote:
DCWhitworth wrote:The answer to the first is definitely yes.
Can you give a date?

I'd be interested in looking at the meeting notes to see what they had to say about this.
Sorry, I don't recall dates but neither to I remember it being especially commented upon.

Re: Have two consecutive programmed fills ever been achieved

Posted: Sat Jun 18, 2011 12:21 am
by Harbles
The Boffins at CERN have anticipated your curiosity and provided a statistics page and an efficiency pie chart showing the time spent in various phases of operation and set up here: http://lhc-statistics.web.cern.ch/LHC-S ... index.html

Re: Have two consecutive programmed fills ever been achieved

Posted: Sun Jun 19, 2011 1:00 am
by tswsl1989
Nice link Harbles, I don't think I've seen that one before

Re: Have two consecutive programmed fills ever been achieved

Posted: Sun Jun 19, 2011 1:50 am
by Harbles
It's fairly new a few months I think. Comes from the Commissioning home page which is a handy source of info. http://lhc-commissioning.web.cern.ch/lhc-commissioning/

Re: Have two consecutive programmed fills ever been achieved

Posted: Tue Jun 28, 2011 1:10 pm
by ferar
Crossing fingers seems that fill #1900 and #1901 will do that. Fill #1900 ended up with Programmed Dump, and #1901 is on its way.

Re: Have two consecutive programmed fills ever been achieved

Posted: Tue Jun 28, 2011 2:10 pm
by DCWhitworth
ferar wrote:Crossing fingers seems that fill #1900 and #1901 will do that. Fill #1900 ended up with Programmed Dump, and #1901 is on its way.
Dumped - two out of two :dance: