LHC portal

To quote from http://lhc-commissioning.web.cern.ch/lhc-commissioning/:

Plan to restart with beam on 21st February 2011 after the Christmas technical stop. It will take around 3 - 4 weeks to restablish collisions for the experiments. This will be followed by a phased intensity increase. The target for 2011 is around 900 nominal intensity bunches.

Looking here: https://espace.cern.ch/be-dep/BEDepartm ... e_v1.0.pdf it looks like 2011 will have the same format as 2010 - proton physics until November, then Ion physics until the winter shutdown

It is said that a few "green sprouts" can indicate that Spring is drawing near ...

See: "Portal / LHC / Cryo Status"

LarryS wrote:It is said that a few "green sprouts" can indicate that Spring is drawing near ...

See: "Portal / LHC / Cryo Status"

I count eight green sprouts !

DCWhitworth wrote:

LarryS wrote:It is said that a few "green sprouts" can indicate that Spring is drawing near ...

See: "Portal / LHC / Cryo Status"

I count eight green sprouts !

Sixteen today

Any one know if they are running at 50ns or 75ns, i couldnt find any mention of that.

looks like 75ns
http://lhc-commissioning.web.cern.ch/lh ... utline.htm

Dave

morgad wrote:looks like 75ns
http://lhc-commissioning.web.cern.ch/lh ... utline.htm

Dave

The plan is I think to get the LHC running at maximum intensity fairly soon. At the Chamonix conference they were saying they could get triple the number of bunches and double the squeeze that they managed in 2010. So I guess they will be pushing in this direction ASAP to increase the amount of data they get, which was a key factor in the decision to run in 2012.

They're baak! LHC circulates first beam of 2011! Congrats! http://twitter.com/#!/lhcstatus/status/ ... 3358078976

On 2/25 LHC news said: ramp and squeeze ( squeeze to 1.5 m in one go)
Is this a major improvement over last year?

It is about a factor of 2 faster than last year when the squeeze was to 3.5m. In addition it goes in one go - last year there was a couple of stops during the squeeze to check things and move the collimators.

The complete squeeze now takes 476 seconds.

In last year's run they stopped at beta* = 3,5m.
In 2009 (with lower intensity and energy) they squeezed to 2m.
Beams (with even more bunches as last year) squeezed to beta* = 1,5m should give us a considerabely higher luminosity.

On Friday on 23:33 they wrote that they scrape the beam with the primary collimaters in order to get more "microphone data". Are they recording the sound of the beam being scraped down?

Best regards

There are microphones attached to some of the collimators.

What is this data used for (measuring some beam parameters)?

Probably to make a new LHC sc-RAP-e

There isn't a specific use for the mike data - its more for interest. If the beam did hit the collimator full on you would hear a noise like a gunshot .

pcatom wrote:Probably to make a new LHC sc-RAP-e

There isn't a specific use for the mike data - its more for interest. If the beam did hit the collimator full on you would hear a noise like a gunshot .

Sound effects here - http://lhc-collimation-project.web.cern ... movies.htm