Lead collisions

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Xymox
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Lead collisions

Post by Xymox » Sat Nov 06, 2010 10:11 pm

From the log book
"We are now at the operating energy, 1.38 TeV in each beam ... the highest energy ever for an accelerated lead beam"
Collisions any minute...

wackyvorlon
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Re: Lead collisions

Post by wackyvorlon » Sat Nov 06, 2010 10:28 pm

LHC Page 1 on vistar says they are "preparing for squeeze". What exactly is the squeeze?

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Xymox
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Re: Lead collisions

Post by Xymox » Sun Nov 07, 2010 12:52 am

Collisions have occurred. Looking for pics now...

Celladoor
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Re: Lead collisions

Post by Celladoor » Sun Nov 07, 2010 1:53 am

first heavy ion collisions in CMS, ALICE and ATLAS! not yet with "stable beams" so no tracks seen (tracker switched off) but all going well!

http://twitter.com/CMSexperiment/status ... 1639561216

Stephen
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Re: Lead collisions

Post by Stephen » Sun Nov 07, 2010 5:33 am

I'm glad to see the transition to heavy ions went as smoothly as possible. And more importantly, that we were not eaten by strangelets or vacuum bubbles.

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CharmQuark
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Re: Lead collisions

Post by CharmQuark » Sun Nov 07, 2010 6:04 am

Stephen wrote:I'm glad to see the transition to heavy ions went as smoothly as possible. And more importantly, that we were not eaten by strangelets or vacuum bubbles.
I am just soooooooooooo proud of you for getting though it stephen :clap: well done :Heart:
Anyone who doesn't take truth seriously in small matters cannot be trusted with large ones either by Albert Einstein.

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GrinchQuark
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Re: Lead collisions

Post by GrinchQuark » Sun Nov 07, 2010 7:50 am

Strangelets? I've so much to learn. :shifty:

Kasuha
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Re: Lead collisions

Post by Kasuha » Sun Nov 07, 2010 7:56 am

I wonder how could they have collisions in Atlas and CMS... AFAIK there was just one bunch in each beam and that should collide just in ALICE.
Beam-gas collisions?

Celladoor
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Re: Lead collisions

Post by Celladoor » Sun Nov 07, 2010 8:21 am

Kasuha wrote:AFAIK there was just one bunch in each beam..
No, there was two bunches in each beam.
http://lhc-commissioning.web.cern.ch/lh ... an2010.htm

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LarryS
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Re: Lead collisions

Post by LarryS » Sun Nov 07, 2010 2:30 pm

Beam 1 has buckets 1 and 13371
Beam 2 has buckets 1 and 22281

Beam 1 Bucket 1 will collide with Beam 2 bucket 1 at IP1 ATLAS and IP5 CMS

Beam 1 bucket 13371 will collide with Beam 2 bucket 22281 at IP2 ALICE because:

22281 - 13371 = 8910 the exact difference between two buckets to collide at IP2

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DCWhitworth
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Re: Lead collisions

Post by DCWhitworth » Mon Nov 08, 2010 8:13 am

Accelerator mode - Ion Physics.

First time I've seen that :D

Fun stuff
DC

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DCWhitworth
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Re: Lead collisions

Post by DCWhitworth » Mon Nov 08, 2010 10:35 am

Whoo, hoo. Stable beams !
DC

The LHC - One ring to rule them all !

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Xymox
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Re: Lead collisions

Post by Xymox » Mon Nov 08, 2010 3:40 pm

El Reg has another awesome story

http://www.theregister.co.uk/2010/11/08 ... omfoolery/

And I have changed the LHCPortal splash screen to a recent CMS lead collision..

Image

godzila
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Re: Lead collisions

Post by godzila » Mon Nov 08, 2010 4:30 pm

Now that's a mess of a collision :)

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CharmQuark
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Re: Lead collisions

Post by CharmQuark » Mon Nov 08, 2010 6:27 pm

Awesome :thumbup:
Anyone who doesn't take truth seriously in small matters cannot be trusted with large ones either by Albert Einstein.

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