Log in

No account? Create an account

Previous Entry | Next Entry

LHC update: beam 1 is circulating!

Within the past few hours, it appears that LHC has been coming back online...

Friday 20th November

22:01 Circulating beam 1... (slight change of plans)

20:38 two turns!

20:24 Beam all the way round to Atlas.

19:55 We'eve got beam 1 around through sectors 23,34,34, and 45 to the collimators to the left of CMS. Took the beam through CMS and then managed a minor quench while steering the beam through sector 56. We're using a single low intensity bunch so the quench is what we call a quenchino and recovery is quick. We hope to back in business in 20 minutes. Image of horizontal trajectory and predicted correction.



(as I post this, it is 22:15 in Geneva (10:15pm), so the last update of "circulating beam 1" was about 15 mintues ago. Presumably, many more updates are coming, so follow the page if you're interested in what happens this time.)

I had heard a few months ago that they were planning to circulate the beams again on my birthday, November 19th. More recently, they said they expected it by this weekend. So today is 1 day late from the previous schedule, but earlier than this weekend (although maybe it will still take through the weekend to get beam 2 going?) For those not following the progress of LHC, they started it up in September 2008, then a few weeks later had a major disaster that required shutting it down for more than a year to fix. Now it is coming back online, and ready to go! But it will still take a while before they are doing actual experiments. They will need to increase the energy and luminosity in stages, doing double and triple checks that everything is working, before it actually gets to the point where they're in new never-seen-before territory.



( 7 comments — Leave a comment )
Nov. 20th, 2009 11:31 pm (UTC)
Wow... I never thought I'd say this, but the LHC totally needs a twitter feed. Those microupdates are mostly compressible to <140 chars.

And let's keep the damn unlucky events at bay this time. (If the whole nutty theory about the LHC sending particles back in time to prevent its own creation is true, could they use it to influence major events (eg we will turn on the LHC if Obama is not re-elected :-) ))
Nov. 21st, 2009 12:29 am (UTC)
yeah, it seems like they are basically using this webpage like a twitter stream. I wonder if they also have a twitter stream--if they do, I haven't seen it.

Here are two good essays by Sean Carroll on LHC that I'd recommend everyone reading (should have put it in my post):



The first is a good commentary on the theory about LHC influencing past events and keeping itself from turning on. Yes, it's crazy, but perhaps not as crazy as it would seem upon first hearing it, and not as crazy as the whole black hole scare, although it's hard to compare the two as they are very different kinds of craziness.

The second one is a list of probabilities (based on Sean's estimates) for what we might discover with the LHC. Several other physicists have also given estimates in other blogs, most of which are roughly in the same ballpark IIRC. He puts supersymmetry at 60%, which is good because that's the one I have money riding on... although other people have estimated it at only 50% or less.
Nov. 21st, 2009 12:56 am (UTC)
ah, here ya go...
Here's the twitter feed:


Found it from this link, which showed up in my RSS feed just after I made my post...


This just showed up on the original page within the past hour, apparently beams in both directions have now been circulated:

"Midnight - circulating beam 2 - thanks to the RF for hanging around past closing time. For the night we'll go back to single turn mode and give the experiments the promised splash events."
Nov. 21st, 2009 12:57 am (UTC)
Re: ah, here ya go...
So apparently, twitter is not updated as often as their main news page.
(Deleted comment)
Nov. 21st, 2009 06:27 am (UTC)
Oh wow. I feel sorry for schizophrenics.
Nov. 21st, 2009 06:27 am (UTC)
and now for the closed timelike loop...
I liked this link so much, I just decided to go back in time a year and a half to give it to you so that you can later give it to me.


Don't worry though, your memory will be conveniently erased so there will be no paradoxes!
Nov. 26th, 2009 08:09 am (UTC)
Yeah, I've been following this since you posted this link to the "commissioning" site - managed to find some links to where I could start to figure out what they were actually talking about - e.g., http://lhc.web.cern.ch/lhc/LHC-DesignReport.html - this isn't rocket science; I've done rocket science... high-energy proton beam engineering is much more subtle than that!
( 7 comments — Leave a comment )


domino plural

Latest Month

May 2017


Powered by LiveJournal.com
Designed by Lizzy Enger