LHC First Physics: Press Release & Info

[jal]

The following link gives the press release.
http://press.web.cern.ch/press/lhc-first-physics/

Are there links to the papers that will be published?
Will they come from different centers or from CERN?

Will Physic forums use one thread to gather that info?

jal

 

[dlgoff]

I go here for the news:
http://lhc.web.cern.ch/lhc/News.htm"

 

[jal]

http://web.mit.edu/newsoffice/2010/lhc-results-0205.html
Record-breaking collisions

Initial results from high-energy proton collisions at the Large Hadron Collider offer first glimpse of physics at new energy frontier.

This week, team led by researchers from MIT, CERN and the KFKI Research Institute for Particle and Nuclear Physics in Budapest, Hungary, completed work on the first scientific paper analyzing the results of those collisions. Its findings show that the collisions produced an unexpectedly high number of particles called mesons — a factor that will have to be taken into account when physicists start looking for more rarer particles and for the theorized Higgs boson.

In the new paper, submitted to the Journal of High Energy Physics by CMS, the physicists analyzed the number of particles produced in the aftermath of the high-energy collisions. When protons collide, their energy is predominantly transformed into particles called mesons — specifically, two types of mesons known as pions and kaons.

To their surprise, the researchers that the number of those particles increased faster with collision energy than was predicted by their models, which were based on results of lower-energy collisions.

Taking the new findings into account, the team is now tuning its predictions of how many of those mesons will be found during even higher energy collisions. When those high-energy experiments are conducted, it will be critical to know how many such particles to expect so they can be distinguished from more rare particles.

“If we’re looking for rare particles later on, these mesons will be in the background,” says Roland. “These results show us that our expectations were not completely wrong, but we have to modify things a bit.”

 

[jal]

http://agenda.albanova.se/conferenceDisplay.py?confId=1840
COLLOQUIUM: The startup of the LHC and the very first collisions in the ATLAS detector

Thursday*04*February*2010
from 15:15 to 16:15
at Oscar Klein auditorium

Speaker : Jonas Strandberg (University of Michigan)

The last three months have seen the Large Hadron Collider at CERN deliver its first collisions at 900 GeV, and later breaking the world record for the most energetic man-made collisions ever. I will review the excellent progress of the LHC leading up to the successful startup in November last year and give you the latest news and plans for 2010 and beyond.

With 7 TeV collisions just around the corner, a large new window of opportunity to see physics beyond the Standard Model is opening up. The ATLAS detector has already recorded half a million collision events at 900 GeV which has provided a first look at the detector performance with collision data and has allowed for mass peak reconstructions of several of the lightest hadrons. In anticipation of the high-energy collisions expected this spring I will review the first results coming out of ATLAS during these exciting times, showing that ATLAS is well on its way to take on the search for the Higgs Boson and new physics phenomena such as Supersymmetry.
Streaming video

 

[MotoH]

We are at the stage now where the ability to crank up the intensity and energy of the LHC beams to full power is at hand. We’re like a toddler that just learned to walk: the urge to run is present and exciting, but the probability of banging our head would be high!

It has been decided through many meetings, and with considerations of experts on the front lines, that the highest, safest energy the beams can be run at without major repairs is 3.5 TeV per beam with an instantaneous luminosity of 2*1032/cm2/sec. (The LHC was designed for 7 TeV per beam and an intensity of 1034/cm2/sec.)

More intensity means more proton collisions, and more energy means high probability of interesting collisions. Unfortunately, high intensity and high energy also means high risk of accidents – like the one in Sep 2008.

With that in mind, management decided to balance safety of the machine with the drive to explore and make discoveries. So, the current plan sets a goal of collecting a specific amount of data, 1 fb-1, before shutting down for one or two years starting around the beginning of 2012 for repairs and upgrades.

If nature is hiding secrets in areas we now expect them, then this should provide enough data for discovering some of them, or at least allow ruling out some theories – and all without hurting ourselves.

-Mike

http://blogs.uslhc.us/?p=3651"

 

[Redbelly98]

With 7 TeV collisions just around the corner, ...

According to the following, 7 TeV is at least 3 years away:

http://www.nytimes.com/2010/02/06/science/06collide.html?partner=rss&emc=rss

February 5, 2010

The world’s biggest and most expensive physics experiment will finally rumble into regular operation later this month, but it is going to operate at only half power for the next two years and then shut down for a yearlong repair session, CERN, the European Organization for Nuclear Research, said this week.
.
.
.
CERN’s engineers and scientists decided in a meeting in Chamonix, France, this week to play it safe and operate the collider at only 3.5 trillion electron volts, or TeV, the energy unit of choice in particle physics, for the next 18 to 24 months.

Does anybody know what the new/current problems are, if any?

EDIT: just saw MotoH's post.

 

[MotoH]

According to the following, 7 TeV is at least 3 years away:

http://www.nytimes.com/2010/02/06/science/06collide.html?partner=rss&emc=rss


Does anybody know what the new/current problems are, if any?

EDIT: just saw MotoH's post.

There aren't any problems right now, just a lot of working to get it up and running. I believe beams start at the end of February. When beams do start, check this out: http://meltronx.com/lhclite/index.html" It has a bunch of displays that show how the LHC is running. The display to the top right is the cryogenics, and shows if the cooling units are working, and this is how the 2008 helium leak was discovered by people just watching these.

 

[jal]

Here is a a more intimate look of what was happening

http://lhc-commissioning.web.cern.ch/lhc-commissioning/news/LHC-news.htm
LHC Commissioning 2009*
*
The LHC finished its initial commissioning with beam at 18:00 Wednesday 16th December. Since first beam on Friday 20th November:

Friday November 20th Injection of both beams - rough RF capture *
Saturday November 21st Beam 1 circulating - lifetime 10 hours
Sunday November 22nd Beam 2 circulating - lifetime 3 hours
Monday November 23rd First pilot collisions at 450 GeV
First trial ramp (lost 560 GeV - tunes) tune feedback on 1 beam
Tuesday November 26th Precycle established
Energy matching between SPS & LHC *
Sunday November 29th Ramp to 1.07 TeV and then 1.18 TeV (00:43 Monday) Tune PLL commissioned
Monday 30th November Solenoids on Coupling & orbit compensated
Tuesday 1st - Sunday 6th December Aperture, collimation and beam dump studies continued - protection qualified to a sufficent level at 450 GeV to allow "stable beams" to be declared. *
Sunday 6th 06:55 Stable beams at 450 GeV - 4 on 4 pilot intensities Initial struggle with vertical tune
Tuesday 8th December Ramp 2 on 2 - lost one beam after 3 minutes - but first collisions in Atlas (21:40) at 1.18 TeV No logging - suspect loss due tune swing at end of ramp
Friday 11th December (01:30) Stable beam collisions at 450 GeV with high bunch intensities: 4 x 2 10^10 per beam *
Monday 14th December Ramp 2 on 2 to 1.18 TeV - quiet beams - collisons in all four experiments *
Monday 14th December 16 on 16 at 450 GeV - stable beams *
Wednesday 16th December Ramped 4 on 4 to 1.18 TeV - squeezed to 7 m in IR5 - collisions in all four experiments Step 1: to collision tunes
Step 2: to 9 m
Step 3: to 7 m
Wednesday 16th December 18:00 End of run *A nice record of the 26 days courtesy of CMS's e-commentary team.
Our somewhat fragmented week by week record:
Week 51
Week 50**
Week49 *
Week48 ***
Week47 *

 

[jal]

A nice presentation by Bee.
http://backreaction.blogspot.com/

The LHC Proton Source

 

[jal]

Doing a search of “CMS Collaboration” should bring out a lot of the papers
http://xxx.lanl.gov/find/hep-ex/1/au:+Collaboration_CMS/0/1/0/all/0/1

the latest is
http://xxx.lanl.gov/abs/1002.0621
The data were recorded with the Compact Muon Solenoid (CMS) experiment in December 2009 during two 2-hour periods of the LHC commissioning, demonstrating the readiness of CMS in the early phase of LHC operations. The results at √s = 2.36 TeV represent the highest-energy measurements at a particle collider to date.

AND
there is a discussion/explanation of the paper at Collider Blog
http://muon.wordpress.com/2010/02/04/first-cms-physics-paper/
First CMS Physics Paper!
You might want to look at some of the links, (on the right of his blog). They might prove to be informative, (Experimenter blog).

 

[jal]

http://www.iop.org/EJ/article/0953-2048/23/3/034001/sust10_3_034001.pdf?request-id=dc8a26e2-3798-4c8f-be2c-ffbf55c53610
Superconductivity: its role, its success and its setbacks in the Large Hadron Collider of CERN
Lucio Rossi
CERN, European Organization for Nuclear Research, CH-1211 Geneva 23, Switzerland
Received 7 October 2009
Published 22 February 2010
The results of this 20-year-long enterprise will be discussed together with problems faced during construction and commissioning and their remedies. Particular reference is made to the severe incident which occurred nine days after the spectacular start-up of the machine on 10 September 2008. The status of repair and the plan for the physics programme in 2010 are also presented.