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LHC Has First Collisions After Years of Waiting
An anonymous reader writes "Only four days after the first attempt to send a particle beam around the LHC, we have arrived at the point when all four experiments got their first real collisions from the machine. This was met by celebrations and champagne, as people have been waiting years and years for this moment. It is a testament to the engineering of the machine that collisions were reached already, so few days after restarting. The LHC had already demonstrated ca 10h stable beams, and now also stable beams in both directions at the same time. In the coming weeks, we need only wait for increased intensity and the first attempts at acceleration."
The beams aren't squeezed right now, just centered. You have a higher probability of collisions when they're squeezed (which will be coming up shortly). It was very cool to be in the control room when the first collision took place =)
Despite all the hoopla, all they've really done is cross the streams.
Today the LHC circulated two beams simultaneously for the first time, allowing the operators to test the synchronization of the beams and giving the experiments their first chance to look for proton-proton collisions. With just one bunch of particles circulating in each direction, the beams can be made to cross in up to two places in the ring. From early in the afternoon, the beams were made to cross at points 1 and 5, home to the ATLAS and CMS detectors, both of which were on the look out for collisions. Later, beams crossed at points 2 and 8, ALICE and LHCb.
An important step, sure. But low-speed collisions and beam tuning are not what the LHC is designed to do. It's akin to a pitcher throwing a few warmup pitches - he won't be bringing the heat til he's out on the mound, he's just trying to make sure he shoulder is fucking healed after he blew it out in his first opening game.
By the end of the year we should have some real info about the first useful collisions.
Some screenshots at the CERN site show GNOME's 'Clearlooks' window manager theme. At least BSOD will not be a source for further delays.
My other signature is a car
Probably more like this. It's a better film, too.
-=Maggie Leber=-
Nothing is special about 2012.. Or are you still working on the really in-accurate assumptions of the Mayan calendar?
2012 has no relevance to anything.
Do not look at laser with remaining good eye.
But low-speed collisions and beam tuning are not what the LHC is designed to do.
You do realize that even at the injection energy the speed of the protons is 99.99978% of the speed of light in vacuum and at full energy the speed of the protons has only increased to 99.9999991%? The collisions are both equally high speed thanks to relativity: what is interesting is the collision energy.
Scientific research often usually comes down to "what happens when I mix these two things together?" and "poke it with a stick and see what happens." The biggest variation is the type of stick we use.
Only two things are infinite, the universe and human stupidity, and I'm not entirely sure about the universe - Einstein
"Just kick the system and see what it does". Isn't that usually how we start figuring out how stuff works?
In physics, kicking it will tell you what something does.
In compsci, kicking it will tell you what something did.
I prefer rogues to imbeciles because they sometimes take a rest.
LHC@home was used during the construction of the collider to test and validate magnet calibration scenarios - that phase was completed over three years ago. LHC@Home is no longer associated with the LHC *or* CERN (beyond website hosting) and has not provided [BOINC] work units for over two years.
Do you think, if somehow the sun were turned into a black hole, it would suck in the earth?
How about if we turned a pound of bricks, or a pound of feathers into a black hole with the LHC?
What's that? It would still only have the mass of a pound and not have the gravitational pull to suck 'everything' into it, outside of a radius of ~6.71316708 × 10^-28.
This is not the funny you're looking for.
If the sun turned into a black hole, I believe the Earth would become somewhat colder and less comfortable fairly rapidly. That's besides the point, though - the most reassuring argument I've heard for the LHC not turning the Earth into a black hole is that collisions far more energetic occur all the time, when high-velocity cosmic particles collide with our upper atmosphere. If such collisions had any appreciable chance of creating a microscopic black hole, and that black hole had any appreciable chance of then going all super-happy-meal on the Earth, then it would have already happened.
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.