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Big Button Day -- LIVE

by someone Wed Sep 10th, 2008 at 02:57:42 AM EST

Welcome to big button day at CERN. The beams are ready and waiting. Impatient protons bunched together before the ride of their life in the greatest particle amusement park happy fun land. (Don't tell them we'll eventually want to smash them together and turn them from matter to energy. They may stop cooperating.)

Turn on time should be 09:30, and I will try to follow events as they occur. And post gratuitous pictures I pull from the CERN system. And pretend that something is actually happening, and that it is not just an amphitheatre filled with spectators.

An amphitheatre that is filling up quite well at the moment. Looks like we get a good turnout. Okay, no pics. Seems other people had the same idea as I and the CERN multimedia server is overloaded. Darn.

Live blogging from the LHC - afew


Update [2008-9-10 3:2:3 by someone]:Now we have a count down timer saying 1 minute 30s? Are they turning it on at 9?? Hmm. Also, network is sloooowwww.

Update [2008-9-10 3:2:3 by someone]:Ah, that was the countdown to show us a propaganda video. Quite nice. Shiny graphics.

Update [2008-9-10 4:33:1 by someone]:After having fixed problems all night long they seem to in fact be ready to start it. The control room is filled with people mingle. And it seems that finally they have decided to start the clockwise beam first. Oh, and soon we will be addressed. I think right now we are listening to the BBC or something?

Update [2008-9-10 4:33:1 by someone]:Yes, it is the project leader. This will take a while as he has to repeat everything in French and English. It seems they will start it up two sectors at a time, before going the whole way around.

Update [2008-9-10 4:33:1 by someone]:And now the director general is speaking. He is the big cheese of CERN, the supreme leader, the unchallengeable autocrat. I think he is concluding that CERN is great.

Update [2008-9-10 4:33:1 by someone]:How long will the start-up take? well, LEP (the previous machine) took 12 hours. They hope for less today. Injection in LHC in 5 minutes. The Big Button is ready!

Update [2008-9-10 4:33:1 by someone]:But I see no button? They didn't actually get a button? Hmmm, we've been betting on how the button would look, and now we find there might not be one? Disaster!

Update [2008-9-10 4:33:1 by someone]:Ahhh! Now we get the human interest part! "How do you think the people in the control room feel?" The BBC reporting...

Update [2008-9-10 4:33:1 by someone]:Hmm, de dum. So, of course we are just waiting here. Nothing is actually happening, but the broadcast we are hearing makes a good job of keeping talking. So I will keep posting. And there will be briefings every hour, so I suppose they will have something to report?

Update [2008-9-10 4:33:1 by someone]:Ready? Ready? Go!

Update [2008-9-10 4:33:1 by someone]:"The tension is so high one could cut it with a knife". Ok, BBC. I'm taking away your cliché rights.

Update [2008-9-10 4:33:1 by someone]:APPLAUSE! The beam just made the first 8th of a turn. Now for the next eights.

Update [2008-9-10 4:33:1 by someone]:All around next? No, just to point three.

Update [2008-9-10 4:33:1 by someone]:3..2..1..BING!

Update [2008-9-10 4:33:1 by someone]:Now we wait again, and then another quarter of the way.

Update [2008-9-10 4:33:1 by someone]:48seconds. I love how they do the suspense over and over again. Smart move.

Update [2008-9-10 4:33:1 by someone]:No beam!??!! Next cycle. 48 seconds...

Update [2008-9-10 4:33:1 by someone]:BING! Half way around now. The crowd goes wild! Go Protons! Now, it should be said that the visual evidence of a passing beam is a round white and grey spot on a black background. And an oscilloscope pulse on another monitor. They should add some better graphics.

Update [2008-9-10 4:33:1 by someone]:Reload suspense. Watch the second screen on the bottom. Ready! In 48 seconds. (The length of a cycle for the ring prior to LHC injection.) Now we will test the beam dump. As in, can we safely kick the beam out of the machine if needed.

Update [2008-9-10 4:33:1 by someone]:READY! BING! Beam was dumped as planned. They will now make some corrections before continuing.

Update [2008-9-10 4:33:1 by someone]:No, the beam did not make it to the dump yet. That would be the next step. Now this beam is low energy and low charge, which is why dumping is not really an issue yet. One can just slam it in to a graphite/concrete block without problem. When the full beam at full energy is in the machine this will no longer be possible. Instead, the beam will be dumped in a special way, where it is 'painted' onto the target. A magnet will spiral it so that it spreads over a large area rather than striking all in one point. This process is very important, since hitting in one spot would simply blow the dump block to pieces, and we would have to do a lengthy and costly access to the tunnel and replacement of the block.

Update [2008-9-10 4:33:1 by someone]:Maybe a full turn next? Time to get ready to drum up that suspense again. All eyes on the monitors.

Update [2008-9-10 4:33:1 by someone]:No, one more eight covered. The oscillations of the beam are too large, so they will try to correct before continuing.

Update [2008-9-10 4:33:1 by someone]:Something just happened. Maybe we made another 8th? That would bring us to 7/8 of a turn, I think.

Update [2008-9-10 4:33:1 by someone]:

This is the beam from synchronization tests a few weeks ago. So, coloured spot on coloured background.

Update [2008-9-10 4:33:1 by someone]:So, we have made 3/4 of the ring. I think they will try to complete it next shot. Next cycle, 48 seconds...

Update [2008-9-10 4:33:1 by someone]:Bang! Smash! 7/8th. The beam just crossed one of the large detectors and are trying to look at the data they get just from the passing beam with no collisions. Oh so very close to have a circulating beam in the whole machine.

Update [2008-9-10 4:33:1 by someone]:Now we are ready, they say. Full lap next. Look at the screen and don't blink. You might miss it! The last block is being lifted, and the whole circle is free. So, soon, circulating beam, and then some surprises according to the LHC boss. Surprises? Sounds ominous...

Update [2008-9-10 4:33:1 by someone]:OKAY! DONE AND FINISHED. THE MACHINE HAS BEEN OFFICIALLY STARTED. Now we do two turns!

Update [2008-9-10 4:33:1 by someone]:So a very fast start-up compared to the LEP. Probably because they learned their lesson. Before beam was ever attempted the checked that the passage trough the beam pipe was in fact unobstructed, by, ..., beer bottles. Which is what they discovered in the LEP pipe when trying to start it up.

Update [2008-9-10 4:33:1 by someone]:Now I go for a coffee. I'll be back to try posting some pictures a bit later.

Update [2008-9-10 9:31:33 by someone]: As the machine is running and all went well, I am sure everyone is asking, what exactly is down there, under ground. And how does it work. So here, a very brief overview of what make up a particle accelerator.

First, we know that an object in motion tends to continue in a straight line unless acted upon by some force. In this case, since we wish to have our particle go around a ring, we need to somehow bend their trajectories. The force delivered to the particles to accomplish this is from a magnet known as a dipole magnet. It creates a vertical, constant magnetic field, and a charged particle moving trough this field will experience a horizontal force. This force is such that the direction of the field, the direction of motion of the particle, and the force are all perpendicular to each other. That is, the field is vertical (up or down), the particle moves forward, but under the influence of a force bending it left or right.


The last magnet being lower into the tunnel. Photo ©CERN

Magnets in the tunnel. (A nice picture where you can see the tunnel bend in the distance) Photo ©CERN

This is a particle accelerator, so we need some way to accelerate those things. This is accomplished by creating a beam consisting of bunches of particles, i.e. packets of tightly packed protons, with space in between. The beam at one point in the ring passes through a Radio Frequency cavity. This is a volume that can be filled with RF, that is an electromagnetic wave such as used for radio and other wireless transmissions. Here, however, the RF is packed in tight, with lots of energy, that is absorbed by the passing beam. Since the RF is an oscillating field, we need to also make sure that the wave moves with the particles, so that at all times in the cavity the electric field point in the direction of motion. Half a period later in the wave, the force from the field would be retarding rather than accelerating.

A cavity with RF and beam. See how the beam bunches travel along with the wave.


An LHC cavity under construction ©CERN

A cavity in the tunnel ©CERN

An ideal particle bunch would have all the particles at exactly the same spot, travelling down the centre of the beam pipe, and with no transverse velocity at all. We are however not so lucky as to be able to create such a bunch. Instead we make something having a Gaussian distribution around the mean, and a slice of a bunch looks a bit like this:

We can imagine that this would be a slice right through the beam as it travels down the tube. It could also be a representation of a bunch where the horizontal axis is the location is the horizontal, transverse plane of the particles, and the vertical axis is a measure of the speed of the particles in this same transverse plane. We have thus a bunch of particles with a transverse speed, and if left to themselves they would just smash into the walls of the beam-pipe after a very short while. Somehow they must be contained.

For this we use a second type of magnet. A so called quadrupole. We arrange four magnets such that right in the centre there is no field at all, and the further out you go, the large is the field. Now, such a magnet will have an inward force in one direction, and an outward in the other. So we arrange these magnets, alternating the direction in which the beam is focused and defocused from one to the next.


Quadropole field, blue lines. Focusing in the horizontal plane, and defocusing in the vertical one. The particle in the centre feels no force.

The particles thus bounce back and forward, oscillating about the centre as the hurl down the tube:

Trajectories of particles in one plane as they travel down a quadrupole lattice. The blue lines mark focusing quads, and the red lines defocusing ones. Initially some particles are rejected as they entered the arrangement with too large vertical offset or speed. I.e. they crossed the black lines I put in to mark the beam pipe. The others can continue within this containment indefinitely, though.


Slice of a quadrupole. Two, actually, one for each beam line in the LHC. The four metallic segments around each pipe give rise to the four magnetic poles. Photo ©CERN


Quads being assembled at CERN. Photo ©CERN
To be continued...

Display:
Impending DOOOOOM.
Run! Hide!
by In Wales (inwales aaat eurotrib.com) on Wed Sep 10th, 2008 at 03:49:01 AM EST
This is too exciting!

Should I start screaming yet?

by In Wales (inwales aaat eurotrib.com) on Wed Sep 10th, 2008 at 04:00:31 AM EST
YES!!!!
by someone (s0me1smail(a)gmail(d)com) on Wed Sep 10th, 2008 at 04:04:48 AM EST
[ Parent ]
AAAAARRRRRRRRGGGGGGGGGGGHHHHH!!!!!!!!
by In Wales (inwales aaat eurotrib.com) on Wed Sep 10th, 2008 at 04:07:33 AM EST
[ Parent ]
Great reporting, go on!!!

I'm disappointed about the lack of button - I expected something black, and round, and ominously designed with disco glitter.

European Tribune - Comments - Big Button Day -- LIVE

since hitting in one spot would simply blow the dump block to pieces, and we would have to do a lengthy and costly access to the tunnel and replacement of the block.

Whoa!

by Nomad on Wed Sep 10th, 2008 at 04:08:55 AM EST
I expected something black, and round, and ominously designed with disco glitter.

shame our on-site reporter hasn't mentioned the glitterball in the control room.

(As for the end of the world doommongering, i'd only worry if cern had a shark tank or pirhanna pool) ;-)

Any idiot can face a crisis - it's day to day living that wears you out.

by ceebs (ceebs (at) eurotrib (dot) com) on Wed Sep 10th, 2008 at 05:23:10 AM EST
[ Parent ]
No no, a big wood and metal relay switch, that is heroically pulled down by a scientist in a long white lab coat, goggles, and wild gray hair.  Preferably there will be a strong breeze, making his coat flutter in the wind.

That's SCIENCE!

by Zwackus on Wed Sep 10th, 2008 at 06:37:43 AM EST
[ Parent ]
The oscillations of the beam are too large

Even the beam is overexcited!

by In Wales (inwales aaat eurotrib.com) on Wed Sep 10th, 2008 at 04:11:41 AM EST
someone, help!!!

There's a little black thing floating round in front of my eyes here, I heard the radio this morning and they said watch out for black holes, is this one or is it a fly?

by afew (afew(a in a circle)eurotrib_dot_com) on Wed Sep 10th, 2008 at 04:14:46 AM EST
PS I'd like to put this on the front page. Can you hold off from updating for three minutes from this timestamp while I do it?
by afew (afew(a in a circle)eurotrib_dot_com) on Wed Sep 10th, 2008 at 04:16:10 AM EST
[ Parent ]
Hope I didn't squidge an update of yours. But check, it might have happened.

BTW, is that the time you're using at CERN, or do you need to put your user prefs on CET?

Alternatively, who knows what time it is and does it matter? (No, forget I said matter).

by afew (afew(a in a circle)eurotrib_dot_com) on Wed Sep 10th, 2008 at 04:25:16 AM EST
[ Parent ]
Oh no, we don't even have full beam and already it's messing up the whole fabric of time-space....

DOOOOOM!!

by In Wales (inwales aaat eurotrib.com) on Wed Sep 10th, 2008 at 04:26:25 AM EST
[ Parent ]
Duh... I just realized it's probably time from the beginning of the operation. But it seems to nearly all get updated together.
by afew (afew(a in a circle)eurotrib_dot_com) on Wed Sep 10th, 2008 at 04:32:08 AM EST
[ Parent ]
No, it's the server time. But I don't know why it puts all the updates but the first two on the same timestamp.
by afew (afew(a in a circle)eurotrib_dot_com) on Wed Sep 10th, 2008 at 04:38:39 AM EST
[ Parent ]
No idea what happened. I am on CET, and the first few updates looked okay. Then they turned strange... Oh no! I think In Wales is correct below. We are messing up the space-time. Or possible it is the large scale release of strangelets?
by someone (s0me1smail(a)gmail(d)com) on Wed Sep 10th, 2008 at 04:32:03 AM EST
[ Parent ]
Strangelets?

You can't go for coffee, we might need saving.

by In Wales (inwales aaat eurotrib.com) on Wed Sep 10th, 2008 at 04:34:59 AM EST
[ Parent ]
Strangelets in the night,
Exchanging glances,
Wondering in the night,
What were the chances...

we'd be running into each other further round the collider...

by afew (afew(a in a circle)eurotrib_dot_com) on Wed Sep 10th, 2008 at 04:41:32 AM EST
[ Parent ]
Or perhaps:

People are strange
When you're a strangelet
Quarks are ugly
When you're down.


The fact is that what we're experiencing right now is a top-down disaster. -Paul Krugman

by dvx (dvx.clt ät gmail dotcom) on Wed Sep 10th, 2008 at 05:24:38 AM EST
[ Parent ]
< holds breath>
by In Wales (inwales aaat eurotrib.com) on Wed Sep 10th, 2008 at 04:25:26 AM EST
You see, this is WHY there are SO FEW physicists in the world.  You get two off these characters like someone together, hopefully one female, one male but with them, who can tell with all the giddy screaming, and they are toooooo damn busy looking for the button (yeah, you know which button I'm talking about) to get the job done.

Physicists, BAH!

Now BIOCHEMISTS!  Get two of THOSE BABIES together!  Look out!

They tried to assimilate me. They failed.

by THE Twank (yatta blah blah @ blah.com) on Wed Sep 10th, 2008 at 06:22:41 AM EST
What can the matter be?
Someone's gone and got locked in CERN's lavatory.
She'll be there from Wednesday to eternity,
Everyone knew she was where?

You can't be me, I'm taken
by Sven Triloqvist on Wed Sep 10th, 2008 at 06:51:56 AM EST
I don't want your pity points metavision!!! I want acknowledgement for a brilliant gestaltian twist on the whole live LHC incident. But no...

You can't be me, I'm taken
by Sven Triloqvist on Wed Sep 10th, 2008 at 04:19:19 PM EST
[ Parent ]
There. Quieten down now.
by In Wales (inwales aaat eurotrib.com) on Thu Sep 11th, 2008 at 08:39:00 AM EST
[ Parent ]
You try to take all your ratings with you, I don't want to carry all that weight.  Now, define gestaltian and brilliant and all that over my head.

Our knowledge has surpassed our wisdom. -Charu Saxena.
by metavision on Thu Sep 11th, 2008 at 07:31:11 PM EST
[ Parent ]
Has someone been swallowed by a black coffee hole?

"Dieu se rit des hommes qui se plaignent des conséquences alors qu'ils en chérissent les causes" Jacques-Bénigne Bossuet
by Melanchthon on Wed Sep 10th, 2008 at 07:15:55 AM EST
Fran? Someone? Anyone?

Oh noes!

Is Switzerland still there?

by ThatBritGuy (thatbritguy (at) googlemail.com) on Wed Sep 10th, 2008 at 07:21:24 AM EST
[ Parent ]
Yup, yup. I'm back. The beam finally made three turns and the machine can be said to have started up.
by someone (s0me1smail(a)gmail(d)com) on Wed Sep 10th, 2008 at 07:31:41 AM EST
[ Parent ]
For us out of the loop, on a serious note (if possible), if ALL goes perfectly, WHAT?  Obama wins?  Dick Cheney gets sucked down a black hole? (Can 1 black hole hold that much shit?)

What IS the point?

They tried to assimilate me. They failed.

by THE Twank (yatta blah blah @ blah.com) on Wed Sep 10th, 2008 at 07:38:44 AM EST
[ Parent ]
a 4 micron event horizon could swallow about 200 kilos - so yes, Cheney and Bush. Though I think we are being a little selfish - it's like sending your picnic rubbish on ahead of you to the picnic site. Do we really want another dimension to suffer them?

You can't be me, I'm taken
by Sven Triloqvist on Wed Sep 10th, 2008 at 08:24:47 AM EST
[ Parent ]
Given the form they would arrive in, YES!!

Exactly HOW do we get this done?!

P.S. How do you know about those other dimensions?

They tried to assimilate me. They failed.

by THE Twank (yatta blah blah @ blah.com) on Wed Sep 10th, 2008 at 08:30:40 AM EST
[ Parent ]
I have no idea

You can't be me, I'm taken
by Sven Triloqvist on Wed Sep 10th, 2008 at 08:39:12 AM EST
[ Parent ]
Very good.  Preferred to the alternative explanation.

They tried to assimilate me. They failed.
by THE Twank (yatta blah blah @ blah.com) on Wed Sep 10th, 2008 at 09:54:29 AM EST
[ Parent ]
No difference really, according to the latest neurological research ;-(

You can't be me, I'm taken
by Sven Triloqvist on Wed Sep 10th, 2008 at 10:04:41 AM EST
[ Parent ]
I thought it was meant to be approaching lightspeed, and quite a while later its still only managed three turns, the black hole must be having quite an effect if the speed of light has become that slow.

Any idiot can face a crisis - it's day to day living that wears you out.
by ceebs (ceebs (at) eurotrib (dot) com) on Wed Sep 10th, 2008 at 08:05:04 AM EST
[ Parent ]
If only there was an event horizon big enough to swallow the Earth. Then we could all be stars.

(One of my oldest Bonk jokes...)

You can't be me, I'm taken

by Sven Triloqvist on Wed Sep 10th, 2008 at 08:27:24 AM EST
[ Parent ]
you feel...different...

my partner thinks it would be a nice way to go, getting sucked into another dimension.

we celebrated last night as maybe our last night, she's a tad more concerned about science screwing up than i tend to be, but then her dad was a nuclear engineer.

mad props for your blow-by-blow account, i felt like i was at the derby.

i keep expecting all the observers to walk out of the hall 2" tall! oops...

'The history of public debt is full of irony. It rarely follows our ideas of order and justice.' Thomas Piketty

by melo (melometa4(at)gmail.com) on Wed Sep 10th, 2008 at 09:47:58 AM EST
[ Parent ]
by Fran (fran at eurotrib dot com) on Wed Sep 10th, 2008 at 08:37:17 AM EST
[ Parent ]
For those who want to know what this is all about, here is the Large Hadron Rap:


by Torres on Wed Sep 10th, 2008 at 07:50:30 AM EST
Now it all makes sense.  All the invested money, time, effort ... so someone would have an excuse to make yet another rap video.  It all makes perfectly good sense now.  Silly me.

They tried to assimilate me. They failed.
by THE Twank (yatta blah blah @ blah.com) on Wed Sep 10th, 2008 at 08:39:15 AM EST
[ Parent ]
Wow, if this isn't a ET-Exclusive! Thank you someone, wish I could follow it live here, but Internet is not part of my work. :-)
by Fran (fran at eurotrib dot com) on Wed Sep 10th, 2008 at 08:36:09 AM EST
Never mind Fran - at least in years to come you'll be able to say that you were there. Relatively.

But - what's this about pancakes?

by ThatBritGuy (thatbritguy (at) googlemail.com) on Wed Sep 10th, 2008 at 09:01:42 AM EST
[ Parent ]
Are you implying that thus god is, in fact, a lemon?

You can't be me, I'm taken
by Sven Triloqvist on Wed Sep 10th, 2008 at 10:06:52 AM EST
[ Parent ]
She's certainly not a jug of maple syrup.
by ThatBritGuy (thatbritguy (at) googlemail.com) on Wed Sep 10th, 2008 at 10:37:46 AM EST
[ Parent ]
It's not certainly anything else either.

That I can see.

by afew (afew(a in a circle)eurotrib_dot_com) on Wed Sep 10th, 2008 at 11:28:23 AM EST
[ Parent ]
Ho hum: still here then.

I drink: therefore I am.

"The future is already here -- it's just not very evenly distributed" William Gibson

by ChrisCook (cojockathotmaildotcom) on Wed Sep 10th, 2008 at 06:27:30 PM EST
Are physicists and engineers soon to know unemployment?  I don't know how things work with CERN and its contractors.

Once I built a railroad,
Made it run, made it race against time.
Once I built a railroad,
Now its done, brother can you spare a dime?

---Jay Gorney/E.Y.Harburg

"It is not necessary to have hope in order to persevere."

by ARGeezer (ARGeezer a in a circle eurotrib daught com) on Wed Sep 10th, 2008 at 11:23:33 PM EST
Physicist mostly start their work now, when the data is coming.
For the engeneers - if there really isn't soemthing to do for them any more at CERN - will be very welcome e.g. in the fusion research. Keeping an ulta-hot plasma alive requires vaquely similar skills than making protons rotate.

Der Amerikaner ist die Orchidee unter den Menschen
Volker Pispers
by Martin (weiser.mensch(at)googlemail.com) on Fri Sep 12th, 2008 at 01:00:57 PM EST
[ Parent ]


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