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LHC Reaches Over One Trillion Electron Volts
The LHC has become the world's highest-energy particle accelerator, weighing in at over one trillion electron volts. "Until now the LHC had been operating at a relatively low energy of 450 billion electron volts. On Sunday, engineers increased the energy of this 'pilot beam,' reaching 1.18 trillion electron volts at 2344 GMT. The previous record of 0.98 trillion electron volts has been held by the Tevatron accelerator since 2001. The LHC is eventually expected to operate at some seven trillion electron volts."
If you, like me, are not accustomed to seeing electron volts in this dumbed down prefix-less format, you'll be grateful to find that I've translated the orders of magnitude in the article into a more conventional form:
1 trillion electron volts = 1 TeV
1 billion electron volts = 1 GeV
GAAH! MY PRINTER IS ON FIRE!!! PUT IT OUT! PUT IT OUT!
7 000 000 000 000 electron volts = 1.12152352 × 10E-6 joules
The beam itself isn't too bad, most of the energy costs are for cooling etc. for the electromagnets
I reject your reality and substitute my own.
I don't see anything in the article that says they'll be waiting another year to test it at higher energies. I do see that they expect to do physics with it "next year" -- i.e. in the calendar year 2010, which is only a month away.
A proton (or other particle) at full speed in the LHC: 7 trillion electron Volts 7.0 * 10 ^9 eV. A 100 watt light bulb burning for one hour: 2.2 * 10 ^24 eV So the light bulb represents 3.1* 10 ^14 (that’s 310,000,000,000,000) times the energy of the particle accelerated in the LHC. 7 trillion eV is really, really small.
http://arstechnica.com/science/news/2009/11/lhc-sets-new-energy-record-full-power-still-year-away.ars
The lowest energy supersymmetric particles are expect to reside in the 1TeV range, which is just barely in the detectable range of the Tevatron and the current LHC operating energy. But, to observe these particles, the LHC would have to stay at that energy for some time—of the order of many months—to generate a statistically significant sample of collisions.
Instead, the plan is to continue to increase the energy until ~3.5TeV is reached. At this energy, it will take considerably less time to generate a statistically significant sample. So, by not taking data now, the LHC staff are really saving themselves some time, as well as widening the net for higher-energy particles.
The value is less in the time dilation you get at such high speeds, but rather the equivalent mass. The particles of interest to these scientists have a characteristic mass, which by E=mc^2, means they also have a certain characteristic energy.
(at relativistic speeds I seem to recall it isn't as simple as E=mc^2, but that's the gist of it).
If a particle is really heavy, a low-energy particle accelerator is highly unlikely (basically never) going to find it. This is, in part, why many of the heaviest fundamental particles weren't discovered until recently - sufficiently energetic particle accelerators didn't exist.
In the case of the Higgs Boson, particle physicists don't exactly know how heavy it is. Based on a variety of previous experiments, they have placed lower (and upper?) bounds on its weight. Because we haven't yet found it in our most powerful accelerators, it stands to reason that it is at least more heavy (i.e., more energetic) than 1-2 TeV. Most, but not all, physicists believe the LHC, at 7 TeV, should be energetic enough to find the Higgs boson - if what we think we know about it and particle physics is all correct.
To create a particle like the Higgs boson, the collision energy needs to at least equal the mass of the particle you're trying to create. The higher energy collisions in the LHC increase the odds of finding the Higgs because of this. THe mass of the Higgs isn't known. However, the more collisions we do at higher energies, the thinner the range of masses the Higgs can be.
Sigs are too short to say anything truly profound so read the above post instead.
That's not true at all. When the LHC broke down the first time it caused a decent amount of damage, boring a deep whole into the surrounding concrete. Also the normal beam can bore a hole through 40 meters of solid copper, and it require a very special grouping of materials to stop used up beams.
7 trillion eV is really, really small.
That's actually eV/particle, so total energy depends on the number of particles at that energy.
Set your phasers on "funky"!
The damage in the breakdown was all caused by the energy stored in the magnets that failed and by the pressure of the vaporizing helium.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Said amount of money being a little less than 1% of what the United States alone spent on its stimulus bill. And the project employs several thousand people.
This space unintentionally left unblank.
You've got to keep in mind that this is the energy PER PARTICLE. For reference, 1 gram of matter has something like 10^23 nucleons.
In particle physics, a trillion electron volts is absolutely HUMONGOUS. It is 500 times the energy you get from neutron-antineutron annihilation.
GAAH! MY PRINTER IS ON FIRE!!! PUT IT OUT! PUT IT OUT!
In the case of the Higgs Boson, particle physicists don't exactly know how heavy it is. Based on a variety of previous experiments, they have placed lower (and upper?) bounds on its weight.
According to wikipedia, if the standard model is correct, there i 95% confidentiality that the lower bound is 170GeV and the upper is 186GeV
Religion is regarded by the common people as true, by the wise as false, and by rulers as useful.
Actually, yes, if the paper is moving fast enough, you could. Of course, that would have to be REALLY REALLY fast - assume a sheet of paper to be roughly 100 grams (.1 kg), and a Grand Marquis wet is about 2000kg, the paper would have to be going at least 0.999999999c. Then you'd have to do it a bunch of times before 2 Grand Marquis popped out.
Cheaper to just get the dealer incentives and finance it yourself....
www.eFax.com are spammers
Let me correct a statement: when I said "The Higgs is somewhere north of 1TeV", what I meant was "the energies needed to form a Higgs within a reasonable period of time are north of 1TeV" - the actual mass is currently thought to be in the low hundreds of GeV.
If the Higgs were actually 1TeV in mass that would REALLY screw up the Standard Model.
(now, there are some theorized particles in the same family as the Higgs that are thought to be 1TeV or more, but....)
www.eFax.com are spammers
The particle would not see its own time-dilation so to speak, in the particles rest frame it still decays very quickly and the length contraction then allows it to travel further. From the lab frame the particle is time dilated so decays slowly but the lab equipment is not length contracted in that frame so there are no length contraction effects.
Also with particle accelerators it is very much the energy of the collision that matters, as the particles velocity increases pushing it with more energy actually only increases the speed by a very little amount since it can nevery be greater than c, you can however keep increasing the energy of the particle.
haha, are you suggesting that europe pumps over 14bn euro into a machine and then because some people are slightly impatient, they should whack it up to 11 to see what happens?
"hey, we've not done any tests yet, why are you ramping it up to 7Tev?"
"some guy on slashdot's getting impatient."
"some guy on slashdot's getting impatient!? what are we waiting for??"
*disturbing explosion from underground*
"oh. shit."
science will start in january/february. to be honest, what they're finishing up now is calibrating the detectors which is pretty vital -- and even so they've run beams with more energy than any accelerator ever has before. or do you plan to somehow puzzle out the observations by the power of voodoo?
The lower bound on the mass of the Higgs boson (assuming a Standard Model Higgs) is about 114 GeV (from the LEP experiment, which was the previous experiment at CERN). Just because the Tevatron at Fermilab with a total center-of-mass energy of 2 TeV hasn't seen it, does not mean the Higgs is heavier than 2 TeV. It's much more complicated than that. Even though we collide protons at 2 TeV, the actual collision energy is much less typically only a few 100 GeV because only one quark/antiquark from each proton/antiproton actual collide, which carry only a fraction of the total energy. The problem of finding the Higgs at the Tevatron is its tiny production cross section via quark-antiquark annihilation. The Tevatron is most sensitive in the range around 170 GeV. If the Higgs exists, we have very likely already produced quite a few, it's just impossible to find them in the huge amount of background.
The reason the LHC with its higher total energy helps is because at such high proton energies there are a lot of gluons with energies of around 100 GeV inside the proton, i.e. the LHC is essentially a gluon collider. Going from 2 TeV to 14 TeV actually helps quite a lot here. The Higgs production cross section via gluon-gluon fusion is much higher and in addition the LHC also has a higher overall luminosity which is why we expect to find the Higgs at the LHC. However, even at the LHC the backgrounds are large and so it will take probably at least 3 years of running to have enough statistics to find it.
> So I understand that more energy means faster moving protons and anti-protons.
> How does this equivocate to finding, say, the Higgs-Boson more easily?
In the quantum world you have to forget about "particles" in the classical sense. There is no spoon.
Think, instead, of a big bag with a bunch of quantities in it. Reach into the bag and you can pull something out, shouting "electron"! The chance that you'll say "electron" and not "proton" is based on what you put into the bag, you can only get out something that meets the conservation laws. So if you put in 0 charge, you might get a neutron out, or an electron and a positron, both have net charge 0.
Which one of those you get depends on the rest of the things you put in, spin, isospin, color, momentum, etc. Chances are you'll get the set of particles that has the lowest energy and still meets the requirements. However, you'll always have a chance of getting the oddballs even if there is a low-energy solution.
The reason for high energies in accelerators is to fill up the bag. That way you can reach in and pull out a single really big particle instead of the bunch of little ones you put into it. If the Higgs really is in the 115 to 180 GeV range, as currently believed, you're going to need to put in a WHOLE LOT of energy so you have a lot left over. And even then, you're going to have to try a WHOLE LOT of times before you're going to see it. It's all statistics at that point.
> Anyone have recommended reading for me?
Yes, "The Great Design: Particles, Fields, and Creation". A bit low-rent, but does cover the topics.
Maury
I didn't say every religion did it, however if you do want an example of the catholic church going against scientific findings, try the arguments over efficacy of condoms.
I don't think this example works. It's not that Catholic church doesn't believe that condoms work (either in terms of preventing STDs or babies, at least some 90+ percent of the time). It's that Catholic church believes use of contraceptives like condoms is morally wrong—science is silent in the matters of morality, at least generally speaking.
You can very well argue that church's position is not morally correct (at least to the extent that church's position on condoms may have helped spread STDs), but to say that they have the science wrong is, well, incorrect?
It has been doing "science" for quite a while now, my BOINC client crunched some LHC data long ago, the detectors run just fine off natural cosmic rays collisions. Even at partial energies they could find things they are looking for because HE physics is a probabilistic endeavor, it's just more likely for the events to occur at higher average energies and luminosities.
Apocalypse Cancelled, Sorry, No Ticket Refunds
there you go
Apocalypse Cancelled, Sorry, No Ticket Refunds
"You can grab an electric fence designed for cattle and get more of a shock [due to several quintillion electrons travelling through your body]."
I don't get it. Are you somehow under the impression that there is a single particle (or one in each direction) circulating in the LHC with an energy of 1 TeV (or thereabouts)? Or perhaps you think that the the total energy of the LHC beam is 1 TeV?
Neither of these is true. Each particle in this beam has an energy of 1 TeV and there are lots of particles. To go back to the light bulb comparison, the LHC is quite a lot brighter than a lightbulb (in terms of particles per second) and each one of the particles in it's beam is a hell of a lot more energetic than the photons spewed out by that lightbulb.
Let's take a look at your electric fence. The maximum output of an electric fence is apparently limited to 5 Joules.
Compare to the LHC. According to this CERN page, at full power each beam has a total energy of about 362 MJ, and there are two of them. Some illustrative comparisons from the same page:
1) The kinetic energy of a British aircraft carrier going 11.7 knots (or an American supercarrier going 5.6 knots (*2 for both beams)
2) A Subaru + driver going 1712 km/h (*2 for both beams)
3) Both beams together can melt almost one tonne of copper
4) A high speed train going 150 km/h (* 2 for both beams)
5) 77.4 kg of TNT (*2)
So yeah, quite a bit of energy. I'd much rather take the little tingle from an electric fence as opposed to standing in front of a train going 150 km/h or a car going mach 2.
The combination of HUGE amounts of government funding
No. Firstly, the amounts are tiny compared with the spend on many, many other government activities. There is no "huge" government spend, therefore there is no argument possible against a "huge" spend. Next!
with a real lack of credibility when it comes to the science, means that the LHC is another prime candidate for exposing as fraud.
Well, again, the LHC is the ideal device for exposing which of the current theories is worth pursuing, and which is simply, as you suggest, a gravy train.
This is why I am a big fan of the good work being done by the folks over at LHC Defence.
Well, I hope they are a little more open-minded than the tone of your post.
We need a MUCH better idea of the risks involved
You are aware there have already been several such independent exercises, right? What do you still need to know?
(as well as get a better idea of how realistic the research is)
Erm, that's what it's for. Switch it off and you'll never know.
before we allow it to go any further or allow it to receive any more taxpayer funding.
Good one. Remind me which country pulled funding for the SSC?
"... and more and more now there are all kinds of electronic goodies available" -- Pink Floyd 1972
You should read up on the efficacy claims for condoms made by the Catholic church.
Taking the annual failure rate, using it as a single use failure rate, then using that to guess at an annual rate is just the beginning of their lies (yes lies).
The only saving grace is _nobody_ believes them (or even listens to them).
I'd sooner take relationship advice from /. or 4chan!
IIRC you can find a thick vein of Catholic/condom related BS by searching for 'AIDS virus condom pore size'. I'm too lazy to verify my memory.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'