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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."
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.
1 billion electron volts = 1.6*10^-10 Joules/particle
1 trillion electron volts = 1.6*10^-7 Joules/particle.
The energy of each individual particle is tiny by comparison with things that most people encounter but there are trillions of them whizzing around the LHC its self and that adds up quickly.
Sigs are too short to say anything truly profound so read the above post instead.
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!
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?
I am surprised that no one pointed this out yet, but eV is a unit of energy; it is the energy of one electron accelerated across one Volt. So the relevant equation here is Power = Energy/Time. Thus the real equation is:
energy (Energy) * flux (# of particles / time)
However, as current is, essentially, a charge flux, the particle flux is:
current (Charge/time) / particle_charge (Charge)
However, you ended up with the right answer because the particle_charge term you neglected is equal to the one you neglected in the energy term (E=charge*Volts) namely the elementary charge. So to write the whole thing out:
energy * current / particle_charge
(elementary_charge * voltage) * current / particle_charge
When particle_charge==elementary_charge:
voltage * current
It's a little pedantic, but it is important to note that eV != V, and also that if they accelerate something other than protons or electrons, then your simplistic calculation would be wrong (through at that point Amps is a somewhat ambiguous/improper measurement and probably wouldn't be given anyway).
> 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
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.