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New Particle Identified At LHC
First time accepted submitter m4ktub writes "A team of researchers working with the ATLAS experiment at the LHC have published an article in arXiv where they describe what is believed to be the first observation of a new particle: the boson Chi-b (3P). Professor Roger Jones, Head of the Lancaster ATLAS group, said 'While people are rightly interested in the Higgs boson, which we believe gives particles their mass and may have started to reveal itself, a lot of the mass of everyday objects comes from the strong interaction we are investigating using the Chi-b.'"
They even have chibi particles now.
Give me Classic Slashdot or give me death!
So is that the chibi form of the Higgs boson?
Will His son particle do for now?
Is it a dot or is it a speck?
This guy explains things pretty well:
http://profmattstrassler.com/
Lo and behold, for I am a sig!
The movie about the particle collider this particle's discovery.
/me ducks
"Chi-b Chi-b, BANG BANG"
Quarks come in several different flavours, and protons and neutrons (i.e. almost all "normal" matter) are made of the two lightest flavours: up and down. The heavier flavours are much rarer, and generally very short-lived (which is why you need to "make" them in such an experiment before you can observe them). Quarks normally group up in 3s; with a proton being two ups and a down, and a neutron being two downs and an up. Another form of quark grouping consists of a quark and an anti-quark of the same flavour, which is what's been observed here. And this is the first time that one of these pairs has been observed that consists of quarks with the beauty flavour. Other flavours of pair have been observed before, but its the fact that this one consists of beauty quarks that makes it "new"
It is if you can get a job as one. And if you find that sort of stuff interesting.
However it could be argued that is is also becoming worse to be a physicist. We need larger and more expensive methods of discovering the next step. The discoveries of old can be done in a normal college lab. With say a million dollars worth of equipment enough for a normal institution to invest in. The new stuff is taking billions of dollars, to find. So discoveries are limited to what large governments are willing to pay for.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Actually this particle is a b anti-b pair(b_bar), and particles consisting of b b_bar have been observed before - what makes this particle different from the others is that the b b_bar are in a different state of excitation (3P) - Just like having hydrogen ( consisting of a proton and an electron) in its ground state (1S) you can have hydrogen in an excited state (2S, 1P, 3S, 2P.. etc..) where the electron is in a higher energy state or orbital. With the strong force a large amount of the mass of most particles is tied up in the field binding the two quarks together, so a quarkonium "atom" in a different excited state can have a vastly different mass than the same "atom" in the ground state. For light quarks (uds) almost all the mass of particles made from these quarks comes from the binding energy of the strong force, a neutron consisting of d u d has a mass of around 1GeV but the mass of each of the light quarks is less than 0.001GeV...(1MeV) - this article really isn't that big news, people routinely find these excitations all the time - the heavy quark excitations are interesting in that the masses of these particles can be predicted relatively easily and can be used to test models of the strong force...
Within quark theory, quark/antiquark annihilation is not defined, as that has not been necessary to explain the phenomena we have observed nor does it lead to any verifiable predictions.
This is total nonsense. Quark/antiquark annihilation is perfectly well-described in standard theory. The answer to the OP's question is that the quark and antiquark do annihilate, which is why all mesons are unstable. But it takes a little bit of time for the annihilation to happen, which gives you the lifetime of the meson.
It's against the rules of acquisition.
Give me Classic Slashdot or give me death!
I wish I was an engineer in the Star Trek universe. 95% of every friggin' technical problem is immediately solved by "rerouting power" somewhere or reversing polarity. The other 5% were fixed by "modulating the frequency".
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
To quote Prof Matt Strassler: "except that instead of an atom built from a proton and an electron and held together by the electric force, this is an “atom” built from a bottom quark and a bottom anti-quark and held together by the strong nuclear force. (A few people still call “bottom quarks” by the name“beauty quarks”, but the name is dying out.) We call this atom “bottom quarkonium”, or sometimes “bottomonium”. And instead of calling the different energy levels of this atom “states” or “orbitals”, we call them “particles.”
The thing is we have the 'graviton' listed as the force carrier, but we have not seen or don't even really know what a graviton would look like, so the Higgs is almost and alternate / parallel description of the mechanism.
Sorry but this is just wrong. The Higgs mechanism has nothing whatsoever do so with gravity and is definitely not just some alternative description of it. For a start it is a scalar field with spin-0 and so cannot create a force because that requires a direction so there is no way at all that the Higgs can possibly explain gravity - although it does explain very clearly why energy and mass are related. I appreciate that you are trying to simplify things down for a more general audience but you went a little off the rails here!
I'm not sure I understand how a 115â"130 GeV/c^2 Higgs boson can give mass to a 0.5 MeV/c^2 electron.
That's because the Higgs boson itself does not give the electron mass it is the Higgs field: the Higgs boson is just a quantized vibration of the Higgs field, like a photon is a vibration of the EM field. If you think about it in terms of the surface of a lake then the Higgs boson is a ripple on the surface. However the water in the lake will produce drag even if there are no ripples e.g. if the object is moving very slowly...but things are a little difference because water waves are classical and do not have quantized energy levels.
The "drag" i.e. mass, comes from the fact that the Higgs field does not have zero value. When writing down the equations to describe this physics you end up with two terms: one describing how a Higgs boson couples to the particle and one describing how the non-zero vacuum Higgs field couples to the particle. Since the vacuum value of the Higgs field is constant, and the field is scalar, this last term looks identical to a mass term so the particle behaves exactly the same as a particle with a mass.
The Higgs boson's mass is simply the minimum amount of energy to make the Higgs field vibrate. This is a quantum oscillator effect and so it depends on the shape of the Higgs potential around the vacuum state i.e. how does the energy density in the Higgs field change as you move the field away from the vacuum groundstate.
if mass is caused by Higgs wouldn't that make gravity dependent on Higgs?
No - think of it this way. The Higgs field explains why mass and energy are interchangeable because it explains the mass of the fundamental particles as a binding energy to the non-zero "constant" Higgs field in the universe. Hence all mass is caused by "binding" energy either to the Higgs field e.g. electrons or between particles e.g. quarks in a proton.
Gravity is a force which couples to a particle's 4-momentum NOT just to its mass. This is something Newtonian gravity gets wrong: gravity will bend light which is massless but which has a non-zero 4-momentum. All the Higgs field does is change that 4-momentum. However if we lived in a universe without a Higgs field, so that the fundamental particles have no mass, the mass-less electron would still feel gravitational forces just like the photon does in ours.