Glasgow scientists predict mass of new particle

Jan 26, 2010

(PhysOrg.com) -- A team of physicists from the University of Glasgow has predicted the mass of a new particle which would help explain one of the fundamental forces of the universe.

The scientists say the Bc* will have been produced fleetingly in collisions in the Tevatron accelerator in Illinois, USA and at in Switzerland, but has not yet been spotted by experimentalists searching through the debris.

However, a team led by Professor Christine Davies, head of the University's Particle Physics Theory Group in the Department of Physics and Astronomy, and an expert in Quantum Chromodynamics (QCD) theory, used supercomputers to predict the mass of the meson, which might help scientists understand the strong force that dictates the behaviour of particles at the sub-atomic level.

The strong force is one of the four fundamental forces of the universe and is what holds quarks together - the smallest units of matter found to date. It is this force that QCD theory seeks to understand.

The other fundamental forces are:

* - the phenomenon where bodies of mass are attracted to each other,
* Electromagnetic - the attraction that exists between electrically charged particles such as and ,
* Weak - which is involved in some forms of particle decay, most notably nuclear beta decay

Prof Davies said: "Although this meson has not yet been shown to exist, our calculations have allowed us to predict not only its existence but also its mass. Two previous predictions we've made have been shown to be true so we are confident with this one. We predict the mass of the particle to be 6.330 GeV/c2 with an error of 9 MeV/c2. This is 6.75 times the mass of the proton with an error of 1% of the proton's mass. We predict that this particle is heavier than its cousin the Bc (whose mass we predicted five years ago) by 53(7) MeV/c2."

Quarks come in six varieties (or flavours, as they are known) - up, down, charm, strange, top and bottom. Quarks all have color charge, which is similar to electric charge and causes them to feel the strong force and they also all spin. They differ very much in mass, however - up quarks have a mass a few times that of an electron whilst top quarks are nearly as heavy as a lead nucleus.

Quarks are never found in isolation, however, because the strong force is so powerful that it would take an infinite amount of energy to separate them. Instead they are always found together - in pairs (meson) or threes (baryon) - as particles called hadrons. Protons and neutrons, the particles which make up the nuclei of the atoms in the elements on the periodic table, are examples of hadrons.

The Bc* meson comprises a and a charm antiquark in a configuration in which the quark spins are pointing in the same direction.

Understanding how quarks interact as a result of the strong force helps scientists to connect this knowledge to that of the mesons they see in experimental situations.

Prof Davies said: "The HPQCD collaboration specialises in accurate calculations of the properties of the 'particle zoo' of mesons using the theory of the strong force (QCD), and uses these calculations to determine the properties of quarks. The calculations must be done on very powerful computers, because the strong force is so powerful that it leads to very complicated interactions."

The team at Glasgow is currently working on producing predictions based upon incredibly complex calculations for a variety of different types of particles which can then be compared to the results of experiments at CERN's LHC project.

The knowledge can then be used, it is hoped, to expose gaps in the Standard Model of physics, the theory which attempts to explain what the universe is and how it functions.

Explore further: Halting photons could lead to miniature particle accelerators, improved data transmission

More information: Prediction of the Bc* Mass in Full Lattice QCD, link.aps.org/doi/10.1103/PhysRevLett.104.022001

Provided by University of Glasgow

4.7 /5 (21 votes)

Related Stories

Particle oddball surprises physicists

Mar 18, 2009

(PhysOrg.com) -- Scientists of the CDF experiment at the Department of Energy's Fermi National Accelerator Laboratory announced yesterday that they have found evidence of an unexpected particle whose curious ...

Physicists plan quark conference

Apr 13, 2005

Physicists from around the world will gather at Madison's Monona Terrace from Wednesday, April 27 - Sunday, May 1, to explore the world of quarks, subatomic particles that represent the frontier of modern particle physics. The mee ...

New Physics Results from Fermilab

Aug 22, 2004

Scientists from the Department of Energy's Fermi National Accelerator Laboratory are presenting new results from experiments performed at the world's highest-energy particle accelerator during the 32nd International Conference ...

Protons - Everything Revolves Around Spin

Dec 17, 2007

Current understanding of the spin structure of protons has been summarised in a single book for the first time. The book examines attempts to solve one of the greatest puzzles of physics. Models and experiments ...

Recommended for you

User comments : 17

Adjust slider to filter visible comments by rank

Display comments: newest first

baudrunner
2.1 / 5 (11) Jan 26, 2010
I have no problem understanding what the Universe is - it is reality manifest as the fractal expression of the idea, or premonition if you will, which predetermines its existence, that premonition being the idea that anything existing at all, let alone being cognizant of that fact, is so staggeringly awesome and profound that it simply *sighs* into being through its sheer immensity and weight, relative to nothing which is absent of time, space, and matter. Everything just unfolds and falls into place, into the only reasonably stable state that reality represents. It is not permanent, more like an orgasm, and destined to pass in time -- look at the WMAP cold spot to find the center of the Universe, nothwithstanding that there can be no center in nothing for anything to begin, logic tells us otherwise and that just points to the polarized nature of things that makes everything be in the first place -- no reality without paradox. North and south, up and down, in and out, etc. etc.

frajo
4 / 5 (4) Jan 26, 2010
This is PhysOrg, not PoetOrg.
Mr_Man
5 / 5 (4) Jan 26, 2010
No problem with thought experiment posts, but your post is just stream of thought stoner philosophy, nothing backed by facts or logic, just rambling.
mattytheory
3 / 5 (6) Jan 26, 2010
At least baudrunner HAS ideas. And, I am pretty sure an internet forum IS the place to discuss such ideas.

Vote me down if I am wrong.
frajo
2.3 / 5 (3) Jan 26, 2010
At least baudrunner HAS ideas. And, I am pretty sure an internet forum IS this place to discuss such ideas.

Well, I'd like to discuss my ideas about the lack of hexameters in English language. Anyone interested?
jimbo92107
not rated yet Jan 26, 2010
Don't get me started on metric time...ten hours per day just won't do!
Nik_2213
5 / 5 (1) Jan 26, 2010
Given the 'zoo' of particles, I'm impressed by this prediction. Right or wrong, that's Real Science.
deatopmg
1 / 5 (2) Jan 26, 2010
More particles to patch the paradigm together! Doesn't sound like mother nature where: 3 combinations of 4 bases pairs (occasionally 5 or 6) define life as we know it, 3 subatomic particles; electrons, protons, and neutrons define all the stable 90 odd elements that define our physical world, 2 states: 0 & 1 to do all the calculations we do w/ computers, etc, etc.
Could it be that the theory is wrong and needs a makeover to something less contorted based on all the evidence, instead of magical unseeable particles like gluons and quarks and dark matter?
Oh silly me, of course not!
Nik_2213
not rated yet Jan 26, 2010
"2 states: 0 & 1 to do all the calculations we do w/ computers"

Sorry, that's just convenience. Some devices are tri-state-- 1,0 & 'float', some early devices were unashamedly decimal and, IIRC, ternary logic exists. Let's not go via quantum superpositions, as they make my head hurt...
frajo
1 / 5 (1) Jan 26, 2010
and, IIRC, ternary logic exists
Not only logic. The Setun, built in the CCCP, was a ternary computer.
http://en.wikiped...computer
sams
not rated yet Jan 26, 2010
"it is reality manifest as the fractal expression of the idea"

... but can you predict the existence, or can't calculate the mass, of the Bc* based on that. Show full working ...
mattytheory
not rated yet Jan 26, 2010
At least baudrunner HAS ideas. And, I am pretty sure an internet forum IS this place to discuss such ideas.

Well, I'd like to discuss my ideas about the lack of hexameters in English language. Anyone interested?


Ok so start your discussion. I don't know much about the lack of hexameters in the English language but I would be happy to learn and comment. But we'll have to keep it on the d/l, the mods here will delete your comment if it doesnt pertain explicitly to the referenced article.
PinkElephant
5 / 5 (1) Jan 27, 2010
Could it be that the theory is wrong and needs a makeover to something less contorted based on all the evidence, instead of magical unseeable particles like gluons and quarks and dark matter?


Well, they are talking about just the 6 flavors of quark, that compose the entire particle zoo. Seems rather analogous to the genesis of the periodic table to me.

As for visibility, when was the last time you've seen an actual electron, a proton, or a neutron? The only way we can detect them, is through some fancy equipment. In that respect, quarks aren't that different; they just require equipment that's even fancier.
copernicus
Jan 28, 2010
This comment has been removed by a moderator.
frajo
1 / 5 (1) Jan 28, 2010
SJO12345
1 / 5 (1) Jan 31, 2010
Throughout human history from the discovery of fire, to alchemy, through to Newton and Einstein, our pathway to find the ultimate truths about our universe has not been linear. From the start, we have progressed in branches of hypotheses, slowly and methodically finding which branches hold the most promise, and abandoning those that seem to be dead ends.

And often over this history the "science establishment" has focused their energies into a branch that seems to hold promise, only to find that they were pursuing a ghost. Germ theory and Pasteur is a great example of the "science establishment" in denial until there was no longer a logical reason to belittle Pasteur. One branch in the trail is abandoned while a new branch is taken.

I feel the science establishment is once again mired in the muck of an incorrect branch; a road taken decades ago that has turned more muddy with time. The standard model of microscopic "billiard balls" has run its course. I hope the awakening is near.
frajo
3 / 5 (2) Jan 31, 2010
Throughout human history from the discovery of fire, to alchemy, through to Newton and Einstein, our pathway to find the ultimate truths about our universe has not been linear.
We should replace "ultimate truths about" by "best models for".
gwrede
5 / 5 (1) Feb 01, 2010
Quarks are never found in isolation, however, because the strong force is so powerful that it would take an infinite amount of energy to separate them.

What's infinite about this statement is it's sloppiness.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.