Rare particle decays could indicate presence of new physics
March 30, 2011 | 12:07 pm
Physicists at the LHCb experiment at the Large Hadron Collider recently reported the first observations of a new way that particles called Bs mesons decay into other particles. Studying this particular decay could provide clues as to why the universe is made up of matter rather than antimatter.
Collaboration members stand in front of the LHCb detector.
Equal amounts of matter and antimatter existed in the earliest stages of the universe. But when a matter particle comes in contact with its antimatter counterpart, the two annihilate one another and leave behind pure energy. In principle, all the matter and antimatter in the universe should have annihilated. But matter managed to survive, and scientists are seeking to explain why.
B mesons could hold the answer. Although they don’t exist naturally, they can be created easily in high-energy particle collisions. They contain a bottom antiquark and either an up, down, charm or strange quark. A peculiar trait of some B mesons is that they spontaneously transform into their own antiparticles and back before decaying into new particles. Last year, researchers at Fermilab discovered that certain B mesons decayed into matter particles 1 percent more often than they decayed into antimatter particles, which could account for the imbalance in the universe.
The cause of the imbalance could be the meddling of an unseen, heavier particle, one that physicists have never observed.
“New physics can influence the way B mesons decay,” said LHCb physicist Steve Blusk from Syracuse University. “What we’re trying to do is effectively measure this interference.”
Previous experiments have observed B mesons switching between matter and antimatter with good precision. With higher collision energies and up to 40 times as much data, LHCb could narrow down the uncertainties in existing data and finally explain the mechanism behind the oscillations.
If the culprit is a new particle too massive to be seen at the LHC, it could be observed through its indirect effect on B meson decays. Studying the decays will help scientists understand the forces acting behind the scenes that result in B mesons decaying to matter more than antimatter.
In a paper published this week in Physics Letters B, the LHCb group describes a new decay mode of one particular B meson, Bs (pronounced B-sub-s), which contains a bottom antiquark and a strange quark. After being created in the wake of a proton-proton collision, Bs mesons can decay into a J/psi particle (a charm quark bound to a charm antiquark) and an f0 (a strange quark bound to a strange antiquark). These particles then decay further, leaving trajectories inside the detector for the researchers to observe.
By studying the difference between the way the Bs meson and its antiparticle decay to this
particular final state, the group can measure the interference between new physics and the Standard Model. If these effects are quite large, as earlier data suggests, LHCb researchers could discover new physics in the data recorded this year.
“At the very least, this will establish that the Standard Model is not the end of the road,” Blusk said.
Lauren Rugani
Posted in energy frontier, LHC results |
7 Comments »
March 30th, 2011 at 2:23 pm
In looking at this back and forth transformation in relation to Rip Theory, the energy in one edge of the particle could be transferring to the other edge of the particle for a very short time, and then back again. The force of this oscillation could cause the rip to rip into smaller rips, thus “decaying” into a combination of other particle types. ~ Tom Sullivan ~
March 30th, 2011 at 4:37 pm
My question for theoretical physicists would be as follows.
If string/brane theories and supersymmetry theories and extra-dimensions theories and multiverse speculations continue to come up completely empty-handed experimentally and observationally, at what point will we say that nature has shown us that our major theoretical efforts to explain the heuristic features of the standard model (26-30 key parameters are “put in by hand”, i.e., heuristically) have failed?
Are theoretical physicists willing to confront the possible need to consider radically different theoretical approaches to understanding nature, i.e., paradigms that replace long-held but untested assumptions with new assumptions that lead to increased potential for unification?
Rather than just present a negative assessment of the last 30 years in theoretical physics, I offer something very positive that suggests a new discrete fractal paradigm for the 21st century.
No theory has ever explained the mass of the electron.
But consider the electron as a virtually naked Kerr-Newman singularity using the Einstein-Maxwell equations, i.e., GR+EM.
The electron mass = (j{j+1}/a^2)^1/4 (alpha^2 e^2/G’)^1/2 .
j = spin; a = dimensionless rotation parameter, alpha = fine structure constant, e = electron charge; G’ = “force” coupling constant.
For j = 1/2 and a = 7/12 [i.e., ~ 1/2] ,
M(e) = 0.5131 MeV [agrees with 0.511 MeV at the 99.6% level]
The new paradigm can now explain the mass of the electron, as well as the mass of the proton, the neutron-proton mass difference, and the masses of 9 other major baryons at the 99.7% level.
The new paradigm can also identify what appears to be the unique path to a unification of General Relativity and Quantum Mechanics.
One critical idea is understanding what G’ is and how to obtain it using observations of nature.
Anybody interested? Details available upon request.
RLO
http://www3.amherst.edu/~rloldershaw
Discrete Scale Relativity
April 3rd, 2011 at 12:28 pm
The Venezuelan Luis Cabareda astrophysicist,(lcabaredaf@gmail.com ) has significant answers to these investigations.
April 5th, 2011 at 2:16 am
“Badly behaving quarks could be pointing to a new elementary particle, and the Large Hadron Collider might be able to hunt it down by the end of this year
When a proton and antiproton are smashed together at nearly light-speed inside the Tevatron Particle Collider in Illinois the Top Quarks, the heaviest of six types of quarks and one of the smallest particles in existance, aren’t quite behaving they way the Standard Model of particle physics says they should be.
This is a rather big deal. Now the Large Hadron Collider, the largest particle accelerator in the world, could be mere months away from discovering the new elementary particle that’s been screwing with the quarks.
Teams at the Tevatron first started noticing the quarks flying off in the wrong directions back in 2008, but these tests could have been flukes, or perhaps a problem with the equipment. Scientists are nothing if not cautious, so nearly four years and hundreds of collisions later, scientists are almost ready to say something is definitely wrong. Where the Standard Model says nine percent of top quarks should be flying off in the direction of the proton beam, the actual number is closer to 45 percent.
The possibility of this particle breaking the Standard Model has stirred physicists up into a frenzy of predictions and theories, trying to make sense of the results of the Tevatron tests.” – Could the future changing the results with the quarks because the large hardon collider is getting close to finding the god particle?
Similar to the double split experiment. Once a dectector wants to find photon, light changes from a wave to particle just by being consciouness of it.
As if the universe was aware that the doulbe split experiment was being conducted to show reality is what one would think, and not both possbilities of wave, and particle.
April 8th, 2011 at 7:21 pm
I have been following the LHC as intelligently as I can in the last few years. Within the Last few months, I have found a lack of information regarding news and updates. The main site shows a shutdown from 2009 and currently under construction. There are still beams running daily and this site was the only one I could find with current news. I am hoping somone can respond as to the most reliable location to find updates regarding progress within the LHC. Sincerely, an average Joe
April 12th, 2011 at 10:37 am
Thanks for your comment. Here are a number of websites that will give you regular updates about the LHC:
http://www.uslhc.us/
http://blogs.uslhc.us/
http://twitter.com/cern/
http://www.quantumdiaries.org/author/cern/
Happy reading!
April 14th, 2011 at 6:54 pm
Thank you very much for your reply. Very helpful!