Two new excited states of the Lambda-b beauty particle observed by LHCb

May 17, 2012

In beautiful agreement with the Standard Model, two new excited states of the Λb beauty particle have just been observed by the LHCb Collaboration. Similarly to protons and neutrons, Λb is composed of three quarks. In the Λb’s case, these are up, down and… beauty.

Although discovering new particles is increasingly looking like a routine exercise for the LHC experiments, it is far from being an obvious performance, particularly when the mass of the particles is high. Created in the high-energy proton-proton collisions produced by the LHC, these new excited states of the Λb particle have been found to have a mass of, respectively, 5912 MeV/c2 and 5920 MeV/c2. In other words, they are over five times heavier than the proton or the neutron.

Physicists only declare a discovery when data significantly show the relevant signal. In order to do that, they often have to analyse large samples of data. To obtain its beautiful result, the LHCb Collaboration has analysed the information coming from about 60 million million (6x1013) proton-proton collisions collected during the 2011 data-taking period. In particular, since the excited states only survive for a very short time before decaying, physicists carefully studied the decay products and tracked the whole process back to the decay vertex. The analysis took scientists several months to complete but today they are able to present the discovery with very high statistical significance, namely 4.9 σ for the first excited state and 10.1 for the second one.

Although never observed before, the excited states of the Λb particle were expected to exist according to the , the theory that tells us how quarks combine to build particles and matter. The LHCb result is therefore a new confirmation of the success of the theory itself.


Matter can be formed in different energy states. The most stable one – that is, the one that survives the longest before decaying – is the so-called “ground state”, in which have the lowest possible energy. States with higher energy are called “excited states”. They are still allowed by Nature but they are unstable. The higher the formation (i.e. the mass) the more unstable they are.

Explore further: Fermilab experiment discovers a heavy relative of the neutron

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not rated yet May 17, 2012
The higher the formation energy (i.e. the mass) the more unstable they are.
This usually doesn't apply to the extreme heavy particles formed in colliders. The duality of dense aether model applies here: the heaviest particles have their energy as poorly defined, at the largest objects in the Universe. Only "medium sized/dense" objects are regular, spherical and of well defined mass (neutron stars) or energy (atoms). The presence of higher energetic levels is therefore typical for heavy particles and due their generally low stability these particles usually decay faster, then they can reach their fundamental quantum state.
not rated yet May 17, 2012
new excited states of the b particle have been found to have a mass of, respectively, 5,912 MeV/c2 and 5,920 MeV/c2
The rest mass of these excited states is significantly higher, than the rest mass predicted for ground state of b beauty hyperon (5,620 MeV). Apparently the energy of quark excitation applies here. It's interesting, how close are the values of rest mass of newest particles revealed at colliders. For example, the mass of quarkonium *b3 confirmed at Tevatron recently is 5,945 MeV.
1 / 5 (1) May 17, 2012
In other words, they are over five times heavier than the proton or the neutron.

They are still allowed by Nature but they are unstable. The higher the formation energy (i.e. the mass) the more unstable they are.

It is interesting to note that how and why the new found particles which are heavier than proton, they are unstable? May be these particles are not the real particles, but just the disturbances of vacuum medium (energy) during the collision, which give an understandable explanation - below.

not rated yet May 18, 2012
how and why the new found particles which are heavier than proton, they are unstable

In dense aether model the appearance of observable reality correspond the appearance of the water surface, being observed with its own waves. It means, the more distant the object is from human mass/energy density scale, the more it appears unstable and temporal. They look like complex fluctuation of dense particle gas, which is the less stable, the heavier it is. I just pointed to the fact, all heavy particles revealed at colliders are of similar rest mass and IMO it's just a consequence of the above theorem. It essentially means, it has not a good meaning to continue in collider experiments based on brute force approach - it's indeed good for employment of physicists and companies involved, but we already did hit the limits of the observability of material objects inside of our Universe. The further increasing of energy of collisions will just increase the noise/signal ratio.
not rated yet May 18, 2012
It doesn't mean, we are predestined for not to reveal anything new from this moment, but we should work smarter, not harder, illustratively speaking. And frankly, there is way to more interesting and useful physics in low energy sector, involving scalar waves. The high energy collider experiments are essentially useless for industrial purposes - during last seventy years we found no usage for ANY particle revealed at colliders. The only "useful" particles are those, which occur at the Nature just because of their stability. The dense aether model is geometric one and IMO it's quite sufficient for qualitative explanation of the whole observable Universe at both cosmological, bot quantum scales.

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