The Upsilon meson () is a
quarkonium state (i.e.
flavourless meson
In particle physics, a meson () is a type of hadronic subatomic particle composed of an equal number of quarks and antiquarks, usually one of each, bound together by the strong interaction. Because mesons are composed of quark subparticles, the ...
) formed from a
bottom quark
The bottom quark, beauty quark, or b quark, is an elementary particle of the third generation. It is a heavy quark with a charge of − ''e''.
All quarks are described in a similar way by electroweak interaction and quantum chromodynamic ...
and its
antiparticle
In particle physics, every type of particle of "ordinary" matter (as opposed to antimatter) is associated with an antiparticle with the same mass but with opposite physical charges (such as electric charge). For example, the antiparticle of the ...
. It was discovered by the
E288 experiment team, headed by
Leon Lederman
Leon, Léon (French) or León (Spanish) may refer to:
Places
Europe
* León, Spain, capital city of the Province of León
* Province of León, Spain
* Kingdom of León, an independent state in the Iberian Peninsula from 910 to 1230 and again fro ...
, at
Fermilab
Fermi National Accelerator Laboratory (Fermilab), located in Batavia, Illinois, near Chicago, is a United States Department of Energy United States Department of Energy National Labs, national laboratory specializing in high-energy particle phys ...
in 1977, and was the first particle containing a bottom quark to be discovered because it is the lightest that can be produced without additional massive particles. It has a
lifetime of and a mass about in the ground state.
File:Quark structure bottomonium.svg, Quark structure of the Upsilon meson
See also
*
Oops-Leon, an erroneously-claimed discovery of a similar particle at a lower mass in 1976.
* The particle is the analogous state made from
strange quark
The strange quark or s quark (from its symbol, s) is the third lightest of all quarks, a type of elementary particle. Strange quarks are found in subatomic particles called hadrons. Examples of hadrons containing strange quarks include kaons (), ...
s.
* The particle is the analogous state made from
charm quark
The charm quark, charmed quark, or c quark is an elementary particle found in composite subatomic particles called hadrons such as the J/psi meson and the charmed baryons created in particle accelerator collisions. Several bosons, including th ...
s.
*
List of mesons
: ''This list is of all known and predicted scalar, pseudoscalar and vector mesons. See list of particles for a more detailed list of particles found in particle physics.''
This article contains a list of mesons, unstable subatomic particles ...
References
*
*
*
Mesons
Onia
Subatomic particles with spin 1
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