Upsilon meson: Difference between revisions

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Upsilon Meson

Quark structure of bottomonium, including the Upsilon meson.

The Upsilon meson (_) is a family of mesons formed from a bottom quark and its antiparticle, the bottom antiquark. It is a type of bottomonium, a bound state of a bottom quark and its antiquark. The Upsilon meson was first discovered in 1977 by the E288 experiment at Fermilab.

Discovery

The discovery of the Upsilon meson was a significant event in the field of particle physics. It was first observed by a team led by Leon M. Lederman at Fermilab. The team detected the Upsilon meson through its decay into a pair of muons, which produced a distinct peak in the invariant mass distribution of the muon pairs. This peak, known as the Upsilon peak, was a clear indication of a new particle.

Properties

The Upsilon meson is a neutral particle with a mass of approximately 9.46 GeV/c_. It is the lightest of the bottomonium states and has a relatively long lifetime compared to other mesons. The Upsilon meson can decay into various final states, including pairs of leptons such as muons and electrons, as well as hadrons.

Significance

The study of the Upsilon meson and other bottomonium states provides valuable insights into the strong force, one of the four fundamental forces of nature. The strong force is responsible for binding quarks together to form protons, neutrons, and other particles. By studying the properties and decay modes of the Upsilon meson, physicists can test predictions of quantum chromodynamics (QCD), the theory that describes the strong interaction.

Related pages

References

Lederman, L. M., et al. "Observation of a Dimuon Resonance at 9.5 GeV in 400-GeV Proton-Nucleus Collisions." Physical Review Letters, vol. 39, no. 5, 1977, pp. 252-255.
"Upsilon Meson." Particle Data Group. Retrieved from [1].

Template:Particle physics

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-'''Upsilon meson''' ([[Particle physics|particle physics]]) is a family of [[subatomic particle]]s that are understood within the framework of [[quantum mechanics]] and [[quantum field theory]]. These particles are examples of [[quarkonium]], which are bound states of a [[quark]] and an [[antiquark]]. Specifically, the Upsilon meson consists of a bottom quark (b) and its corresponding antibottom quark (\(\bar{b}\)), making it a form of [[bottomonium]]. The discovery of the Upsilon meson significantly contributed to the development of the [[Standard Model]] of particle physics, providing key evidence for the existence of the bottom quark.
+== Upsilon Meson ==
-==Discovery==
+[[File:Upsilon_peak.jpg|thumb|right|The Upsilon peak observed in particle collision experiments.]]
-The Upsilon meson was first observed in 1977 at the [[Fermilab]] in experiments led by physicist [[Leon M. Lederman]]. The discovery was made using a [[particle accelerator]] to collide protons with fixed targets, resulting in the production of various particles, including the Upsilon meson. This discovery was pivotal in confirming the existence of the third generation of quarks, specifically the bottom quark, which had been theorized but not yet observed.
+[[File:Quark_structure_bottomonium.svg|thumb|right|Quark structure of bottomonium, including the Upsilon meson.]]
-==Properties==
+The '''Upsilon meson''' (_) is a family of [[meson]]s formed from a [[bottom quark]] and its [[antiparticle]], the bottom antiquark. It is a type of [[bottomonium]], a bound state of a bottom quark and its antiquark. The Upsilon meson was first discovered in 1977 by the [[E288 experiment]] at [[Fermilab]].
-The Upsilon meson is characterized by its mass, spin, and decay modes. It is a [[vector meson]], meaning it has a spin of 1. The mass of the Upsilon meson is approximately 9.46 GeV/c^2, making it one of the heaviest mesons due to the significant mass of the bottom quark. The Upsilon meson exists in several excited states, denoted as Υ(1S), Υ(2S), Υ(3S), etc., with the ground state being Υ(1S). These excited states decay into the ground state through the emission of [[photon]]s.
-==Decay==
+== Discovery ==
-The Upsilon meson primarily decays into three gluons, which subsequently hadronize to produce a variety of hadrons. This decay process is mediated by the strong force, as described by [[Quantum Chromodynamics]] (QCD). The Upsilon meson can also decay into a pair of leptons (electron-positron or muon-antimuon pairs) through the electromagnetic force, providing a clean signature for its detection in experiments.
-==Significance in Particle Physics==
+The discovery of the Upsilon meson was a significant event in the field of [[particle physics]]. It was first observed by a team led by [[Leon M. Lederman]] at Fermilab. The team detected the Upsilon meson through its decay into a pair of [[muon]]s, which produced a distinct peak in the invariant mass distribution of the muon pairs. This peak, known as the Upsilon peak, was a clear indication of a new particle.
-The study of the Upsilon meson and its properties has provided valuable insights into the nature of the strong force and the behavior of quarks bound in mesons. Measurements of the mass and decay modes of the Upsilon meson have contributed to the refinement of QCD and the parameters of the Standard Model. Furthermore, the study of its excited states has offered a deeper understanding of quark-antiquark binding energies and the potential models describing the interactions between quarks.
-==See Also==
+== Properties ==
-* [[Quark]]
-* [[Antiquark]]
-* [[Quarkonium]]
-* [[Standard Model]]
-* [[Quantum Chromodynamics]]
-* [[Particle accelerator]]
-[[Category:Particle physics]]
+The Upsilon meson is a neutral particle with a mass of approximately 9.46 [[GeV/c_]]. It is the lightest of the bottomonium states and has a relatively long lifetime compared to other mesons. The Upsilon meson can decay into various final states, including pairs of leptons such as muons and electrons, as well as hadrons.
+== Significance ==
+The study of the Upsilon meson and other bottomonium states provides valuable insights into the strong force, one of the four fundamental forces of nature. The strong force is responsible for binding quarks together to form protons, neutrons, and other particles. By studying the properties and decay modes of the Upsilon meson, physicists can test predictions of [[quantum chromodynamics]] (QCD), the theory that describes the strong interaction.
+== Related pages ==
+* [[Bottom quark]]
+* [[Meson]]
+* [[Quantum chromodynamics]]
+* [[Fermilab]]
+== References ==
+* Lederman, L. M., et al. "Observation of a Dimuon Resonance at 9.5 GeV in 400-GeV Proton-Nucleus Collisions." Physical Review Letters, vol. 39, no. 5, 1977, pp. 252-255.
+* "Upsilon Meson." Particle Data Group. Retrieved from [https://pdg.lbl.gov/].
+{{Particle physics}}
 [[Category:Mesons]]
-{{Physics-stub}}
+[[Category:Bottomonium]]