In particle physics, a hyperon is any baryon containing a strange quark, but no charm quarks or bottom quarks. Particle physics is a branch of Physics that studies the elementary constituents of Matter and Radiation, and the interactions between them Baryons are the family of Subatomic particles with a Baryon number of 1 The strange quark is a second- generation Quark with a charge of &minus(1/3 e and a strangeness of &minus1 The charm Quark is a second-generation quark with an electric charge of +(2/3 e. The bottom quark is a third-generation Quark with a charge of − e.

Properties and behavior of hyperons

A combination of three u, d or s-quarks with a total spin of 3/2 form the so-called baryon decuplet. The lower six are hyperons.

Being baryons, all hyperons are fermions. In Particle physics, fermions are particles which obey Fermi-Dirac statistics; they are named after Enrico Fermi. That is, they have half-integer spin and obey Fermi-Dirac statistics. In Mathematics, a half-integer is a Number of the form n + 1/2 where n is an Integer. In Quantum mechanics, spin is a fundamental property of atomic nuclei, Hadrons and Elementary particles For particles with non-zero spin In Statistical mechanics, Fermi-Dirac statistics is a particular case of Particle statistics developed by Enrico Fermi and Paul Dirac that They all interact via the strong nuclear force, making them types of hadron. In particle physics the strong interaction, or strong force, or color force, holds Quarks and Gluons together to form Protons and In Particle physics, a hadron ( from the ἁδρός hadrós, " stout, thick " ( They are composed of three light quarks, at least one of which is a strange quark, which makes them strange baryons. In Physics, a quark (kwɔrk kwɑːk or kwɑːrk is a type of Subatomic particle. The strange quark is a second- generation Quark with a charge of &minus(1/3 e and a strangeness of &minus1 Hyperons decay weakly with non-conserved parity. The weak interaction (often called the weak force or sometimes the weak nuclear force) is one of the four Fundamental interactions of nature

Types of hyperons

There are three Sigma hyperons, Σ⁺, Σ⁰ and Σ⁻. They have rest energies of ~1,190 MeV and lifetimes of ~1×10⁻¹⁰ s with the exception of Σ⁰ whose lifetime is shorter than 10×10⁻¹⁴ s. The rest energy E or rest mass-energy of a particle is its energy when it is at rest relative to a given Inertial reference frame.

There is one Lambda hyperon, Λ⁰. It has a rest energy of 1,115 MeV with a lifetime of 2. 6×10⁻¹⁰ s.

There are two Xi hyperons, Ξ⁰ and Ξ⁻. They have rest energies of 1,315 MeV and 1,320 MeV and lifetimes of 2. 9×10⁻¹⁰ s and 1. 6×10⁻¹⁰ s.

There is one Omega hyperon, the last discovered, Ω⁻, with a mass of 1,670 MeV and a lifetime of 8. 2×10⁻¹¹ s.

Hyperon decay

Since strangeness is conserved by the strong interactions, the ground-state hyperons cannot decay strongly. In particle physics the strong interaction, or strong force, or color force, holds Quarks and Gluons together to form Protons and However, they do participate in strong interactions.

Λ decay

Λ⁰ → p⁺ + π⁻

Λ⁰ → n⁰ + π⁰

Λ⁰ may also decay on rare occurrences via these processes

Λ⁰ → p⁺ + e⁻ + νe

Λ⁰ → p⁺ + μ⁻ + νμ

Σ decay

Σ⁺ → p⁺ + π⁰

Σ⁺ → n⁰ + π⁺

Σ⁰ → Λ⁰ + γ

Σ⁻ → n⁰ + π⁻

Ξ decay

Ξ⁰ → Λ⁰ + π⁰

Ξ⁻ → Λ⁰ + π⁻

Ξ particles are also known as "cascade" hyperons, since they go through a two-step cascading decay into a nucleon by first decaying to a Λ⁰ and emitting a π^±.

Ω⁻ decay

The Ω⁻ has a baryon number of +1 and hypercharge of -2 giving it strangeness of −3. In Particle physics, the baryon number is an approximate conserved Quantum number of a system In Particle physics, the hypercharge (represented by Y) of a particle is related to the Strong interaction, and it should not be confused with similarly It takes multiple flavor-changing weak decays for it to decay into a proton or neutron. The weak interaction (often called the weak force or sometimes the weak nuclear force) is one of the four Fundamental interactions of nature Murray Gell-Mann's SU(3) model (sometimes called the Eightfold Way) predicted this hyperon's existence, mass and that it will only undergo weak decay processes. Murray Gell-Mann (born September 15, 1929) is an American Physicist who received the 1969 Nobel Prize in physics for his work Special Unit 2In Mathematics, the special unitary group of degree n, denoted SU( n) is the group of n × n In Physics, the Eightfold Way is a term coined by American Physicist Murray Gell-Mann for a theory organizing subatomic Baryons

Experimental evidence for its existence was discovered in 1964 at Brookhaven National Laboratory. Brookhaven National Laboratory ( BNL) is a United States national laboratory located in Upton New York on Long Island, and was formally established Further examples of its formation and observation using particle accelerators confirmed the SU(3) model.

Ω⁻ → Ξ⁰+π⁻

Ξ⁰ → Λ⁰+π⁰

Λ⁰ → p+π⁻

Hyperon research

The first research into hyperons happened in the 1950s, and spurred physicists on to the creation of an organized classification of particles. Today, research in this area is carried out on data taken at many facilities around the world, including CERN, Fermilab, SLAC, JLAB, Brookhaven National Laboratory, KEK, and others. The European Organization for Nuclear Research (Organisation Européenne pour la Recherche Nucléaire known as CERN Fermi National Accelerator Laboratory ( Fermilab) located in Batavia near Chicago, Illinois, is a U The Stanford Linear Accelerator Center ( SLAC) is a United States Department of Energy National Laboratory operated by Stanford University under Thomas Jefferson National Accelerator Facility ( TJNAF) commonly called Jefferson Lab (JLAB is a U Brookhaven National Laboratory ( BNL) is a United States national laboratory located in Upton New York on Long Island, and was formally established The High Energy Accelerator Research Organization (高エネルギー加速器研究機構 Kō Enerugī Kasokuki Kenkyū Kikō) commonly known as KEK, is a High-energy Physics topics include searches for CP violation, measurements of spin, studies of excited states (commonly referred to as spectroscopy), and hunts for exotic states such as pentaquarks and dibaryons. In Particle physics, CP violation is a violation of the postulated CP symmetry of the laws of physics In Quantum mechanics, spin is a fundamental property of atomic nuclei, Hadrons and Elementary particles For particles with non-zero spin Excitation is an elevation in energy level above an arbitrary baseline energy state A pentaquark is an hypothetical subatomic particle consisting of a group of five Quarks (compared to three quarks in normal Baryons and two in Mesons, or Dibaryons are a large family of hypothetical particles that would consist of six Quarks of any flavors

List of hyperons

See also

• Delta baryon
• Hypernucleus
• Lambda baryon
• List of mesons
• List of particles
• Nucleon
• Omega baryon
• Physics portal
• Sigma baryon
• Timeline of particle discoveries
• Xi baryon

References

1. ^ Particle Data Groups: 2006 Review of Particle Physics - Lambda. In Particle physics, Lambda (Λ baryons are Baryons containing an Up quark, a Down quark, and a third quark either a Strange quark In Particle physics, a kaon (/ˈkeɪɒn/ also called K-meson and denoted) is any one of a group of four Mesons distinguished by the fact that they In Particle physics, (Xi is a name given to a range of Baryons with one up or down Quark and two heavier quarks In Particle physics, pion (short for pi meson) is the collective name for three Subatomic particles, and. In Particle physics, (Xi is a name given to a range of Baryons with one up or down Quark and two heavier quarks In Particle physics, pion (short for pi meson) is the collective name for three Subatomic particles, and. The Delta baryons are relatively light ( Baryons made of only up (u and down (d Quarks of Isospin 3/2 and spin 3/2 whose ground state parity A hypernucleus is a nucleus which contains at least one Hyperon in addition to Nucleons The first was discovered by Marian Danysz and Jerzy In Particle physics, Lambda (Λ baryons are Baryons containing an Up quark, a Down quark, and a third quark either a Strange quark This is a list of known and predicted Mesons. Mesons are made of Quarks and as such are part of the Subatomic particle family called the Hadrons This is a list of the different types of particles known and hypothesized In Physics a nucleon is a collective name for two Baryons the Neutron and the Proton. Omega (Ω baryons are Baryons containing neither up nor down quarks of Isospin I&thinsp=&thinsp0 See also Delta baryon Hyperon Lambda baryon List of mesons List of This is a Timeline of Subatomic particle discoveries, including all particles thus far discovered which appear to be elementary (that is indivisible given In Particle physics, (Xi is a name given to a range of Baryons with one up or down Quark and two heavier quarks Retrieved on [[April 20, 2008]]. Events 1303 - The University of Rome La Sapienza is instituted by Pope Boniface VIII. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
2. ^ Physics Particle Overview - Baryons. Retrieved on [[April 20, 2008]]. Events 1303 - The University of Rome La Sapienza is instituted by Pope Boniface VIII. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
3. ^ Particle Data Groups: 2006 Review of Particle Physics - Sigma+. Retrieved on [[April 20, 2008]]. Events 1303 - The University of Rome La Sapienza is instituted by Pope Boniface VIII. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
4. ^ Particle Data Groups: 2006 Review of Particle Physics - Sigma0. Retrieved on [[April 20, 2008]]. Events 1303 - The University of Rome La Sapienza is instituted by Pope Boniface VIII. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
5. ^ Particle Data Groups: 2006 Review of Particle Physics - Sigma-. Retrieved on [[April 20, 2008]]. Events 1303 - The University of Rome La Sapienza is instituted by Pope Boniface VIII. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
6. ^ ^{a b c} Particle Data Groups: 2006 Review of Particle Physics - Sigma(1385). Retrieved on [[April 20, 2008]]. Events 1303 - The University of Rome La Sapienza is instituted by Pope Boniface VIII. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
7. ^ Particle Data Groups: 2006 Review of Particle Physics - Xi0. Retrieved on [[April 20, 2008]]. Events 1303 - The University of Rome La Sapienza is instituted by Pope Boniface VIII. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
8. ^ Particle Data Groups: 2006 Review of Particle Physics - Xi-. Retrieved on [[April 20, 2008]]. Events 1303 - The University of Rome La Sapienza is instituted by Pope Boniface VIII. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
9. ^ ^{a b} Particle Data Groups: 2006 Review of Particle Physics - Xi(1530). Retrieved on [[April 20, 2008]]. Events 1303 - The University of Rome La Sapienza is instituted by Pope Boniface VIII. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
10. ^ Particle Data Groups: 2006 Review of Particle Physics - Omega-. Retrieved on [[April 20, 2008]]. Events 1303 - The University of Rome La Sapienza is instituted by Pope Boniface VIII. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common

• Henry Semat, John R. Albright (1984). Introduction to atomic and nuclear physics. Chapman and Hall. ISBN 0-412-15670-9.