Λ-baryon

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Lambda Baryon (Λ 0 )

classification
Fermion
Hadron
Baryon
properties
electric charge neutral
Resting energy 1115.683 ± 0.006  MeV
magnetic moment -0.613 ± 0.004  μ N
Spin parity 1 ⁄ 2 +
Isospin 0
Strangeness −1
average lifespan (2.632 ± 0.020) · 10 −10  s
Quark
composition 		uds

Λ c + -baryon

classification
Fermion
Hadron
Baryon
properties
electric charge 1  e
(+1.602 10 −19  C )
Resting energy 2286.46 ± 0.14  MeV
Spin parity 1 ⁄ 2 +
Isospin 0
Charm +1
average lifespan (2.00 ± 0.06) 10 −13  s
Quark
composition 		udc

Λ b 0 -Baryon

classification
Fermion
Hadron
Baryon
properties
electric charge neutral
Resting energy 5619.60 ± 0.17  MeV
Beauty −1
average lifespan (1.470 ± 0.010) · 10 −12  s
Quark
composition 		udb

The Λ-baryon , also known as lambda baryon , is a baryon that consists of an up , a down and a strange quark . It has spin  1/2, isospin  0, is electrically neutral and is therefore sometimes referred to as Λ 0 .

The Λ-baryon belongs to the class of hyperons .

description

The SU (3) -Baryon Octet (Spin 1/2)

The Λ 0 -baryon belongs to the SU (3) octet.

Almost 100% of it breaks down into a nucleon and a pion . The decay into a proton and a π - with 63.9% almost twice as likely as the decay into a neutron and a π 0 (35.8%).

About 17 resonances (short-lived excited states) of the Λ-baryon have been more or less unequivocally proven.

Λ c and Λ b

Heavy baryons have been detected that have a charm quark or a bottom quark instead of the s quark, i.e. with the quark composition udc and udb . They are referred to as Λ c (or Λ c + ) or Λ b (or Λ b 0 ) and are the lightest baryons with c or b quarks.

See also

Individual evidence

  1. ↑ a b c d The information on the particle properties (info box) are, unless otherwise stated, taken from:
    M. Tanabashi et al .: 2018 Review of Particle Physics. In: Phys. Rev. D 98, 030001 (2018). Particle Data Group, accessed June 8, 2018 .