The sigma-zero particle decays mostly via the reaction \[{{\rm{\Sigma }}^{\rm{0}}} \to {{\rm{\Lambda }}^{\rm{0}}}{\rm{ + \gamma }}\]. Explain how this decay and the respective quark compositions imply that the \[{{\rm{\Sigma }}^{\rm{0}}}\]is an excited state of the\[{{\rm{\Lambda }}^{\rm{0}}}\].

Short Answer

Expert verified

Baryons that are composed of the same quarks represents different states of the same particle thus having the same quark structure, \[{{\rm{\Sigma }}^{\rm{0}}}\] represents excited state of \[{{\rm{\Delta }}^{\rm{0}}}\]. The \[{{\rm{\Sigma }}^{\rm{0}}}\] decays to \[{{\rm{\Delta }}^{\rm{0}}}\] without violating the conservation of strangeness with \[{{\rm{\Delta }}^{\rm{0}}}\] the only less massive strange quark.

Step by step solution

01

Definition of Concept

The sigma zero decay relation in terms of quarks is given by,

\(uds \to uds + \gamma \)

02

Explain how this decay and the respective quark compositions imply

Sigma is a type of baryon with an unusual quark structure, uds, similar to how \[{{\rm{\Delta }}^{\rm{0}}}\] has the same quark structure, uds. Baryons made up of the same quarks represent different states of the same particle, resulting in the same quark structure; \[{{\rm{\Sigma }}^{\rm{0}}}\] represents the excited state of \[{{\rm{\Delta }}^{\rm{0}}}\]. The \[{{\rm{\Sigma }}^{\rm{0}}}\] decays to \[{{\rm{\Delta }}^{\rm{0}}}\], without breaking the law of conservation of strangeness, with \[{{\rm{\Delta }}^{\rm{0}}}\] being the only less massive strange quark.

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Most popular questions from this chapter

The principal decay mode of the sigma zero is \[{{\rm{\Sigma }}^{\rm{0}}}{\rm{ }} \to {\rm{ }}{{\rm{\Lambda }}^{\rm{0}}}{\rm{ + \gamma }}\]. (a) What energy is released? (b) Considering the quark structure of the two baryons, does it appear that the \[{{\rm{\Sigma }}^{\rm{0}}}\]is an excited state of the \[{{\rm{\Lambda }}^{\rm{0}}}\]? (c) Verify that strangeness, charge, and baryon number are conserved in the decay. (d) Considering the preceding and the short lifetime, can the weak force be responsible? State why or why not.

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