The lambda hyperon (0) is a particle composed of one up, one down and one strange quark. (i) What classification of particle is a lambda hyperon? (ii) Identify the electric charge on the lambda hyperon.
SAMPLE ANSWER 23G (i) It is composed of three quarks. It is therefore a baryon.
The lambda hyperon (0) is electrically neutral. ∂0 uds a2
(ii) 3b a1 3b a1 3b 0.
QUARK COMPOSITION OF SOME HADRONS Quark
Type Name proton
neutron antiproton sigma
charm lambda
delta
charged pion
charged antikaon
neutral kaon
phi
Symbol composition p
uud n p π ¶ 0 udd uud dds udc uuu ud us ds ss Table 23.4: : Examples of some hadrons, giving their quark composition Quark charge
a2 3 b a2
a2 3 b a1
a2 3 b a2
a1 3 b a1
a 2 3 b a 1
a 2 3 b a 2
3 b a1 3 b a1 3 b a1 3 b a1 3 b a 2 3 b a 2