Question

For which particles does table 12.2 showboth particles and anti-particles?Which particles are their own antiparticles?

Short answer

Particles that are acting as antiparticles of themselves are either having a strangeness of 0, or they have mixed strangeness.Also, ${\text{I}}_3$ and the strangeness data is following the same trend.

Step-by-step solution

Given data

The given data is shown below.

Concept of Fundamental particles

According to Quantum Mechanics, the fundamental particles have their respective anti-particles, which have the same mass but differ in their other properties.Each subatomic particle would have an anti-particle like the anti-particle of the electron is a positron for proton, its anti-proton, and for neutron, its antineutrino.

Explanation of the particles and anti-particles with respect to each other 

In the given data, the particles which show both particle and anti-particle could be obtained if they have the same values of mass, spin, and same l .

The sign of strangeness and spin must be opposite.

The particles like photons are generally antiparticles of themselves, but from the given data, the following would be considered as the anti-particles of themselves.

Hence, from the table, it can beseen that particles that are acting as antiparticles of themselves are either having a strangeness ofor they have mixed strangeness.

Also, ${\text{I}}_3$ and the strangeness data is following the same trend.