Higgs boson

The Higgs boson is a fundamental particle associated with the Higgs field, which is responsible for giving mass to other particles through the mechanism of electroweak symmetry breaking. The mass of the Higgs boson itself is approximately 125 GeV/c². The Lagrangian density for the Higgs field can be expressed as:

+\begin{equation} \mathcal{L} = \frac{1}{2} \partial_\mu \phi \partial^\mu \phi - V(\phi) \end{equation}

where the potential V(\phi) is given by:

+\begin{equation} V(\phi) = \frac{\lambda}{4} \left( \phi^2 - v^2 \right)^2 \end{equation}

Here, \phi is the Higgs field, v is the vacuum expectation value, and \lambda is the self-coupling constant. The interaction of the Higgs boson with other particles can be described by the Yukawa coupling:

+\begin{equation} \mathcal{L}_{\text{Yukawa}} = -y_f \bar{\psi}_f \phi \psi_f \end{equation}

where y_f is the Yukawa coupling constant, \psi_f represents the fermion fields, and \bar{\psi}_f is the Dirac adjoint of the fermion field.