| Vorderseite | [latex]What is the property 'color' in the context of particle physics?[/latex] |
| Rückseite | [latex]'Color' is a property that is inherited by quarks. Color can take the values red, green or blue. While quarks inherit color, hadrons must be colorless. This can be achieved by a combination of red, green and blue or a color and the corresponding anti-color. Single quarks can never be observed, which is called 'confinement'. Gluons couple to color.[/latex] |
| Vorderseite | [latex]Name all invariant quantities of particle physics.[/latex] |
| Rückseite | [latex]\begin{itemize} \item Energy, momentum, total angular momentum \item Charge \item Color \item Baryon number $ B \\ (B(q)=\frac{1}{3}, B(\bar{q})=-\frac{1}{3}, B(other)=0) $\item Lepton number $ L \\ (L(l)=+1, L(\bar{l})=-1, L(other)=0) $ \item Flavor is not an invariant, as it can be changed by the weak interaction only \end{itemize}[/latex] |
| Vorderseite | [latex]Calculate the center-of-mass energy for a fixed-target experiment.[/latex] |
| Rückseite | [latex]$ p_1 = \begin{pmatrix} E_1 \\ \vec{p}_1 \end{pmatrix} $ , $ p_2 = \begin{pmatrix} m_2 \\ 0 \end{pmatrix} $ \\ \\ \begin{align} \notag E^2_{CM} = s & = (E_1+E_2)^2 - (\vec{p}_1 + \vec{p}_2)^2 \\ \notag & = E_1^2 + m_2^2 + 2E_1m_2 - \vec{p}_1^2 \\ \notag & = m_1^2 + m_2^2 + 2E_1m_2 \\ & \notag= 2E_1m_2 \end{align} using $ E >> m $ \\ \\ $ \Leftrightarrow E_{CM} = \sqrt{2E_1m_2} $ [/latex] |