\documentclass[tikz]{standalone} \usetikzlibrary{patterns,decorations.markings} \tikzset{ dressed/.style={fill=white,postaction={pattern=north east lines}}, momentum/.style={->,semithick,yshift=5pt,shorten >=5pt,shorten <=5pt}, loop/.style 2 args={thick,decoration={markings,mark=at position {#1} with {\arrow{>},\node[anchor=\pgfdecoratedangle-90,font=\footnotesize] {$p_{#2}$};}},postaction={decorate}}, label/.style={thin,gray,shorten <=-1ex} } \def\lrad{1} \def\mrad{0.175*\lrad} \def\srad{0.15*\lrad} \begin{document} % Diagram 1 \begin{tikzpicture} % Loop \draw[loop/.list={{0.125}{1},{0.125*3}{2},{0.125*5}{3},{0.125*7}{4}}] (0,0) circle (\lrad); \draw[dressed] (0,\lrad) circle (\srad) node[above=2pt] {$G_{k,ij}(p_1,p_2)$}; \draw[dressed] (0,-\lrad) circle (\srad) node[below=3pt] {$G_{k,kl}(p_3,p_4)$}; % External lines \draw (-2*\lrad,0) coordinate (xl) -- (-\lrad,0) node[pos=0.4,below] {$\varphi_a$}; \draw[momentum] (-2*\lrad,0) -- (-1.25*\lrad,0) node[midway,above] {$q_1$}; \draw (\lrad,0) -- (2*\lrad,0) coordinate (xr) node[pos=0.6,below] {$\varphi_b$}; \draw[momentum] (1.25*\lrad,0) -- (2*\lrad,0) node[midway,above] {$q_2$}; % Vertices \node at (-2.1*\lrad,\lrad) (Gkajk) {$\Gamma_{k,ajk}^{(3)}(q_1,p_2,-p_3)$}; \draw[label] (Gkajk.-30) -- (-\lrad,0); \draw[dressed] (-\lrad,0) circle (\mrad); \node at (2.1*\lrad,\lrad) (Gkbli) {$\Gamma_{k,bli}^{(3)}(-q_2,-p_1,p_4)$}; \draw[label] (Gkbli.-150) -- (\lrad,0); \draw[dressed] (\lrad,0) circle (\mrad); \end{tikzpicture} % Diagram 2 \begin{tikzpicture} % Loop \draw[loop/.list={{0}{1},{0.125*4}{2}}] (0,0) circle (\lrad); \draw[dressed] (0,\lrad,0) circle (\srad) node[above=2pt] {$G_{k,ij}(p_1,p_2)$}; % External lines \draw (-2*\lrad,-\lrad) node[left] {$\varphi_a$} -- (2*\lrad,-\lrad) node[right] {$\varphi_b$}; \draw[momentum] (-2*\lrad,-\lrad) -- (-\lrad,-\lrad) node[midway,above] {$q_1$}; \draw[momentum] (\lrad,-\lrad) -- (2*\lrad,-\lrad) node[midway,above] {$q_2$}; % Vertices \draw[dressed] (0,-\lrad) circle (\mrad) node[below] {$\Gamma_{k,abji}^{(4)}(q_1,-q_2,-p_1,p_2)$}; \end{tikzpicture} \end{document}