Examples - TikZ-Feynman Manual

$\newcommand{\footnotename}{footnote}$ $\def \LWRfootnote {1}$ $\newcommand {\footnote }[2][\LWRfootnote ]{{}^{\mathrm {#1}}}$ $\newcommand {\footnotemark }[1][\LWRfootnote ]{{}^{\mathrm {#1}}}$ $\let \LWRorighspace \hspace $ $\renewcommand {\hspace }{\ifstar \LWRorighspace \LWRorighspace }$ $\newcommand {\TextOrMath }[2]{#2}$ $\newcommand {\mathnormal }[1]{{#1}}$ $\newcommand \ensuremath [1]{#1}$ $\newcommand {\LWRframebox }[2][]{\fbox {#2}} \newcommand {\framebox }[1][]{\LWRframebox } $ $\newcommand {\setlength }[2]{}$ $\newcommand {\addtolength }[2]{}$ $\newcommand {\setcounter }[2]{}$ $\newcommand {\addtocounter }[2]{}$ $\newcommand {\arabic }[1]{}$ $\newcommand {\number }[1]{}$ $\newcommand {\noalign }[1]{\text {#1}\notag \\}$ $\newcommand {\cline }[1]{}$ $\newcommand {\directlua }[1]{\text {(directlua)}}$ $\newcommand {\luatexdirectlua }[1]{\text {(directlua)}}$ $\newcommand {\protect }{}$ $\def \LWRabsorbnumber #1 {}$ $\def \LWRabsorbquotenumber "#1 {}$ $\newcommand {\LWRabsorboption }[1][]{}$ $\newcommand {\LWRabsorbtwooptions }[1][]{\LWRabsorboption }$ $\def \mathchar {\ifnextchar "\LWRabsorbquotenumber \LWRabsorbnumber }$ $\def \mathcode #1={\mathchar }$ $\let \delcode \mathcode $ $\let \delimiter \mathchar $ $\def \oe {\unicode {x0153}}$ $\def \OE {\unicode {x0152}}$ $\def \ae {\unicode {x00E6}}$ $\def \AE {\unicode {x00C6}}$ $\def \aa {\unicode {x00E5}}$ $\def \AA {\unicode {x00C5}}$ $\def \o {\unicode {x00F8}}$ $\def \O {\unicode {x00D8}}$ $\def \l {\unicode {x0142}}$ $\def \L {\unicode {x0141}}$ $\def \ss {\unicode {x00DF}}$ $\def \SS {\unicode {x1E9E}}$ $\def \dag {\unicode {x2020}}$ $\def \ddag {\unicode {x2021}}$ $\def \P {\unicode {x00B6}}$ $\def \copyright {\unicode {x00A9}}$ $\def \pounds {\unicode {x00A3}}$ $\let \LWRref \ref $ $\renewcommand {\ref }{\ifstar \LWRref \LWRref }$ $ \newcommand {\multicolumn }[3]{#3}$ $\require {textcomp}$ $\newcommand {\meta }[1]{\langle \textit {#1}\rangle }$ $\newcommand {\intertext }[1]{\text {#1}\notag \\}$ $\let \Hat \hat $ $\let \Check \check $ $\let \Tilde \tilde $ $\let \Acute \acute $ $\let \Grave \grave $ $\let \Dot \dot $ $\let \Ddot \ddot $ $\let \Breve \breve $ $\let \Bar \bar $ $\let \Vec \vec $ $\require {mathtools}$ $\newcommand {\vcentcolon }{\mathrel {\unicode {x2236}}}$ $\newcommand {\approxcolon }{\approx \vcentcolon }$ $\newcommand {\Approxcolon }{\approx \dblcolon }$ $\newcommand {\simcolon }{\sim \vcentcolon }$ $\newcommand {\Simcolon }{\sim \dblcolon }$ $\newcommand {\dashcolon }{\mathrel {-}\vcentcolon }$ $\newcommand {\Dashcolon }{\mathrel {-}\dblcolon }$ $\newcommand {\colondash }{\vcentcolon \mathrel {-}}$ $\newcommand {\Colondash }{\dblcolon \mathrel {-}}$ $\newenvironment {crampedsubarray}[1]{}{}$ $\newcommand {\smashoperator }[2][]{#2\limits }$ $\newcommand {\SwapAboveDisplaySkip }{}$ $\newcommand {\LaTeXunderbrace }[1]{\underbrace {#1}}$ $\newcommand {\LaTeXoverbrace }[1]{\overbrace {#1}}$ $\Newextarrow \xLongleftarrow {10,10}{0x21D0}$ $\Newextarrow \xLongrightarrow {10,10}{0x21D2}$ $\let \xlongleftarrow \xleftarrow $ $\let \xlongrightarrow \xrightarrow $ $\newcommand {\LWRmultlined }[1][]{\begin {multline*}}$ $\newenvironment {multlined}[1][]{\LWRmultlined }{\end {multline*}}$ $\let \LWRorigshoveleft \shoveleft $ $\renewcommand {\shoveleft }[1][]{\LWRorigshoveleft }$ $\let \LWRorigshoveright \shoveright $ $\renewcommand {\shoveright }[1][]{\LWRorigshoveright }$ $\newcommand {\shortintertext }[1]{\text {#1}\notag \\}$ $\require {centernot}$ $\newcommand {\LWRoverlaysymbols }[2]{\mathord {\smash {\mathop {#2\strut }\limits ^{\smash {\lower 3ex{#1}}}}\strut }}$ $\newcommand {\mmapsto }{\mathrel {\unicode {x021A6}}}$ $\let \mmapstochar \mmapsto $ $\newcommand {\longmmapsto }{\mathrel {\unicode {x021A6}}}$ $\newcommand {\mmappedfrom }{\mathrel {\unicode {x021A4}}}$ $\let \mmappedfromchar \mmappedfrom $ $\newcommand {\longmmappedfrom }{\mathrel {\unicode {x021A4}}}$ $\let \mmapsfrom \mmappedfrom $ $\let \longmmapsfrom \longmmappedfrom $ $\newcommand {\Mmapsto }{\mathrel {\unicode {x02907}}}$ $\let \Mmapstochar \Mmapsto $ $\newcommand {\Longmmapsto }{\mathrel {\unicode {x027FE}}}$ $\newcommand {\Mmappedfrom }{\mathrel {\unicode {x02906}}}$ $\let \Mmappedfromchar \Mmappedfrom $ $\newcommand {\Longmmappedfrom }{\mathrel {\unicode {x027FD}}}$ $\let \Mmapsfrom \Mmappedfrom $ $\let \Longmmapsfrom \Longmmappedfrom $ $\newcommand {\boxright }{\mathrel {\unicode {x025A1}\!\unicode {x02192}}}$ $\newcommand {\boxleft }{\mathrel {\unicode {x02190}\!\unicode {x025A1}}}$ $\newcommand {\boxdotright }{\mathrel {\unicode {x022A1}\!\unicode {x02192}}}$ $\newcommand {\boxdotleft }{\mathrel {\unicode {x02190}\!\unicode {x022A1}}}$ $\newcommand {\Diamondright }{\mathrel {\unicode {x025C7}\!\unicode {x02192}}}$ $\newcommand {\Diamondleft }{\mathrel {\unicode {x02190}\!\unicode {x025C7}}}$ $\newcommand {\Diamonddotright }{\mathrel {\unicode {x027D0}\!\unicode {x02192}}}$ $\newcommand {\Diamonddotleft }{\mathrel {\unicode {x02190}\!\unicode {x027D0}}}$ $\newcommand {\boxRight }{\mathrel {\unicode {x025A1}\!\unicode {x021D2}}}$ $\newcommand {\boxLeft }{\mathrel {\unicode {x021D0}\!\unicode {x025A1}}}$ $\newcommand {\boxdotRight }{\mathrel {\unicode {x022A1}\!\unicode {x021D2}}}$ $\newcommand {\boxdotLeft }{\mathrel {\unicode {x021D0}\!\unicode {x022A1}}}$ $\newcommand {\DiamondRight }{\mathrel {\unicode {x025C7}\!\unicode {x021D2}}}$ $\newcommand {\DiamondLeft }{\mathrel {\unicode {x021D0}\!\unicode {x025C7}}}$ $\newcommand {\DiamonddotRight }{\mathrel {\unicode {x027D0}\!\unicode {x021D2}}}$ $\newcommand {\DiamonddotLeft }{\mathrel {\unicode {x021D0}\!\unicode {x027D0}}}$ $\newcommand {\Diamonddot }{\mathrel {\unicode {x027D0}}}$ $\newcommand {\circleright }{\mathrel {\unicode {x025CB}\!\unicode {x02192}}}$ $\newcommand {\circleleft }{\mathrel {\unicode {x02190}\!\unicode {x025CB}}}$ $\newcommand {\circledotright }{\mathrel {\unicode {x02299}\!\unicode {x02192}}}$ $\newcommand {\circledotleft }{\mathrel {\unicode {x02190}\!\unicode {x02299}}}$ $\let \circleddotright \circledotright $ $\let \circleddotleft \circledotleft $ $\newcommand {\multimapinv }{\mathrel {\unicode {x027DC}}}$ $\newcommand {\multimapboth }{\mathrel {\unicode {x029DF}}}$ $\newcommand {\multimapdot }{{\mathrel {-\!\bullet }}}$ $\newcommand {\multimapdotinv }{\mathrel {\bullet \!-}}$ $\newcommand {\multimapdotboth }{\mathrel {{\bullet \!\!-\!\!\bullet }}}$ $\newcommand {\multimapdotbothA }{\mathrel {\unicode {x022B6}}}$ $\newcommand {\multimapdotbothB }{\mathrel {\unicode {x22B7}}}$ $\newcommand {\multimapbothvert }{\mathrel {\overset {\unicode {x025CB}}{\underset {\unicode {x025CB}}{|}}}}$ $\newcommand {\multimapdotbothvert }{\mathrel {\overset {\unicode {x025CF}}{\underset {\unicode {x025CF}}{|}}}}$ $\newcommand {\multimapdotbothBvert }{\mathrel {\overset {\unicode {x025CF}}{\underset {\unicode {x025CB}}{|}}}}$ $\newcommand {\multimapdotbothAvert }{\mathrel {\overset {\unicode {x025CB}}{\underset {\unicode {x025CF}}{|}}}}$ $\newcommand {\bignplus }{\mathop {\LWRoverlaysymbols {\unicode {xFF0B}}{\unicode {x22C2}}}}$ $\let \bigcapplus \bignplus $ $\let \capplus \bignplus $ $\newcommand {\bigsqcapplus }{\mathop {\LWRoverlaysymbols {\unicode {xFF0B}}{\unicode {x2A05}}} }$ $\let \sqcapplus \bigsqcapplus $ $\newcommand {\bigsqcupplus }{\mathop {\LWRoverlaysymbols {\unicode {xFF0B}}{\unicode {x2A06}}} }$ $\let \sqcupplus \bigsqcupplus $ $\newcommand {\parallelslant }{\mathrel {\unicode {x02AFD}}}$ $\newcommand {\parallelbackslant }{\mathrel {\unicode {x0005C}\!\!\unicode {x0005C}}}$ $\newcommand {\Eqqcolon }{\mathrel {=\!\unicode {x2237}}}$ $\let \eqqColon \Eqqcolon $ $\newcommand {\dashColon }{\mathrel {-\unicode {x2237}}}$ $\newcommand {\Colondash }{\mathrel {\unicode {x2237}-}}$ $\newcommand {\colonapprox }{\mathrel {:\approx }}$ $\newcommand {\colonsim }{\mathrel {:\sim }}$ $\newcommand {\Colonapprox }{\mathrel {\unicode {x2237}\!\approx }}$ $\newcommand {\Colonsim }{\mathrel {\unicode {x2237}\!\sim }}$ $\newcommand {\strictif }{\mathrel {\unicode {x0297D}}}$ $\newcommand {\strictfi }{\mathrel {\unicode {x0297C}}}$ $\newcommand {\strictiff }{\mathrel {\unicode {x0297C}\!\!\unicode {x0297D}}}$ $\newcommand {\circledwedge }{\mathbin {\LWRoverlaysymbols {\unicode {x025EF}}{\unicode {x02227}}}}$ $\newcommand {\circledvee }{\mathbin {\LWRoverlaysymbols {\unicode {x025EF}}{\unicode {0x02228}}}}$ $\newcommand {\circledbar }{\mathbin {\unicode {x029B6}}}$ $\newcommand {\openJoin }{\mathrel {\unicode {x2AA4}}}$ $\newcommand {\opentimes }{\mathrel {\unicode {x2AA4}}}$ $\newcommand {\VvDash }{\mathrel {\unicode {x22AA}}}$ $\newcommand {\lambdabar }{\mathord {\LWRoverlaysymbols {\raise {.5ex}{-}}{\lambda }}}$ $\newcommand {\lambdaslash }{\mathord {\unicode {x019B}}}$ $\newcommand {\Wr }{\mathbin {\unicode {x02240}\!\unicode {x02240}}}$ $\newcommand {\dashleftrightarrow }{\mathrel {\unicode {x021E0}\!\unicode {x021E2}}}$ $\let \leftrightdasharrow \dashleftrightarrow $ $\newcommand {\fAlt }{f}$ $\newcommand {\rhoAlt }{\rho }$ $\newcommand {\imathscr }{\mathord {\mathscr {i}}}$ $\newcommand {\jmathscr }{\mathord {\mathscr {j}}}$ $\let \llbracket \lBrack $ $\let \rrbracket \rBrack $ $\let \smlbrace \{$ $\let \smrbrace \}$ $\newcommand {\Perp }{\mathrel {\unicode {x02AEB}}}$ $\newcommand {\nPerp }{\mathrel {\not {\!\unicode {x02AEB}}}}$ $\newcommand {\Zbar }{\mathord {\unicode {x01B5}}}$ $\newcommand {\Angstrom }{\mathord {\unicode {x212B}}}$ $\newcommand {\Euler }{\mathord {\unicode {x2107}}}$ $\newcommand {\transp }{\mathord {\unicode {xFF34}}}$ $\newcommand {\hermtransp }{\mathord {\unicode {xFF28}}}$ $\let \htransp =\hermtransp $ $\newcommand {\circledplus }{\mathbin {\unicode {x2295}}}$ $\newcommand {\circledminus }{\mathbin {\unicode {x2296}}}$ $\newcommand {\circledtimes }{\mathbin {\unicode {x2297}}}$ $\newcommand {\circledslash }{\mathbin {\unicode {x2298}}}$ $\newcommand {\circleddot }{\mathbin {\unicode {x2299}}}$ $\let \overgroup \overparen $ $\let \overgroupra \overrightarrow $ $\let \undergroup \underparen $ $\let \undergroupla \underleftarrow $ $\newcommand {\widering }[1]{\stackrel {\unicode {x2218}}{\overgroup {#1}}}$ $\let \widearc \overparen $ $\let \wideOarc \overrightarrow $ $\newcommand {\LWRvvstar }[2]{{\overrightarrow {#1}_{#2}}}$ $\newcommand {\vv }{\ifstar \LWRvvstar \overrightarrow }$ $\let \smallintsl \smallint $ $\newcommand {\smalliintsl }{\mathop {\unicode {x222C}}\limits }$ $\newcommand {\smalliiintsl }{\mathop {\unicode {x222D}}\limits }$ $\newcommand {\smalliiiintsl }{\mathop {\unicode {x2A0C}}\limits }$ $\newcommand {\smallointsl }{\mathop {\unicode {x222E}}\limits }$ $\newcommand {\smalloiintsl }{\mathop {\unicode {x222F}}\limits }$ $\newcommand {\smalloiiintsl }{\mathop {\unicode {x2230}}\limits }$ $\newcommand {\smallvarointclockwisesl }{\mathop {\unicode {x2232}}\limits }$ $\newcommand {\smallointctrclockwisesl }{\mathop {\unicode {x2233}}\limits }$ $\newcommand {\smallsumintsl }{\mathop {\unicode {x2A0B}}\limits }$ $\newcommand {\smallfintsl }{\mathop {\unicode {x2A0F}}\limits }$ $\newcommand {\smallsqintsl }{\mathop {\unicode {x2A16}}\limits }$ $\let \smallintup \smallint $ $\newcommand {\smalliintup }{\mathop {\unicode {x222C}}\limits }$ $\newcommand {\smalliiintup }{\mathop {\unicode {x222D}}\limits }$ $\newcommand {\smalliiiintup }{\mathop {\unicode {x2A0C}}\limits }$ $\newcommand {\smallointup }{\mathop {\unicode {x222E}}\limits }$ $\newcommand {\smalloiintup }{\mathop {\unicode {x222F}}\limits }$ $\newcommand {\smalloiiintup }{\mathop {\unicode {x2230}}\limits }$ $\newcommand {\smallvarointclockwiseup }{\mathop {\unicode {x2232}}\limits }$ $\newcommand {\smallointctrclockwiseup }{\mathop {\unicode {x2233}}\limits }$ $\newcommand {\smallsumintup }{\mathop {\unicode {x2A0B}}\limits }$ $\newcommand {\smallfintup }{\mathop {\unicode {x2A0F}}\limits }$ $\newcommand {\smallsqintup }{\mathop {\unicode {x2A16}}\limits }$ $\newcommand {\iint }{\mathop {\unicode {x222C}}\limits }$ $\newcommand {\iiint }{\mathop {\unicode {x222D}}\limits }$ $\newcommand {\iiiint }{\mathop {\unicode {x2A0C}}\limits }$ $\newcommand {\oiint }{\mathop {\unicode {x222F}}\limits }$ $\newcommand {\oiiint }{\mathop {\unicode {x2230}}\limits }$ $\newcommand {\varointclockwise }{\mathop {\unicode {x2232}}\limits }$ $\newcommand {\ointctrclockwise }{\mathop {\unicode {x2233}}\limits }$ $\newcommand {\sumint }{\mathop {\unicode {x2A0B}}\limits }$ $\newcommand {\fint }{\mathop {\unicode {x2A0F}}\limits }$ $\newcommand {\sqint }{\mathop {\unicode {x2A16}}\limits }$ $\let \intsl \int $ $\newcommand {\iintsl }{\mathop {\unicode {x222C}}\limits }$ $\newcommand {\iiintsl }{\mathop {\unicode {x222D}}\limits }$ $\newcommand {\iiiintsl }{\mathop {\unicode {x2A0C}}\limits }$ $\let \ointsl \oint $ $\newcommand {\oiintsl }{\mathop {\unicode {x222F}}\limits }$ $\newcommand {\oiiintsl }{\mathop {\unicode {x2230}}\limits }$ $\newcommand {\varointclockwisesl }{\mathop {\unicode {x2232}}\limits }$ $\newcommand {\ointctrclockwisesl }{\mathop {\unicode {x2233}}\limits }$ $\newcommand {\sumintsl }{\mathop {\unicode {x2A0B}}\limits }$ $\newcommand {\fintsl }{\mathop {\unicode {x2A0F}}\limits }$ $\newcommand {\sqintsl }{\mathop {\unicode {x2A16}}\limits }$ $\let \intup \int $ $\newcommand {\iintup }{\mathop {\unicode {x222C}}\limits }$ $\newcommand {\iiintup }{\mathop {\unicode {x222D}}\limits }$ $\newcommand {\iiiintup }{\mathop {\unicode {x2A0C}}\limits }$ $\let \ointup \oint $ $\newcommand {\oiintup }{\mathop {\unicode {x222F}}\limits }$ $\newcommand {\oiiintup }{\mathop {\unicode {x2230}}\limits }$ $\newcommand {\varointclockwiseup }{\mathop {\unicode {x2232}}\limits }$ $\newcommand {\ointctrclockwiseup }{\mathop {\unicode {x2233}}\limits }$ $\newcommand {\sumintup }{\mathop {\unicode {x2A0B}}\limits }$ $\newcommand {\fintup }{\mathop {\unicode {x2A0F}}\limits }$ $\newcommand {\sqintup }{\mathop {\unicode {x2A16}}\limits }$ $\newcommand {\bigcupdot }{\mathop {\unicode {x2A03}}}$ $\newcommand {\bigcupplus }{\mathop {\unicode {x2A04}}}$ $\newcommand {\bigsqcap }{\mathop {\unicode {x2A05}}}$ $\newcommand {\bigtimes }{\mathop {\unicode {x2A09}}}$ $\let \varprod \bigtimes $ $\newcommand {\mappedfrom }{\mathrel {\unicode {x021A4}}}$ $\let \mappedfromchar \mappedfrom $ $\newcommand {\mapsfrom }{\mathrel {\unicode {x021A4}}}$ $\newcommand {\longmappedfrom }{\mathrel {\unicode {x027FB}}}$ $\newcommand {\Mapsto }{\mathrel {\unicode {x02907}}}$ $\let \Mapstochar \Mapsto $ $\newcommand {\Longmapsto }{\mathrel {\unicode {x027FE}}}$ $\newcommand {\Mappedfrom }{\mathrel {\unicode {x02906}}}$ $\let \Mappedfromchar \Mappedfrom $ $\newcommand {\Mapsfrom }{\mathrel {\unicode {x02906}}}$ $\newcommand {\Longmappedfrom }{\mathrel {\unicode {x27FD}}}$ $\newcommand {\medcirc }{\mathbin {\unicode {x025CB}}}$ $\newcommand {\medbullet }{\mathbin {\unicode {x025CF}}}$ $\newcommand {\varparallel }{\mathrel {\unicode {x02AFD}}}$ $\newcommand {\varparallelinv }{\mathrel {\unicode {x244A}}}$ $\newcommand {\nvarparallel }{\mathrel {\LWRoverlaysymbols {-}{\unicode {x02AFD}}}}$ $\newcommand {\nvarparallelinv }{\mathrel {\LWRoverlaysymbols {-}{\unicode {x244A}}}}$ $\newcommand {\coloneq }{\mathrel {\unicode {x02254}}}$ $\newcommand {\eqcolon }{\mathrel {\unicode {x02255}}}$ $\newcommand {\VDash }{\mathrel {\unicode {x22AB}}}$ $\newcommand {\preceqq }{\mathrel {\unicode {x02AB3}}}$ $\newcommand {\succeqq }{\mathrel {\unicode {x02AB4}}}$ $\newcommand {\nprecsim }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0227E}}}}$ $\newcommand {\nsuccsim }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0227F}}}}$ $\newcommand {\nlesssim }{\mathrel {\unicode {x02274}}}$ $\newcommand {\ngtrsim }{\mathrel {\unicode {x02275}}}$ $\newcommand {\nsubset }{\mathrel {\unicode {x02284}}}$ $\newcommand {\nsupset }{\mathrel {\unicode {x02285}}}$ $\newcommand {\notni }{\mathrel {\unicode {x220C}}}$ $\let \notowns \notni $ $\newcommand {\nlessapprox }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x02A85}}}}$ $\newcommand {\ngtrapprox }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x02A86}}}}$ $\newcommand {\npreccurlyeq }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0227C}}}}$ $\newcommand {\nsucccurlyeq }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0227D}}}}$ $\newcommand {\ngtrless }{\mathrel {\unicode {x02279}}}$ $\newcommand {\nlessgtr }{\mathrel {\unicode {x2278}}}$ $\newcommand {\nbumpeq }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0224F}}}}$ $\newcommand {\nBumpeq }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0224E}}}}$ $\newcommand {\nbacksim }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0223D}}}}$ $\newcommand {\nbacksimeq }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x022CD}}}}$ $\newcommand {\nasymp }{\mathrel {\unicode {x226D}}}$ $\newcommand {\nequiv }{\mathrel {\unicode {x2262}}}$ $\newcommand {\napprox }{\mathrel {\unicode {x2249}}}$ $\newcommand {\nll }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0226A}}}}$ $\newcommand {\ngg }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0226B}}}}$ $\newcommand {\nthickapprox }{\mathrel {\LWRoverlaysymbols {/}{{\mathbf {\unicode {x02248}}}}}}$ $\newcommand {\napproxeq }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0224A}}}}$ $\newcommand {\nprecapprox }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x02AB7}}}}$ $\newcommand {\nsuccapprox }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x02AB8}}}}$ $\newcommand {\npreceqq }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x02AB3}}}}$ $\newcommand {\nsucceqq }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x02AB4}}}}$ $\newcommand {\nsimeq }{\mathrel {\unicode {x02244}}}$ $\newcommand {\nSubset }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x022D0}}}}$ $\newcommand {\nSupset }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x022D1}}}}$ $\newcommand {\nsqsubseteq }{\mathrel {\unicode {x022E2}}}$ $\newcommand {\nsqsupseteq }{\mathrel {\unicode {x022E3}}}$ $\newcommand {\coloneqq }{\mathrel {\unicode {x02254}}}$ $\newcommand {\eqqcolon }{\mathrel {\unicode {x02255}}}$ $\newcommand {\Coloneqq }{\mathrel {\unicode {x02A74}}}$ $\newcommand {\Coloneq }{\mathrel {\unicode {x2237}-}}$ $\newcommand {\Eqcolon }{\mathrel {-\unicode {x2237}}}$ $\newcommand {\lvec }[1]{\mathord {\overset {\unicode {x02190}}{#1}}}$ $\newcommand {\lrvec }[1]{\mathord {\overset {\unicode {x2194}}{#1}}}$ $\newcommand {\harpoonacc }[1]{\mathord {\overset {\unicode {x021C0}}{#1}}}$ $\newcommand {\lharpoonacc }[1]{\mathord {\overset {\unicode {x021BC}}{#1}}}$ $\newcommand {\lrharpoonacc }[1]{\mathord {\overset {\unicode {x0294E}}{#1}}}$ $\newcommand {\barbar }[1]{\mathord {\overset {=}{#1}}}$ $\newcommand {\bartilde }[1]{\mathord {\overset {\simeq }{#1}}}$ $\newcommand {\barhat }[1]{\mathord {\hat {\bar {#1}}}}$ $\newcommand {\tildebar }[1]{\mathord {\overset {\eqsim }{#1}}}$ $\newcommand {\tildetilde }[1]{\mathord {\overset {\approx }{#1}}}$ $\newcommand {\tildehat }[1]{\mathord {\hat {\tilde {#1}}}}$ $\newcommand {\hatbar }[1]{\mathord {\bar {\hat {#1}}}}$ $\newcommand {\hattilde }[1]{\mathord {\tilde {\hat {#1}}}}$ $\newcommand {\hathat }[1]{\mathord {\hat {\hat {#1}}}}$ $\newcommand {\cdotB }{\mathord {\boldsymbol {\cdot }}}$ $\newcommand {\cdotBB }{\mathord {\unicode {x2022}}}$ $\newcommand {\circS }{\boldsymbol {\circ }}$ $\newcommand {\bulletSSS }{\bullet }$ $\newcommand {\bulletSS }{\mathord {\unicode {x025CF}}}$ $\newcommand {\bulletS }{\mathord {\unicode {x02B24}}}$ $\newcommand {\primeS }{\prime }$ $\newcommand {\invamp }{\mathbin {\unicode {x0214B}}}$ $\newcommand {\Lbag }{\mathopen {\large \unicode {x027C5}}}$ $\newcommand {\Rbag }{\mathclose {\large \unicode {x027C6}}}$ $\newcommand {\circledless }{\mathrel {\unicode {x029C0}}}$ $\newcommand {\circledgtr }{\mathrel {\unicode {x029C1}}}$ $\newcommand {\circledbslash }{\mathbin {\unicode {x029B8}}}$ $\newcommand {\lJoin }{\mathrel {\unicode {x22C9}}}$ $\newcommand {\rJoin }{\mathrel {\unicode {x22CA}}}$ $\newcommand {\lrJoin }{\mathrel {\unicode {x2A1D}}}$ $\newcommand {\lrtimes }{\mathrel {\unicode {x2A1D}}}$ $\newcommand {\Diamondblack }{\mathord {\unicode {x025C6}}}$ $\newcommand {\nplus }{\mathrel {\LWRoverlaysymbols {+}{\unicode {x02229}}}}$ $\newcommand {\nsqsubset }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x0228F}}}}$ $\newcommand {\nsqsupset }{\mathrel {\LWRoverlaysymbols {/}{\unicode {x02290}}}}$ $\newcommand {\dasharrow }{\mathrel {\unicode {x021E2}}}$ $\newcommand {\leftsquigarrow }{\mathrel {\unicode {x021DC}}}$ $\newcommand {\ntwoheadrightarrow }{\mathrel {\unicode {x02900}}}$ $\newcommand {\ntwoheadleftarrow }{\mathrel {\unicode {x02B34}}}$ $\newcommand {\boxast }{\mathbin {\unicode {x029C6}}}$ $\newcommand {\boxbslash }{\mathbin {\unicode {x29C5}}}$ $\newcommand {\boxbar }{\mathbin {\unicode {x025EB}}}$ $\newcommand {\boxslash }{\mathbin {\unicode {x029C4}}}$ $\newcommand {\varclubsuit }{\mathord {\unicode {x02667}}}$ $\newcommand {\vardiamondsuit }{\mathord {\unicode {x02666}}}$ $\newcommand {\varheartsuit }{\mathord {\unicode {x02665}}}$ $\newcommand {\varspadesuit }{\mathord {\unicode {x02664}}}$ $\newcommand {\Nearrow }{\mathrel {\unicode {x021D7}}}$ $\newcommand {\Searrow }{\mathrel {\unicode {x021D8}}}$ $\newcommand {\Nwarrow }{\mathrel {\unicode {x021D6}}}$ $\newcommand {\Swarrow }{\mathrel {\unicode {x021D9}}}$ $\newcommand {\Top }{\mathord {\unicode {x02AEA}}}$ $\newcommand {\Bot }{\mathord {\unicode {x02AEB}}}$ $\newcommand {\leadstoext }{\mathrel {\unicode {xFF5E}}}$ $\newcommand {\sqcupplus }{\mathbin {\LWRoverlaysymbols {+}{\unicode {x02294}}}}$ $\newcommand {\sqcapplus }{\mathbin {\LWRoverlaysymbols {+}{\unicode {x02293}}}}$ $\newcommand {\dlb }{\mathopen {\unicode {x027E6}}}$ $\newcommand {\drb }{\mathopen {\unicode {x027E7}}}$ $\newcommand {\varg }{g}$ $\newcommand {\vary }{y}$ $\newcommand {\varv }{v}$ $\newcommand {\varw }{w}$ $\newcommand {\nexistsAlt }{\mathord {\unicode {x02204}}}$ $\newcommand {\existsAlt }{\mathord {\unicode {x02203}}}$ $\newcommand {\forallAlt }{\mathord {\unicode {x02200}}}$ $\newcommand {\emptysetAlt }{\mathord {\unicode {x02205}}}$ $\newcommand {\uppartial }{\mathord {\unicode {x02202}}}$ $\let \varmathbb \mathbb $ $\let \vmathbb \mathbb $ $\let \vvmathbb \mathbb $ $\let \smallprod \prod $ $\let \smallsum \sum $ $\let \smallcoprod \coprod $ $\newcommand {\openbox }{\mathord {\unicode {x25FD}}}$ $\let \textsquare \openbox $ $\let \varemptyset \emptyset $ $\newcommand {\mathsterling }{\mathord {\unicode {x000A3}}}$ $\newcommand {\mathcent }{\mathord {\unicode {x000A2}}}$ $\def\Alphaup{\unicode{x0391}}$ $\def\Betaup{\unicode{x0392}}$ $\def\Gammaup{\unicode{x0393}}$ $\def\Digammaup{\unicode{x03DC}}$ $\def\Deltaup{\unicode{x0394}}$ $\def\Epsilonup{\unicode{x0395}}$ $\def\Zetaup{\unicode{x0396}}$ $\def\Etaup{\unicode{x0397}}$ $\def\Thetaup{\unicode{x0398}}$ $\def\Varthetaup{\unicode{x03F4}}$ $\def\Iotaup{\unicode{x0399}}$ $\def\Kappaup{\unicode{x039A}}$ $\def\Lambdaup{\unicode{x039B}}$ $\def\Muup{\unicode{x039C}}$ $\def\Nuup{\unicode{x039D}}$ $\def\Xiup{\unicode{x039E}}$ $\def\Omicronup{\unicode{x039F}}$ $\def\Piup{\unicode{x03A0}}$ $\def\Varpiup{\unicode{x03D6}}$ $\def\Rhoup{\unicode{x03A1}}$ $\def\Sigmaup{\unicode{x03A3}}$ $\def\Tauup{\unicode{x03A4}}$ $\def\Upsilonup{\unicode{x03A5}}$ $\def\Phiup{\unicode{x03A6}}$ $\def\Chiup{\unicode{x03A7}}$ $\def\Psiup{\unicode{x03A8}}$ $\def\Omegaup{\unicode{x03A9}}$ $\def\upAlpha{\unicode{x0391}}$ $\def\upBeta{\unicode{x0392}}$ $\def\upGamma{\unicode{x0393}}$ $\def\upDigamma{\unicode{x03DC}}$ $\def\upDelta{\unicode{x0394}}$ $\def\upEpsilon{\unicode{x0395}}$ $\def\upZeta{\unicode{x0396}}$ $\def\upEta{\unicode{x0397}}$ $\def\upTheta{\unicode{x0398}}$ $\def\upVartheta{\unicode{x03F4}}$ $\def\upIota{\unicode{x0399}}$ $\def\upKappa{\unicode{x039A}}$ $\def\upLambda{\unicode{x039B}}$ $\def\upMu{\unicode{x039C}}$ $\def\upNu{\unicode{x039D}}$ $\def\upXi{\unicode{x039E}}$ $\def\upOmicron{\unicode{x039F}}$ $\def\upPi{\unicode{x03A0}}$ $\def\upVarpi{\unicode{x03D6}}$ $\def\upRho{\unicode{x03A1}}$ $\def\upSigma{\unicode{x03A3}}$ $\def\upTau{\unicode{x03A4}}$ $\def\upUpsilon{\unicode{x03A5}}$ $\def\upPhi{\unicode{x03A6}}$ $\def\upChi{\unicode{x03A7}}$ $\def\upPsi{\unicode{x03A8}}$ $\def\upOmega{\unicode{x03A9}}$ $\def\upalpha{\unicode{x03B1}}$ $\def\upbeta{\unicode{x03B2}}$ $\def\upvarbeta{\unicode{x03D0}}$ $\def\upgamma{\unicode{x03B3}}$ $\def\updigamma{\unicode{x03DD}}$ $\def\updelta{\unicode{x03B4}}$ $\def\upepsilon{\unicode{x03F5}}$ $\def\upvarepsilon{\unicode{x03B5}}$ $\def\upzeta{\unicode{x03B6}}$ $\def\upeta{\unicode{x03B7}}$ $\def\uptheta{\unicode{x03B8}}$ $\def\upvartheta{\unicode{x03D1}}$ $\def\upiota{\unicode{x03B9}}$ $\def\upkappa{\unicode{x03BA}}$ $\def\upvarkappa{\unicode{x03F0}}$ $\def\uplambda{\unicode{x03BB}}$ $\def\upmu{\unicode{x03BC}}$ $\def\upnu{\unicode{x03BD}}$ $\def\upxi{\unicode{x03BE}}$ $\def\upomicron{\unicode{x03BF}}$ $\def\uppi{\unicode{x03C0}}$ $\def\upvarpi{\unicode{x03D6}}$ $\def\uprho{\unicode{x03C1}}$ $\def\upvarrho{\unicode{x03F1}}$ $\def\upsigma{\unicode{x03C3}}$ $\def\upvarsigma{\unicode{x03C2}}$ $\def\uptau{\unicode{x03C4}}$ $\def\upupsilon{\unicode{x03C5}}$ $\def\upphi{\unicode{x03D5}}$ $\def\upvarphi{\unicode{x03C6}}$ $\def\upchi{\unicode{x03C7}}$ $\def\uppsi{\unicode{x03C8}}$ $\def\upomega{\unicode{x03C9}}$ $\def\alphaup{\unicode{x03B1}}$ $\def\betaup{\unicode{x03B2}}$ $\def\varbetaup{\unicode{x03D0}}$ $\def\gammaup{\unicode{x03B3}}$ $\def\digammaup{\unicode{x03DD}}$ $\def\deltaup{\unicode{x03B4}}$ $\def\epsilonup{\unicode{x03F5}}$ $\def\varepsilonup{\unicode{x03B5}}$ $\def\zetaup{\unicode{x03B6}}$ $\def\etaup{\unicode{x03B7}}$ $\def\thetaup{\unicode{x03B8}}$ $\def\varthetaup{\unicode{x03D1}}$ $\def\iotaup{\unicode{x03B9}}$ $\def\kappaup{\unicode{x03BA}}$ $\def\varkappaup{\unicode{x03F0}}$ $\def\lambdaup{\unicode{x03BB}}$ $\def\muup{\unicode{x03BC}}$ $\def\nuup{\unicode{x03BD}}$ $\def\xiup{\unicode{x03BE}}$ $\def\omicronup{\unicode{x03BF}}$ $\def\piup{\unicode{x03C0}}$ $\def\varpiup{\unicode{x03D6}}$ $\def\rhoup{\unicode{x03C1}}$ $\def\varrhoup{\unicode{x03F1}}$ $\def\sigmaup{\unicode{x03C3}}$ $\def\varsigmaup{\unicode{x03C2}}$ $\def\tauup{\unicode{x03C4}}$ $\def\upsilonup{\unicode{x03C5}}$ $\def\phiup{\unicode{x03D5}}$ $\def\varphiup{\unicode{x03C6}}$ $\def\chiup{\unicode{x03C7}}$ $\def\psiup{\unicode{x03C8}}$ $\def\omegaup{\unicode{x03C9}}$ $\def\Alphait{\unicode{x1D6E2}}$ $\def\Betait{\unicode{x1D6E3}}$ $\def\Gammait{\unicode{x1D6E4}}$ $\def\Digammait{\mathit{\unicode{x03DC}}}$ $\def\Deltait{\unicode{x1D6E5}}$ $\def\Epsilonit{\unicode{x1D6E6}}$ $\def\Zetait{\unicode{x1D6E7}}$ $\def\Etait{\unicode{x1D6E8}}$ $\def\Thetait{\unicode{x1D6E9}}$ $\def\Varthetait{\unicode{x1D6F3}}$ $\def\Iotait{\unicode{x1D6EA}}$ $\def\Kappait{\unicode{x1D6EB}}$ $\def\Lambdait{\unicode{x1D6EC}}$ $\def\Muit{\unicode{x1D6ED}}$ $\def\Nuit{\unicode{x1D6EE}}$ $\def\Xiit{\unicode{x1D6EF}}$ $\def\Omicronit{\unicode{x1D6F0}}$ $\def\Piit{\unicode{x1D6F1}}$ $\def\Rhoit{\unicode{x1D6F2}}$ $\def\Sigmait{\unicode{x1D6F4}}$ $\def\Tauit{\unicode{x1D6F5}}$ $\def\Upsilonit{\unicode{x1D6F6}}$ $\def\Phiit{\unicode{x1D6F7}}$ $\def\Chiit{\unicode{x1D6F8}}$ $\def\Psiit{\unicode{x1D6F9}}$ $\def\Omegait{\unicode{x1D6FA}}$ $\def\alphait{\unicode{x1D6FC}}$ $\def\betait{\unicode{x1D6FD}}$ $\def\varbetait{\unicode{x03D0}}$ $\def\gammait{\unicode{x1D6FE}}$ $\def\digammait{\mathit{\unicode{x03DD}}}$ $\def\deltait{\unicode{x1D6FF}}$ $\def\epsilonit{\unicode{x1D716}}$ $\def\varepsilonit{\unicode{x1D700}}$ $\def\zetait{\unicode{x1D701}}$ $\def\etait{\unicode{x1D702}}$ $\def\thetait{\unicode{x1D703}}$ $\def\varthetait{\unicode{x1D717}}$ $\def\iotait{\unicode{x1D704}}$ $\def\kappait{\unicode{x1D705}}$ $\def\varkappait{\unicode{x1D718}}$ $\def\lambdait{\unicode{x1D706}}$ $\def\muit{\unicode{x1D707}}$ $\def\nuit{\unicode{x1D708}}$ $\def\xiit{\unicode{x1D709}}$ $\def\omicronit{\unicode{x1D70A}}$ $\def\piit{\unicode{x1D70B}}$ $\def\varpiit{\unicode{x1D71B}}$ $\def\rhoit{\unicode{x1D70C}}$ $\def\varrhoit{\unicode{x1D71A}}$ $\def\sigmait{\unicode{x1D70E}}$ $\def\varsigmait{\unicode{x1D70D}}$ $\def\tauit{\unicode{x1D70F}}$ $\def\upsilonit{\unicode{x1D710}}$ $\def\phiit{\unicode{x1D719}}$ $\def\varphiit{\unicode{x1D711}}$ $\def\chiit{\unicode{x1D712}}$ $\def\psiit{\unicode{x1D713}}$ $\def\omegait{\unicode{x1D714}}$ $\def\itAlpha{\unicode{x1D6E2}}$ $\def\itBeta{\unicode{x1D6E3}}$ $\def\itGamma{\unicode{x1D6E4}}$ $\def\itDigamma{\mathit{\unicode{x03DC}}}$ $\def\itDelta{\unicode{x1D6E5}}$ $\def\itEpsilon{\unicode{x1D6E6}}$ $\def\itZeta{\unicode{x1D6E7}}$ $\def\itEta{\unicode{x1D6E8}}$ $\def\itTheta{\unicode{x1D6E9}}$ $\def\itVartheta{\unicode{x1D6F3}}$ $\def\itIota{\unicode{x1D6EA}}$ $\def\itKappa{\unicode{x1D6EB}}$ $\def\itLambda{\unicode{x1D6EC}}$ $\def\itMu{\unicode{x1D6ED}}$ $\def\itNu{\unicode{x1D6EE}}$ $\def\itXi{\unicode{x1D6EF}}$ $\def\itOmicron{\unicode{x1D6F0}}$ $\def\itPi{\unicode{x1D6F1}}$ $\def\itRho{\unicode{x1D6F2}}$ $\def\itSigma{\unicode{x1D6F4}}$ $\def\itTau{\unicode{x1D6F5}}$ $\def\itUpsilon{\unicode{x1D6F6}}$ $\def\itPhi{\unicode{x1D6F7}}$ $\def\itChi{\unicode{x1D6F8}}$ $\def\itPsi{\unicode{x1D6F9}}$ $\def\itOmega{\unicode{x1D6FA}}$ $\def\italpha{\unicode{x1D6FC}}$ $\def\itbeta{\unicode{x1D6FD}}$ $\def\itvarbeta{\unicode{x03D0}}$ $\def\itgamma{\unicode{x1D6FE}}$ $\def\itdigamma{\mathit{\unicode{x03DD}}}$ $\def\itdelta{\unicode{x1D6FF}}$ $\def\itepsilon{\unicode{x1D716}}$ $\def\itvarepsilon{\unicode{x1D700}}$ $\def\itzeta{\unicode{x1D701}}$ $\def\iteta{\unicode{x1D702}}$ $\def\ittheta{\unicode{x1D703}}$ $\def\itvartheta{\unicode{x1D717}}$ $\def\itiota{\unicode{x1D704}}$ $\def\itkappa{\unicode{x1D705}}$ $\def\itvarkappa{\unicode{x1D718}}$ $\def\itlambda{\unicode{x1D706}}$ $\def\itmu{\unicode{x1D707}}$ $\def\itnu{\unicode{x1D708}}$ $\def\itxi{\unicode{x1D709}}$ $\def\itomicron{\unicode{x1D70A}}$ $\def\itpi{\unicode{x1D70B}}$ $\def\itvarpi{\unicode{x1D71B}}$ $\def\itrho{\unicode{x1D70C}}$ $\def\itvarrho{\unicode{x1D71A}}$ $\def\itsigma{\unicode{x1D70E}}$ $\def\itvarsigma{\unicode{x1D70D}}$ $\def\ittau{\unicode{x1D70F}}$ $\def\itupsilon{\unicode{x1D710}}$ $\def\itphi{\unicode{x1D719}}$ $\def\itvarphi{\unicode{x1D711}}$ $\def\itchi{\unicode{x1D712}}$ $\def\itpsi{\unicode{x1D713}}$ $\def\itomega{\unicode{x1D714}}$ $\newcommand{\anglesLWRsubstar}[2][]{{#1\left \langle #2#1\right \rangle }}$ $\newcommand{\anglesLWRsubnostar}[2][]{{#1\langle #2#1\rangle }}$ $\newcommand{\angles}{\ifstar\anglesLWRsubstar\anglesLWRsubnostar}$

4Examples¶

Below are a few diagrams which demonstrate how the package can be used in some more practical examples..

Vertex Rule: \feynmandiagram [ horizontal=a to b] { a [ particle=$Z$] -- [ photon, momentum=$p_{1}$] b, f1 [ particle=$\overline f$] -- [ fermion, rmomentum'=$p_{3}$] b -- [ fermion, momentum=$p_{2}$] f2 [ particle=$f$], };
Tree Level Diagrams: \feynmandiagram [ horizontal=a to b] { i1 [ particle=$e^{-}$] -- [ fermion] a -- [ fermion] i2 [ particle=$e^{+}$], a -- [ photon, edge label=$\gamma$] b, f1 [ particle=$\mu^{-}$] -- [ fermion] b -- [ fermion] f2 [ particle=$\mu^{+}$], };

\feynmandiagram [ vertical'=a to b] { i1 [ particle=$e^{-}$] -- [ fermion] a -- [ fermion] f1 [ particle=$e^{-}$], a -- [ photon, edge label=$\gamma$] b, i2 [ particle=$e^{+}$] -- [ anti fermion] b -- [ anti fermion] f2 [ particle=$e^{+}$], };

\begin{tikzpicture} \begin{ feynman} \diagram [ vertical'=a to b] { i1 [ particle=$e^{-}$] -- [ fermion] a -- [draw=none] f1 [ particle=$e^{+}$], a -- [ photon, edge label'=$p$] b, i2 [ particle=$e^{+}$] -- [ anti fermion] b -- [draw=none] f2 [ particle=$e^{-}$], }; \diagram* { (a) -- [ fermion] (f2), (b) -- [ anti fermion] (f1), }; \end{ feynman} \end{tikzpicture}
Loops: \feynmandiagram [ layered layout, horizontal=b to c] { a -- [ photon, momentum=$p$] b -- [ fermion, half left, momentum=$k$] c -- [ fermion, half left, momentum=$k-p$] b, c -- [ photon, momentum=$p$] d, };

\feynmandiagram [ layered layout, horizontal=a to b] [ edges= gluon] { {i1, i2} -- a -- [ half left] b -- [ half left] a, b -- {f1, f2}, };
Box Diagrams: \feynmandiagram [ layered layout, horizontal=a to b] { % Draw the top and bottom lines i1 [ particle=$d$] -- [ fermion] a -- [ photon, edge label=$W^{-}$] b -- [ fermion] f1 [ particle=$\mu^{-}$], i2 [ particle=$\overline s$] -- [ anti fermion] c -- [ photon, edge label'=$W^{+}$] d -- [ anti fermion] f2 [ particle=$\mu^{+}$], % Draw the two internal fermion lines { [same layer] a -- [ fermion, edge label'=$q$] c }, { [same layer] b -- [ anti fermion, edge label=$\nu_{\mu}$] d}, };
Meson decay and mixing: \begin{tikzpicture} \begin{ feynman} \vertex (a1) {$\overline b$}; \vertex[right=1.5cm of a1] (a2); \vertex[right=1cm of a2] (a3); \vertex[right=1.5cm of a3] (a4) {$\overline u$}; \vertex[below=2em of a1] (b1) {$d$}; \vertex[below=2em of a4] (b2) {$d$}; %% See section 13.5 of PGF/TikZ manual \vertex at ($(a2)!0.5!(a3)!0.5cm!90:(a3)$) (d); %% Equivalent way to obtain (d): % \vertex at ($(b2)!0.5!(b3) + (0, -0.5cm)$) (d); \vertex[above=of a4] (c1) {$u$}; \vertex[above=2em of c1] (c3) {$\overline d$}; \vertex at ($(c1)!0.5!(c3) - (1cm, 0)$) (c2); \diagram* { (a4) -- [ fermion] (a3) -- [ fermion] (a2) -- [ fermion] (a1), (b1) -- [ fermion] (b2), (c3) -- [ fermion, out=180, in=45] (c2) -- [ fermion, out=-45, in=180] (c1), (a2) -- [ boson, quarter left] (d) -- [ boson, quarter left] (a3), (d) -- [ boson, bend left, edge label=$W^{+}$] (c2), }; \draw [decoration={brace}, decorate] (b1.south west) -- (a1.north west) node [pos=0.5, left] {$B^{0}$}; \draw [decoration={brace}, decorate] (c3.north east) -- (c1.south east) node [pos=0.5, right] {$\pi^{+}$}; \draw [decoration={brace}, decorate] (a4.north east) -- (b2.south east) node [pos=0.5, right] {$\pi^{-}$}; \end{ feynman} \end{tikzpicture}

\begin{tikzpicture} \begin{ feynman} \vertex (a1) {$\overline b$}; \vertex[right=1cm of a1] (a2); \vertex[right=1cm of a2] (a3); \vertex[right=1cm of a3] (a4) {$b$}; \vertex[right=1cm of a4] (a5); \vertex[right=2cm of a5] (a6) {$u$}; \vertex[below=2em of a1] (b1) {$d$}; \vertex[right=1cm of b1] (b2); \vertex[right=1cm of b2] (b3); \vertex[right=1cm of b3] (b4) {$\overline d$}; \vertex[below=2em of a6] (b5) {$\overline d$}; \vertex[above=of a6] (c1) {$\overline u$}; \vertex[above=2em of c1] (c3) {$d$}; \vertex at ($(c1)!0.5!(c3) - (1cm, 0)$) (c2); \diagram* { {[ edges= fermion] (b1) -- (b2) -- (a2) -- (a1), (b5) -- (b4) -- (b3) -- (a3) -- (a4) -- (a5) -- (a6), }, (a2) -- [ boson, edge label=$W$] (a3), (b2) -- [ boson, edge label'=$W$] (b3), (c1) -- [ fermion, out=180, in=-45] (c2) -- [ fermion, out=45, in=180] (c3), (a5) -- [ boson, bend left, edge label=$W^{-}$] (c2), }; \draw [decoration={brace}, decorate] (b1.south west) -- (a1.north west) node [pos=0.5, left] {$B^{0}$}; \draw [decoration={brace}, decorate] (c3.north east) -- (c1.south east) node [pos=0.5, right] {$\pi^{-}$}; \draw [decoration={brace}, decorate] (a6.north east) -- (b5.south east) node [pos=0.5, right] {$\pi^{+}$}; \end{ feynman} \end{tikzpicture}

\begin{tikzpicture} \begin{ feynman} \vertex (a1) {$\overline b$}; \vertex[right=2cm of a1] (a2); \vertex[right=0.5cm of a2] (a3); \vertex[right=0.5cm of a3] (a4); \vertex[right=2cm of a4] (a5) {$\overline s$}; \vertex[below=2cm of a1] (b1) {$d$}; \vertex[below=2cm of a5] (b2) {$d$}; \vertex[below=1.5em of a5] (c1) {$s$}; \vertex[above=1.5em of b2] (c3) {$\overline s$}; \vertex at ($(c1)!0.5!(c3) - (1cm, 0)$) (c2); \diagram* { {[ edges= fermion] (a5) -- (a4) -- (a3) -- (a2) -- (a1), }, (b1) -- [ fermion] (b2), (c3) -- [ fermion, out=180, in=-60] (c2) -- [ fermion, out=60, in=180] (c1), (a3) -- [ gluon, bend right] (c2), (a4) -- [ boson, out=90, in=90, looseness=2.0, edge label'=$W^{+}$] (a2) }; \draw [decoration={brace}, decorate] (b1.south west) -- (a1.north west) node [pos=0.5, left] {$B^{0}$}; \draw [decoration={brace}, decorate] (a5.north east) -- (c1.south east) node [pos=0.5, right] {$\phi$}; \draw [decoration={brace}, decorate] (c3.north east) -- (b2.south east) node [pos=0.5, right] {$K^{0}$}; \end{ feynman} \end{tikzpicture}