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View some example FeynWeb diagrams, along with their XML code, to give you an idea of what is possible and to help you get started.

e+ e- scattering

A very simple example showing electron-positron elastic scattering. Demonstrates basic usage of vertices and particles.

1. <feynweb height="300px" width="700px" stylesheet="style_default.fws">
2. <input id="i1" x="100" y="50"> <label position="w">e+</label> </input>
3. <input id="i2" x="100" y="250"> <label position="w">e-</label> </input>
4. <vertex id="v1" x="250" y="150" />
5. <vertex id="v2" x="450" y="150" />
6. <output id="o1" x="600" y="50"> <label position="e">e+</label> </output>
7. <output id="o2" x="600" y="250"> <label position="e">e-</label> </output>
8. <fermion id="eplus1" start="v1" end="i1"> <arrow /> </fermion>
9. <fermion id="eminus1" start="i2" end="v1"> <arrow /> </fermion>
10. <photon id="gamma1" start="v1" end="v2"> <label position="n">&gamma;</label> </photon>
11. <fermion id="eplus2" start="o1" end="v2"> <arrow /> </fermion>
12. <fermion id="eminus2" start="v2" end="o2"> <arrow /> </fermion>
13. </feynweb>

OZI Diagram

A more complicated example showing the OZI-suppressed decay of the J/ψ to 3 pions. Demonstrates the grouping of vertices into mesons and the ability to control the spin direction of gluons.

Note that labels may not be displayed well: see the known issues for the current release.

1. <feynweb height="400px" width="700px" stylesheet="style_default.fws">
2. <!-- Initial J/Psis-->
3. <nodegroup x="100" y="200" nodegroup-separation="70">
4. <input id="vc1" type="none">
5. <label position="c">c</label>
6. </input>
7. <input id="vc5" type="none">
8. <label position="c" text-decoration="overline">c</label>
9. </input>
10. <label position="w" r="40">J/&psi;</label>
11. </nodegroup>
12. <!-- The charm-quark loop vertices -->
13. <vertex id="vc2" x="250" y="150" />
14. <vertex id="vc3" x="300" y="200" />
15. <vertex id="vc4" x="250" y="250" />
16. <!-- Central gluon decay vertices -->
17. <vertex id="top" x="500" y="135" />
18. <vertex id="mid" x="400" y="200" />
19. <vertex id="bot" x="500" y="265" />
20. <!-- The final Pions -->
21. <nodegroup x="600" y="75">
22. <output id="e1a" type="none">
23. <label position="c">u</label>
24. </output>
25. <output id="e1b" type="none">
26. <label position="c" text-decoration="overline">d</label>
27. </output>
28. <label position="e" r="40">&pi;<tspan baseline-shift="super">+</tspan></label>
29. </nodegroup>
30. <nodegroup x="600" y="200">
31. <output id="e2a" type="none">
32. <label position="c">d</label>
33. </output>
34. <output id="e2b" type="none">
35. <label position="c" text-decoration="overline">d</label>
36. </output>
37. <label position="e" r="40">&pi;<tspan baseline-shift="super">0</tspan></label>
38. </nodegroup>
39. <nodegroup x="600" y="325">
40. <output id="e3a" type="none">
41. <label position="c">d</label>
42. </output>
43. <output id="e3b" type="none">
44. <label position="c" text-decoration="overline">u</label>
45. </output>
46. <label position="e" r="40">&pi;<tspan baseline-shift="super">-</tspan></label>
47. </nodegroup>
48. <!-- Charm quarks -->
49. <fermion id="c1" start="vc1" end="vc2"> <arrow /> </fermion>
50. <fermion id="c2" start="vc2" end="vc3" />
51. <fermion id="c3" start="vc3" end="vc4" />
52. <fermion id="c4" start="vc4" end="vc5"> <arrow /> </fermion>
53. <!-- Intermediate gluons -->
54. <gluon id="g-top" start="vc2" end="top" />
55. <gluon id="g-mid" start="vc3" end="mid" />
56. <gluon id="g-bot" start="vc4" end="bot" spincw="0" />
57. <!-- Final quarks -->
58. <fermion id="q1a" start="mid" end="e1a" r="200" large="0"/>
59. <fermion id="q1b" start="top" end="e1b" />
60. <fermion id="q2a" start="top" end="e2a" />
61. <fermion id="q2b" start="bot" end="e2b" />
62. <fermion id="q3a" start="bot" end="e3a" />
63. <fermion id="q3b" start="mid" end="e3b" r="200" large="0" clockwise="0" />
64. </feynweb>