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5Â¥2010-06-08 21:47:56
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Сľ³æ:)(½ð±Ò+2):»¹Êǽ¨ÒéÄúÓúºÓï 2010-06-07 23:34:19
Your Feynman diagram is OK.
As for the invariant matrix element, there is a complex number "i" missing in the 1st line while a "\sum" is lost in the second line.
If you wanna further calculations of this cross section, analyse the kinematics in the center of mass frame and then integrate over the whole phase space. This is a 2 to 2 process. We can do it by hand easily. I will show my calculations tonight if I have free time.

Good luck.
2Â¥2010-06-07 17:31:06
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