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| 3 | == ---+ Experimental tests of the spin of the top quark == |

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| 5 | ==== 1. ==== |

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| 7 | Compute analytically the partonic cross sections for %$q \bar q \to t \bar t$% and %$g g \to t \bar t$% for t spin 1/2 and spin 0 at the tree level. Check your results against the LO results available in the literature: |

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| 21 | ==== 2. ==== |

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| 23 | Consider the behaviour at threshold and also the relative sizes of the cross sections for corresponding masses. |

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| 25 | ==== 3. ==== |

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| 27 | Use any MC at tree level to calculate the cross sections for tops and stops at the Tevatron and the LHC. Make plots of the distributions and in particular of %$m_tt$%. |

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| 29 | ==== 4. ==== |

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| 31 | Compare your findings with [http://arxiv.org/abs/hep-ph/0002305 Top Spin and experimental tests], by Ed Berger and Tim Tait. |

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| 33 | -- Main.FabioMaltoni - 03 Dec 2008 |

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