Changes between Version 8 and Version 9 of TechniColor

11/26/10 20:54:16 (10 years ago)



  • TechniColor

    v8 v9  
    1111   * [ Claudio Pica] ( pica @ )
     13Jeppe R. Andersen, Oleg Antipin and Marco Nardecchia helped in the validation.
    1315An earlier implementation of this model on LanHEP was written by M. Frandsen, R. Foadi, M. Järvinen.
    1719=== Description of the model ===
     21__Official page__: [].
    1923We have implemented the simplest of the recently identified walking technicolor models, which can pass the electroweak precision tests.
    3034The most relevant references for this model implementation are:
    3136    * Phys. Rev. D 71, 051901 (2005) [] - F. Sannino and K. Tuominen, ''Orientifold Theory Dynamics and Symmetry Breaking''. Note that the original name was ''Techniorientifold''.
    3237    * Phys. Rev. D 76, 055005 ( 2007) [] - R. Foadi, M.T. Frandsen, T. A. Ryttov, F. Sannino, ''Minimal Walking Technicolor: Set Up for Collider Physics''. This article derives the effective theory for MWT.
    3540See also:
    3642    * Phys. Lett. B597:89-93,2004 [] - Deog Ki Hong, Stephen D.H. Hsu, F. Sannino, ''Composite Higgs from higher representations''.
    3743    * Phys. Rev. D72:055001, 2005 []  - D.D. Dietrich, F. Sannino, K. Tuominen ''Light composite Higgs from higher representations versus electroweak precision measurements: Predictions for CERN LHC''.
    6975In addition to the standard model fermions, we thus have the following new particles:
    7077* Composite Higgs scalar H
    7178* Neutral heavy vector R,,1,,^0^
    72 * Charged heavy vector R,,1,,^+^, R,,1,,^-^
     79* Charged heavy vectors R,,1,,^+^, R,,1,,^-^
    7380* Neutral heavy vector R,,2,,^0^
    74 * Charged heavy vector R,,2,,^+^, R,,2,,^-^
     81* Charged heavy vectors R,,2,,^+^, R,,2,,^-^
    7683The numbering convention for the heavy spin-one states is such that R,,1,, is always the lighter one. When the mass scale is below 1 TeV R,,1,, (R,,2,,) has larger component of the axial (vector) spin-one composite state than of the vector (axial) state. When masses are increased to about 2 TeV, the situation is reversed.
    7885Using the effective theory introduces several new coupling constants. These can be constrained by linking to the underlying gauge theory via the Weinberg sum rules and the definition of the electroweak S parameter. After taking into account the Weinberg sum rules, the free parameters can be expressed in terms of:
    7987* MA: The spin-one mass scale. More precisely, the mass of the axial spin-one state in the limit where the electroweak interactions are turned off. Allowed range is from about 500 GeV to about 3 TeV, depending on the values of other parameters.
    8088* gt: The effective strength of technicolor interactions. Parametrizes the corrections of the electroweak interactions to the technicolor sector, which are typically O(g/gt), with g being the weak coupling constant. In particular, the mixing of the composite spin-one states with the electroweak gauge bosons, and therefore also the coupling of the composite spin-one states to the standard model fermions, is O(g/gt). Allowed values range from about 1 to about 10.
    9199The implementation of the following MWTC processes through the FeynRules interface was cross-checked with the already existing implementation in LanHEP (see references):
    92101  * pp > jj at 1400 GeV
    93102  * pp > mu+mu- at 1400 GeV
    94104Furthermore, the matrix element generated for qq~>mu+mu- was checked by hand for a few phase space points.