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Nonstandard Higgs in Electroweak Chiral Lagrangian

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 نشر من قبل Wang Liming funicorn
 تاريخ النشر 2006
  مجال البحث
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We add a nonstandard higgs into the traditional bosonic part of electroweak chiral Lagrangian, in purpose of finding out the contribution to EWCL coefficients from processes with internal line higgs particle. To construct the effective Lagrangian with higgs, we use low energy expansion scheme and write down all the independent terms conserving $SU(2)times U_Y(1)$ symmetry in the nonlinear representation which we show is equivalent to the linear representation. Then we integrate out higgs using loop expansion technique at 1-loop level, contributions from all possible terms are obtained. We find three terms, $mathcal{L}_5$, $mathcal{L}_7$, $mathcal{L}_{10}$ in EWCL are important, for which the contributions from higgs can be further expressed in terms of higgs partial decay width $Gamma_{hto ZZ}$ and $Gamma_{hto WW}$. Higg mass dependence of the coefficients in EWCL are discussed.

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