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---
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title: Support of Dirac Gauginos
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permalink: /Support_of_Dirac_Gauginos/
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---
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[Category:Model](/Category:Model "wikilink") Another feature which became popular in the last years are models with Dirac gauginos. In these models mass terms*m*<sub>*D*</sub><sup>*ϕ̂*<sub>*i*</sub>*A*</sup>*λ*<sub>*A*</sub>*ψ*<sub>*i*</sub> between gauginos*λ*<sub>*A*</sub> and a fermionic component*ψ*<sub>*i*</sub> of the chiral superfield*ϕ̂*<sub>*i*</sub> in the adjoint representation of the gauge group*A* are present. In addition, also new*D*-terms are introduced in these models . Thus, the new terms in the Lagrangian are
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$\\mathfrak{L}_{DG} = - m^{\\hat \\phi_i A}_D \\lambda^a_A \\psi_i + \\sqrt{2} m^{\\hat \\phi_i A}_D \\phi_i D_A$
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*D*<sub>*A*</sub> is the auxiliary component of the vector superfield of the group*A*. To allow for Dirac mass terms, these models come always with an extended matter sector: to generate Dirac mass terms for all MSSM gauginos at least one singlet, one triplet under*S**U*(2) and one octet under*S**U*(3) must be added. Furthermore, models with Dirac gauginos generate also new structures in the RGEs . All of this is fully supported in SARAH.
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If Dirac masses for gauginos are explicitly turned on in SARAH, it will check for all allowed combinations of vector and chiral superfields which can generate Dirac masses and which are consistent with all symmetries. For instance, in models with several gauge singlets, the bino might even get several Dirac mass terms.
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### Superpotential, soft-terms and non-canonical interactions
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The matter interactions in SUSY models are usually fixed by the superpotential and the soft-SUSY breaking terms. SARAH fully supports all renormalizable terms in the superpotential
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*W* = *c*<sub>*L*</sub>*L*<sub>*i*</sub>*ϕ̂*<sub>*i*</sub> + *c*<sub>*M*</sub>*M*<sup>*i**j*</sup>*ϕ̂*<sub>*i*</sub>*ϕ̂*<sub>*j*</sub> + *c*<sub>*T*</sub>*Y*<sup>*i**j**k*</sup>*ϕ̂*<sub>*i*</sub>*ϕ̂*<sub>*j*</sub>*ϕ̂*<sub>*k*</sub>
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and generates the corresponding soft-breaking terms
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*L*<sub>*S**B*, *W*</sub> = *c*<sub>*L*</sub>*t*<sub>*i*</sub>*ϕ*<sub>*i*</sub> + *c*<sub>*M*</sub>*B*<sup>*i**j*</sup>*ϕ*<sub>*i*</sub>*ϕ*<sub>*j*</sub> + *c*<sub>*T*</sub>*T*<sup>*i**j**k*</sup>*ϕ*<sub>*i*</sub>*ϕ*<sub>*j*</sub>*ϕ*<sub>*k*</sub> + *h*.*c*.
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*c*<sub>*L*</sub>,*c*<sub>*M*</sub>,*c*<sub>*T*</sub> are real coefficients. All parameters are treated by default in the most general way by taking them as complex tensors of appropriate order and dimension. If identical fields are involved in the same coupling, SARAH derives also the symmetry properties for the parameter.
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As discussed below, SARAH can also handle to some extent non-renormalizable terms with four superfields in the superpotential
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*W*<sub>*N**R*</sub> = *c*<sub>*W*</sub>*W*<sup>*i**j**k**l*</sup>*ϕ̂*<sub>*i*</sub>*ϕ̂*<sub>*j*</sub>*ϕ̂*<sub>*k*</sub>*ϕ̂*<sub>*l*</sub>
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From the superpotential, all the*F*-terms
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$|F|^2 = \\sum_i \\left|\\frac{\\partial \\tilde{W}}{\\partial \\phi_i}\\right|^2$
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and interactions of matter fermions
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$\\mathfrak{L}_Y = - \\frac{1}{2} \\frac{\\partial^2 \\tilde{W}}{\\partial \\phi_i \\partial \\phi_j} \\psi_i \\psi_j + \\mbox{h.c.} ,$
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are derived. Here*W̃* is the superpotential*W* with all superfields*ϕ̂*<sub>*i*</sub> replaced by their scalar component*ϕ*<sub>*i*</sub>.*ψ*<sub>*i*</sub> is the fermionic component of that superfield.
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Usually, the*F*- and*D*-terms and the soft-breaking terms for chiral and vector superfields fix the full scalar potential of the model. However, in some cases also non-canonical terms should be studied. These are for instance non-holomorphic soft-terms
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𝔏<sub>*S**B*, *N**H*</sub> = *T̃*<sup>*i**j**k*</sup>*ϕ*<sub>*i*</sub>*ϕ*<sub>*j*</sub>*ϕ*<sub>*k*</sub><sup>\*</sup>
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Those can be added as well and they are taken into account in the calculation of the vertices and masses and as consequence also in all loop calculations. However, they are not included in the calculation of the RGEs because of the lack of generic results in literature.
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See also
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-------- |
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\ No newline at end of file |
