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Naturalness in low-scale SUSY models and "non-linear" MSSM.

Antoniadis I, Babalic EM, Ghilencea DM - Eur Phys J C Part Fields (2014)

Bottom Line: This is done without introducing additional fields in the visible sector, unlike other models that attempt to reduce [Formula: see text].In the present case [Formula: see text] is reduced due to additional (effective) quartic Higgs couplings proportional to the ratio [Formula: see text] of the visible to the hidden sector SUSY breaking scales.By increasing the hidden sector scale [Formula: see text] one obtains a continuous transition for fine-tuning values, from this model to the usual (gravity mediated) MSSM-like models.

View Article: PubMed Central - PubMed

Affiliation: CERN Theory Division, 1211 Geneva 23, Switzerland.

ABSTRACT

In MSSM models with various boundary conditions for the soft breaking terms ([Formula: see text]) and for a Higgs mass of 126 GeV, there is a (minimal) electroweak fine-tuning [Formula: see text] to [Formula: see text] for the constrained MSSM and [Formula: see text] for non-universal gaugino masses. These values, often regarded as unacceptably large, may indicate a problem of supersymmetry (SUSY) breaking, rather than of SUSY itself. A minimal modification of these models is to lower the SUSY breaking scale in the hidden sector ([Formula: see text]) to few TeV, which we show to restore naturalness to more acceptable levels [Formula: see text] for the most conservative case of low [Formula: see text] and ultraviolet boundary conditions as in the constrained MSSM. This is done without introducing additional fields in the visible sector, unlike other models that attempt to reduce [Formula: see text]. In the present case [Formula: see text] is reduced due to additional (effective) quartic Higgs couplings proportional to the ratio [Formula: see text] of the visible to the hidden sector SUSY breaking scales. These couplings are generated by the auxiliary component of the goldstino superfield. The model is discussed in the limit its sgoldstino component is integrated out so this superfield is realized non-linearly (hence the name of the model) while the other MSSM superfields are in their linear realization. By increasing the hidden sector scale [Formula: see text] one obtains a continuous transition for fine-tuning values, from this model to the usual (gravity mediated) MSSM-like models.

No MeSH data available.


Related in: MedlinePlus

The dependence of minimal (left) and  (right) on  (GeV) for different , for fixed  with the other parameters allowed to vary. We allowed a  GeV (theoretical) error for  [42–44] about the central value of  GeV. For a fixed  the minimal values of ,  increase as we increase  from the lowest to the top curve, in this order:  TeV (the lower/red curve),  TeV (orange),  TeV (brown),  TeV (green),  TeV (dark green),  TeV (cyan),  TeV (blue),  TeV (dark blue),  TeV (black/top curve). The lowest two curves (red, orange) correspond to the minimal values of  and  in Figs. 2 and 3. For large enough  TeV, one recovers the MSSM-like values of ,  for a similar
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Fig4: The dependence of minimal (left) and (right) on (GeV) for different , for fixed with the other parameters allowed to vary. We allowed a  GeV (theoretical) error for [42–44] about the central value of  GeV. For a fixed the minimal values of , increase as we increase from the lowest to the top curve, in this order:  TeV (the lower/red curve),  TeV (orange),  TeV (brown),  TeV (green),  TeV (dark green),  TeV (cyan),  TeV (blue),  TeV (dark blue),  TeV (black/top curve). The lowest two curves (red, orange) correspond to the minimal values of and in Figs. 2 and 3. For large enough  TeV, one recovers the MSSM-like values of , for a similar

Mentions: Using the results in Eqs. (31) to (37) we evaluated and for fixed values of the SUSY breaking scale in the hidden sector for , subject to the EW constraints (for a discussion of these, see [30]). Note that imposing the Higgs mass range of  GeV (to allow for the theoretical error [42–44]) automatically respects these constraints [30]. For a rapid convergence of the perturbative expansion in of the Lagrangian we demanded that , where stands for SUSY breaking terms.11 The results are shown in Figs. 2, 3, and 4.


Naturalness in low-scale SUSY models and "non-linear" MSSM.

Antoniadis I, Babalic EM, Ghilencea DM - Eur Phys J C Part Fields (2014)

The dependence of minimal (left) and  (right) on  (GeV) for different , for fixed  with the other parameters allowed to vary. We allowed a  GeV (theoretical) error for  [42–44] about the central value of  GeV. For a fixed  the minimal values of ,  increase as we increase  from the lowest to the top curve, in this order:  TeV (the lower/red curve),  TeV (orange),  TeV (brown),  TeV (green),  TeV (dark green),  TeV (cyan),  TeV (blue),  TeV (dark blue),  TeV (black/top curve). The lowest two curves (red, orange) correspond to the minimal values of  and  in Figs. 2 and 3. For large enough  TeV, one recovers the MSSM-like values of ,  for a similar
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4383770&req=5

Fig4: The dependence of minimal (left) and (right) on (GeV) for different , for fixed with the other parameters allowed to vary. We allowed a  GeV (theoretical) error for [42–44] about the central value of  GeV. For a fixed the minimal values of , increase as we increase from the lowest to the top curve, in this order:  TeV (the lower/red curve),  TeV (orange),  TeV (brown),  TeV (green),  TeV (dark green),  TeV (cyan),  TeV (blue),  TeV (dark blue),  TeV (black/top curve). The lowest two curves (red, orange) correspond to the minimal values of and in Figs. 2 and 3. For large enough  TeV, one recovers the MSSM-like values of , for a similar
Mentions: Using the results in Eqs. (31) to (37) we evaluated and for fixed values of the SUSY breaking scale in the hidden sector for , subject to the EW constraints (for a discussion of these, see [30]). Note that imposing the Higgs mass range of  GeV (to allow for the theoretical error [42–44]) automatically respects these constraints [30]. For a rapid convergence of the perturbative expansion in of the Lagrangian we demanded that , where stands for SUSY breaking terms.11 The results are shown in Figs. 2, 3, and 4.

Bottom Line: This is done without introducing additional fields in the visible sector, unlike other models that attempt to reduce [Formula: see text].In the present case [Formula: see text] is reduced due to additional (effective) quartic Higgs couplings proportional to the ratio [Formula: see text] of the visible to the hidden sector SUSY breaking scales.By increasing the hidden sector scale [Formula: see text] one obtains a continuous transition for fine-tuning values, from this model to the usual (gravity mediated) MSSM-like models.

View Article: PubMed Central - PubMed

Affiliation: CERN Theory Division, 1211 Geneva 23, Switzerland.

ABSTRACT

In MSSM models with various boundary conditions for the soft breaking terms ([Formula: see text]) and for a Higgs mass of 126 GeV, there is a (minimal) electroweak fine-tuning [Formula: see text] to [Formula: see text] for the constrained MSSM and [Formula: see text] for non-universal gaugino masses. These values, often regarded as unacceptably large, may indicate a problem of supersymmetry (SUSY) breaking, rather than of SUSY itself. A minimal modification of these models is to lower the SUSY breaking scale in the hidden sector ([Formula: see text]) to few TeV, which we show to restore naturalness to more acceptable levels [Formula: see text] for the most conservative case of low [Formula: see text] and ultraviolet boundary conditions as in the constrained MSSM. This is done without introducing additional fields in the visible sector, unlike other models that attempt to reduce [Formula: see text]. In the present case [Formula: see text] is reduced due to additional (effective) quartic Higgs couplings proportional to the ratio [Formula: see text] of the visible to the hidden sector SUSY breaking scales. These couplings are generated by the auxiliary component of the goldstino superfield. The model is discussed in the limit its sgoldstino component is integrated out so this superfield is realized non-linearly (hence the name of the model) while the other MSSM superfields are in their linear realization. By increasing the hidden sector scale [Formula: see text] one obtains a continuous transition for fine-tuning values, from this model to the usual (gravity mediated) MSSM-like models.

No MeSH data available.


Related in: MedlinePlus