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What if Supersymmetry Breaking Unifies beyond the GUT Scale?

We study models in which soft supersymmetry-breaking parameters of the MSSM become universal at some unification scale, $M_{in}$, above the GUT scale, $\mgut$. We assume that the scalar masses and gaugino masses have common values, $m_0$ and $m_{1/2}$ respectively, at $M_{in}$. We use the renormaliz...

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Detalles Bibliográficos
Autores principales: Ellis, John, Mustafayev, Azar, Olive, Keith A.
Formato: info:eu-repo/semantics/article
Lenguaje:eng
Publicado: Eur. Phys. J. C 2010
Materias:
Acceso en línea:https://dx.doi.org/10.1140/epjc/s10052-010-1373-8
http://cds.cern.ch/record/1254335
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author Ellis, John
Mustafayev, Azar
Olive, Keith A.
author_facet Ellis, John
Mustafayev, Azar
Olive, Keith A.
author_sort Ellis, John
collection CERN
description We study models in which soft supersymmetry-breaking parameters of the MSSM become universal at some unification scale, $M_{in}$, above the GUT scale, $\mgut$. We assume that the scalar masses and gaugino masses have common values, $m_0$ and $m_{1/2}$ respectively, at $M_{in}$. We use the renormalization-group equations of the minimal supersymmetric SU(5) GUT to evaluate their evolutions down to $\mgut$, studying their dependences on the unknown parameters of the SU(5) superpotential. After displaying some generic examples of the evolutions of the soft supersymmetry-breaking parameters, we discuss the effects on physical sparticle masses in some specific examples. We note, for example, that near-degeneracy between the lightest neutralino and the lighter stau is progressively disfavoured as $M_{in}$ increases. This has the consequence, as we show in $(m_{1/2}, m_0)$ planes for several different values of $\tan \beta$, that the stau coannihilation region shrinks as $M_{in}$ increases, and we delineate the regions of the $(M_{in}, \tan \beta)$ plane where it is absent altogether. Moreover, as $M_{in}$ increases, the focus-point region recedes to larger values of $m_0$ for any fixed $\tan \beta$ and $m_{1/2}$. We conclude that the regions of the $(m_{1/2}, m_0)$ plane that are commonly favoured in phenomenological analyses tend to disappear at large $M_{in}$.
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spelling cern-12543352023-03-14T20:31:31Z doi:10.1140/epjc/s10052-010-1373-8 http://cds.cern.ch/record/1254335 eng Ellis, John Mustafayev, Azar Olive, Keith A. What if Supersymmetry Breaking Unifies beyond the GUT Scale? Particle Physics - Phenomenology We study models in which soft supersymmetry-breaking parameters of the MSSM become universal at some unification scale, $M_{in}$, above the GUT scale, $\mgut$. We assume that the scalar masses and gaugino masses have common values, $m_0$ and $m_{1/2}$ respectively, at $M_{in}$. We use the renormalization-group equations of the minimal supersymmetric SU(5) GUT to evaluate their evolutions down to $\mgut$, studying their dependences on the unknown parameters of the SU(5) superpotential. After displaying some generic examples of the evolutions of the soft supersymmetry-breaking parameters, we discuss the effects on physical sparticle masses in some specific examples. We note, for example, that near-degeneracy between the lightest neutralino and the lighter stau is progressively disfavoured as $M_{in}$ increases. This has the consequence, as we show in $(m_{1/2}, m_0)$ planes for several different values of $\tan \beta$, that the stau coannihilation region shrinks as $M_{in}$ increases, and we delineate the regions of the $(M_{in}, \tan \beta)$ plane where it is absent altogether. Moreover, as $M_{in}$ increases, the focus-point region recedes to larger values of $m_0$ for any fixed $\tan \beta$ and $m_{1/2}$. We conclude that the regions of the $(m_{1/2}, m_0)$ plane that are commonly favoured in phenomenological analyses tend to disappear at large $M_{in}$. We study models in which soft supersymmetry-breaking parameters of the MSSM become universal at some unification scale, $M_{in}$, above the GUT scale, $\mgut$. We assume that the scalar masses and gaugino masses have common values, $m_0$ and $m_{1/2}$ respectively, at $M_{in}$. We use the renormalization-group equations of the minimal supersymmetric SU(5) GUT to evaluate their evolutions down to $\mgut$, studying their dependences on the unknown parameters of the SU(5) superpotential. After displaying some generic examples of the evolutions of the soft supersymmetry-breaking parameters, we discuss the effects on physical sparticle masses in some specific examples. We note, for example, that near-degeneracy between the lightest neutralino and the lighter stau is progressively disfavoured as $M_{in}$ increases. This has the consequence, as we show in $(m_{1/2}, m_0)$ planes for several different values of $\tan \beta$, that the stau coannihilation region shrinks as $M_{in}$ increases, and we delineate the regions of the $(M_{in}, \tan \beta)$ plane where it is absent altogether. Moreover, as $M_{in}$ increases, the focus-point region recedes to larger values of $m_0$ for any fixed $\tan \beta$ and $m_{1/2}$. We conclude that the regions of the $(m_{1/2}, m_0)$ plane that are commonly favoured in phenomenological analyses tend to disappear at large $M_{in}$. info:eu-repo/grantAgreement/EC/FP7/237920 info:eu-repo/semantics/openAccess Education Level info:eu-repo/semantics/article http://cds.cern.ch/record/1254335 Eur. Phys. J. C Eur. Phys. J. C, (2010) pp. 201-217 2010-03-22
spellingShingle Particle Physics - Phenomenology
Ellis, John
Mustafayev, Azar
Olive, Keith A.
What if Supersymmetry Breaking Unifies beyond the GUT Scale?
title What if Supersymmetry Breaking Unifies beyond the GUT Scale?
title_full What if Supersymmetry Breaking Unifies beyond the GUT Scale?
title_fullStr What if Supersymmetry Breaking Unifies beyond the GUT Scale?
title_full_unstemmed What if Supersymmetry Breaking Unifies beyond the GUT Scale?
title_short What if Supersymmetry Breaking Unifies beyond the GUT Scale?
title_sort what if supersymmetry breaking unifies beyond the gut scale?
topic Particle Physics - Phenomenology
url https://dx.doi.org/10.1140/epjc/s10052-010-1373-8
http://cds.cern.ch/record/1254335
http://cds.cern.ch/record/1254335
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