How heavy can the fermions in split supersymmetry be? A study on the gravitino and the extradimensional lightest supersymmetric partner

Journal Article · Sun May 15 04:00:00 EDT 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.71.103510· OSTI ID:20709251

Senatore, Leonardo ^[1]

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1. Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

In recently introduced split supersymmetry (SUSY) theories, in which the scale of SUSY breaking is very high, the requirement that the relic abundance of the lightest superpartner (LSP) provides the dark matter of the Universe leads to the prediction of fermionic superpartners around the weak scale. This is no longer obviously the case if the LSP is a hidden sector field, such as a gravitino or another hidden sector fermion, so it is interesting to study this scenario. We consider the case in which the next-lightest superpartner (NLSP) freezes out with its thermal relic abundance, and then it decays to the LSP. We use the constraints from big bang nucleosynthesis and cosmic microwave background, together with the requirement of attaining gauge coupling unification and that the LSP abundance provides the dark matter of the Universe, to infer the allowed superpartner spectrum. As very good news for detection of split SUSY at LHC, we find that if the gravitino is the LSP, then the only allowed NLSP has to be very purely photinolike. In this case, a photino from 700 GeV to 5 TeV is allowed, which is difficult to test at LHC. We also study the case where the LSP is given by a light fermion in the hidden sector which is naturally present in SUSY breaking in extra dimensions. We find that, in this case, a generic NLSP is allowed to be in the range 1-20 TeV, while a bino NLSP can be as light as tens of GeV.

• OSTI ID: 20709251
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 10 Vol. 71; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ABUNDANCE
CERN LHC
COSMIC RADIATION
COSMOLOGY
COUPLING
FERMIONS
GEV RANGE
NONLUMINOUS MATTER
NUCLEOSYNTHESIS
RADIOWAVE RADIATION
RELICT RADIATION
SPARTICLES
SUPERSYMMETRY
SYMMETRY BREAKING
TEV RANGE
UNIFIED GAUGE MODELS
UNIVERSE