Neutralino relic density in minimal [ital N]=1 supergravity

Journal Article · Fri Jan 15 00:00:00 EST 1993 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.47.376· OSTI ID:7119720

Drees, M ^[1]; Nojiri, M M ^[2]

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1. Theorie-Gruppe, DESY, Notkestrasse 85, D2000 Hamburg 52 (Germany)
2. Theory Group, Stanford Linear Accelerator Center, P.O. Box 4349, Stanford, California 94305 (United States)

We compute the cosmic relic (dark-matter) density of the lightest supersymmetric particle (LSP) in the framework of minimal [ital N]=1 supergravity models with radiative breaking of the electroweak gauge symmetry. To this end, we recalculate the cross sections for all possible annihilation processes for a general, mixed neutralino state with arbitrary mass. Our analysis includes effects of all Yukawa couplings of third-generation fermions, and allows for a fairly general set of soft supersymmetry- (SUSY-) breaking parameters at the Planck scale. We find that a cosmologically interesting relic density emerges naturally over wide regions of parameter space. However, the requirement that relic neutralinos do not overclose the Universe does not lead to upper bounds on SUSY-breaking parameters that are strictly valid for all combinations of parameters and of interest for existing or planned collider experiments; in particular, gluino and squark masses in excess of 5 TeV cannot strictly be excluded. On the other hand, in the generic'' case of a gauginolike neutralino whose annihilation cross sections are not accidentally'' enhanced by a nearby Higgs boson or [ital Z] pole, all sparticles should lie within the reach of the proposed [ital pp] and [ital e][sup +][ital e[minus]] supercolliders. We also find that requiring the LSP to provide all dark matter predicted by inflationary models imposes a strict lower bound of 40 GeV on the common scalar mass [ital m] at the Planck scale, while the lightest sleptons would have to be heavier than 100 GeV. Fortunately, a large relic neutralino density does not exclude the possibility that charginos, neutralinos, gluinos, and squarks are all within the reach of the CERN [ital e][sup +][ital e[minus]] collider LEP 200 and the Fermilab Tevatron.

• OSTI ID: 7119720
• Journal Information: Physical Review, D (Particles Fields); (United States), Vol. 47:2; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
Pa
SUPERGRAVITY
NONLUMINOUS MATTER
ANNIHILATION
COUPLING
CROSS SECTIONS
ELECTRON-POSITRON INTERACTIONS
FERMILAB TEVATRON
GRAND UNIFIED THEORY
HIGGS BOSONS
LEP STORAGE RINGS
PROTON-PROTON INTERACTIONS
RELICT RADIATION
SUPERSYMMETRY
SYMMETRY BREAKING
YUKAWA POTENTIAL
ACCELERATORS
BARYON-BARYON INTERACTIONS
BASIC INTERACTIONS
CYCLIC ACCELERATORS
ELECTROMAGNETIC INTERACTIONS
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
FIELD THEORIES
HADRON-HADRON INTERACTIONS
INTERACTIONS
LEPTON-LEPTON INTERACTIONS
MATHEMATICAL MODELS
MATTER
MICROWAVE RADIATION
NUCLEAR POTENTIAL
NUCLEON-NUCLEON INTERACTIONS
PARTICLE INTERACTIONS
PARTICLE MODELS
POSTULATED PARTICLES
POTENTIALS
PROTON-NUCLEON INTERACTIONS
RADIATIONS
STORAGE RINGS
SYMMETRY
SYNCHROTRONS
UNIFIED GAUGE MODELS
UNIFIED-FIELD THEORIES
662120* - General Theory of Particles & Fields- Symmetry
Conservation Laws
Currents & Their Properties- (1992-)
662210 - Specific Theories & Interaction Models
Particle Systematics- Unified Theories & Models- (1992-)
662340 - Hadron Interactions- (1992-)