Strongest experimental constraints on SU(5)[times]U(1) supergravity models

Journal Article · Sat Jan 01 04:00:00 EST 1994 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.49.355· OSTI ID:5433159

Lopez, J L; Nanopoulos, D V; Park, G T; Zichichi, A ^[1]

---

1. Center for Theoretical Physics, Department of Physics, Texas A M University, College Station, Texas 77843-4242 (United States) Astroparticle Physics Group, Houston Advanced Research Center (HARC), The Woodlands, Texas 77381 (United States) CERN, Theory Division, 1211 Geneva 23 (Switzerland) CERN, 1211 Geneva 23 (Switzerland)

We consider a class of well-motivated string-inspired flipped SU(5) supergravity models which include four supersymmetry-breaking scenarios: no-scale, strict no-scale, dilaton, and special dilaton, such that only three parameters are needed to describe all new phenomena ([ital m][sub [ital t]],tan[beta],[ital m][sub [ital [tilde g]]]). We show that the CERN LEP precise measurements of the electroweak parameters in the form of the [epsilon][sub 1] variable and the CLEO II allowed range for [ital B]([ital b][r arrow][ital s][gamma]) are at present the most important experimental constraints on this class of models. For [ital m][sub [ital t]][approx gt]155 (165) GeV, the [epsilon][sub 1] constraint [at 90 (95)% C.L.] requires the presence of light charginos ([ital m][sub [chi]1][sup [plus minus]][approx lt]50--100 GeV depending on [ital m][sub [ital t]]). Since all sparticle masses are proportional to [ital m][sub [ital [tilde g]]], [ital m][sub [chi]1][sup [plus minus]][approx lt]100 GeV implies [ital m][sub [chi]1][sup 0][approx lt]55 GeV, [ital m][sub [chi]2][sup 0][approx lt]100 GeV, [ital m][sub [ital [tilde g]]][approx lt]360 GeV, [ital m][sub [ital [tilde q]]][approx lt]350 (365) GeV, [ital m][sub [ital [tilde e]]][ital R][approx lt]80 (125) GeV, [ital m][sub [ital [tilde e]]][ital L][approx lt]120 (155) GeV, and [ital m][sub n][tilde u][approx lt]100 (140) GeV in the no-scale (dilaton) flipped SU(5) supergravity model. The [ital B]([ital b][r arrow][ital s][gamma]) constraint excludes a significant fraction of the otherwise allowed region in the ([ital m][sub [chi]1][sup [plus minus]],tan[beta]) plane (irrespective of the magnitude of the chargino mass), while future experimental improvements will result in decisive tests of these models.

• DOE Contract Number: FG05-91ER40633
• OSTI ID: 5433159
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 49:1; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

661310 -- Relativity & Gravitation-- (1992-)
662210* -- Specific Theories & Interaction Models
662440 -- Properties of Other Particles Including Hypothetical Particles-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BRANCHING RATIO
CONSTRAINTS
FIELD THEORIES
LIE GROUPS
Pa
Particle Systematics-- Unified Theories & Models-- (1992-)
SU GROUPS
SU-5 GROUPS
SUPERGRAVITY
SUPERSYMMETRY
SYMMETRY
SYMMETRY BREAKING
SYMMETRY GROUPS
U GROUPS
U-1 GROUPS
UNIFIED-FIELD THEORIES