Supergravity with a gravitino lightest supersymmetric particle

Journal Article · Fri Oct 01 04:00:00 EDT 2004 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.70.075019· OSTI ID:20705390

Feng, Jonathan L; Takayama, Fumihiro ^[1]; Shufang, Su ^[2]

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1. Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)
2. Department of Physics, University of Arizona, Tucson, Arizona 85721 (United States)

We investigate supergravity models in which the lightest supersymmetric particle (LSP) is a stable gravitino. We assume that the next-lightest supersymmetric particle (NLSP) freezes out with its thermal relic density before decaying to the gravitino at time t{approx}10{sup 4}-10{sup 8}s.In contrast to studies that assume a fixed gravitino relic density, the thermal relic density assumption implies upper, not lower, bounds on superpartner masses, with important implications for particle colliders. We consider slepton,sneutrino, and neutralino NLSPs, and determine what superpartner masses are viable in all of these cases, applying cosmic microwave background (CMB) and electromagnetic and hadronic big bang nucleosynthesis (BBN) constraints to the leading two- and three-body NLSP decays. Hadronic constraints have been neglected previously, but we find that they provide the most stringent constraints in much of the natural parameter space. We then discuss the collider phenomenology of supergravity with a gravitino LSP. We find that colliders may provide important insights to clarify BBN and the thermal history of the Universe below temperatures around 10 GeV and may even provide precise measurements of the gravitino's mass and couplings.

• OSTI ID: 20705390
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 7 Vol. 70; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
COSMIC RADIATION
COSMOLOGY
GEV RANGE
HADRONS
NUCLEOSYNTHESIS
PARTICLE DECAY
RADIOWAVE RADIATION
RELICT RADIATION
REST MASS
SPARTICLES
SUPERGRAVITY
THREE-BODY PROBLEM
UNIVERSE