Cosmic Strings from Supersymmetric Flat Directions - High Energy Physics - PhenomenologyReport as inadecuate

Cosmic Strings from Supersymmetric Flat Directions - High Energy Physics - Phenomenology - Download this document for free, or read online. Document in PDF available to download.

Abstract: Flat directions are a generic feature of the scalar potential insupersymmetric gauge field theories. They can arise, for example, from D-termsassociated with an extra abelian gauge symmetry. Even when supersymmetry isbroken softly, there often remain directions in the scalar field space alongwhich the potential is almost flat. Upon breaking a gauge symmetry along one ofthese almost flat directions, cosmic strings may form. Relative to the standardcosmic string picture based on the abelian Higgs model, these flat-directioncosmic strings have the extreme Type-I properties of a thin gauge coresurrounded by a much wider scalar field profile. We perform a comprehensivestudy of the microscopic, macroscopic, and observational characteristics ofthis class of strings. We find many differences from the standard stringscenario, including stable higher winding mode strings, the dynamical formationof higher mode strings from lower ones, and a resultant multi-tension scalingstring network in the early universe. These strings are only moderatelyconstrained by current observations, and their gravitational wave signaturesmay be detectable at future gravity wave detectors. Furthermore, there is theinteresting but speculative prospect that the decays of cosmic string loops inthe early universe could be a source of ultra-high energy cosmic rays ornon-thermal dark matter. We also compare the observational signatures offlat-direction cosmic strings with those of ordinary cosmic strings as well asp,q cosmic strings motivated by superstring theory.

Author: Yanou Cui, Stephen P. Martin, David E. Morrissey, James D. Wells


Related documents