Cosmological Signature of Light Sgoldstino: Gravitational Waves from Electroweak Phase Transition

The contribution of light sgoldstinos with masses about 100 GeV to the effective potential at a finite temperature is considered in the model with spontaneously broken supersymmetry at the scale of 10-100 TeV. The possibility of the first-order electroweak phase transition due to this contribution is studied. The region in the model parameter space, in which such a transition can occur, is numerically searched. Using the PhaseTracer and FindBounce packages, several benchmark points with electroweak phase transitions at temperatures of 60-140 GeV were found. The power spectra of gravitational waves produced during the electroweak phase transition is also estimated. The predicted signals can be observed by the LISA, BBO, and DECIGO experiments.