Imprints of the Standard Model in the Sky: Gravitational Waves from the decay of the Higgs after inflation

Understand

The existence of the Standard Model (SM) Higgs implies that a gravitational wave (GW) background is generated by the decay products of the Higgs, soon after the end of inflation.

• Theoretically, all Yukawa and $SU(2)_L$ gauge couplings of the SM are imprinted as features in the GW spectrum.
• In practice, the signal from the most strongly coupled species dominates, rendering inaccesible the information on the other species.
• If detected, this background could be used for measuring properties of high-energy particle physics, including beyond the SM.