Gravitational waves from walls bounded by strings in SO(10) model of pseudo-Goldstone dark matter

We explore the gravitational wave spectrum generated by string-wall structures in an SO (10) (Spin(10)) based scenario of pseudo-Goldstone boson dark matter (pGDM) particle. This dark matter candidate is a linear combination of the Standard Model (SM) singlets present in the 126 and 16 dimensional Higgs fields. The Higgs 126-plet vacuum expectation value (VEV) < 126(H)> leaves unbroken the Z(2) subgroup of Z(4), the center of SO (10). Among other things, this yields topologically stable cosmic strings with a string tension mu similar to < 126(H)>(2). The subsequent (spontaneous) breaking of Z(2) at a significantly lower scale by the 16-plet VEV < 16(H)> leads to the appearance of domain walls bounded by the strings produced earlier. We display the gravitational wave spectrum for G mu values varying between 10(-15) and 10(-9) (< 126(H)> similar to 10(11) - 10(14) GeV), and < 16(H)> similar to 0.1 - 10(2) TeV range (G denotes Newton's constant.) These predictions can be tested, as we show, by a variety of (proposed) experiments including LISA, ET, CE and others. (c) 2023 The Author(s). Published by Elsevier B.V.

Automated summary

This article explores the gravitational wave spectrum generated by string-wall structures in an SO(10) based scenario of pseudo-Goldstone boson dark matter particle. The predictions can be tested through various proposed experiments.