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تسجيل مستخدم جديدStealth dark matter and gravitational waves
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David Schaich
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I present first results from ongoing lattice investigations into the finite-temperature dynamics of stealth dark matter, which adds to the standard model a new SU(4) gauge sector with four moderately heavy fundamental fermions. This work by the Lattice Strong Dynamics Collaboration builds on past studies of direct detection and collider searches for stealth dark matter, by analyzing the early-universe SU(4) confinement transition, which produces a stochastic background of gravitational waves if it is first order. In addition to delineating the parameter space in which a first-order transition is observed, I discuss the quantities we are analyzing in order to predict the resulting gravitational-wave spectrum.
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We use non-perturbative lattice calculations to investigate the finite-temperature confinement transition of stealth dark matter, focusing on the regime in which this early-universe transition is first order and would generate a stochastic background
of gravitational waves. Stealth dark matter extends the standard model with a new strongly coupled SU(4) gauge sector with four massive fermions in the fundamental representation, producing a stable spin-0 dark baryon as a viable composite dark matter candidate. Future searches for stochastic gravitational waves will provide a new way to discover or constrain stealth dark matter, in addition to previously investigated direct-detection and collider experiments. As a first step to enabling this phenomenology, we determine how heavy the dark fermions need to be in order to produce a first-order stealth dark matter confinement transition.
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