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arXiv · 0804.0391

Gravitational waves from deflagration bubbles in first-order phase transitions

Ariel Megevand
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Abstract

The walls of bubbles in a first-order phase transition can propagate either as detonations, with a velocity larger than the speed of sound, or deflagrations, which are subsonic. We calculate the gravitational radiation that is produced by turbulence during a phase transition which develops via deflagration bubbles. We take into account the fact that a deflagration wall is preceded by a shock front which distributes the latent heat throughout space and influences other bubbles. We show that turbulence can induce peak values of $Ω_{GW}$ as high as $\sim 10^{-9}$. We discuss the possibility of detecting at LISA gravitational waves produced in the electroweak phase transition with wall velocities $v_w\lesssim 10^{-1}$, which favor electroweak baryogenesis.

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Ariel Megevand. 2008-09-08. Gravitational waves from deflagration bubbles in first-order phase transitions. https://doi.org/10.1103/physrevd.78.084003

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