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Coupled DM heating in SCDEW cosmologies

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 نشر من قبل Roberto Mainini
 تاريخ النشر 2017
  مجال البحث فيزياء
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Strongly Coupled Dark Energy plus Warm dark matter (SCDEW) cosmologies admit the stationary presence of $sim 1, %$ of coupled-DM and DE, since inflationary reheating. Coupled-DM fluctuations therefore grow up to non-linearity even in the early radiative expansion. Such early non-linear stages are modelized here through the evolution of a top-hat density enhancement, reaching an early virial balance when the coupled-DM density contrast is just 25-26 and DM density enhancement is $ sim 10, %$ of total density. During the time needed to settle in virial equilibium, the virial balance conditions however continue to modify, so that virialized lumps undergo a complete evaporation. Here we outline that DM particles processed by overdentities preserve a fraction of their virial momentum. Although fully non-relativistic, the resulting velocities (moderately) affect the fluctuation dynamics over greater scales, entering the horizon later on.

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