Primordial black holes from thermal inflation

Dimopoulos, Konstantinos and Markkanen, Tommi and Racioppi, Antonio and Vaskonen, Ville (2019) Primordial black holes from thermal inflation. Journal of Cosmology and Astroparticle Physics, 2019 (7). ISSN 1475-7516

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We present a novel mechanism for the production of primordial black holes (PBHs). The mechanism is based on a period of thermal inflation followed by fast-roll inflation due to tachyonic mass of order the Hubble scale. Large perturbations are generated at the end of the thermal inflation as the thermal inflaton potential turns from convex to concave. These perturbations can lead to copious production of PBHs when the relevant scales re-enter horizon. We show that such PBHs can naturally account for the observed dark matter in the Universe when the mass of the thermal inflaton is about 10^6 GeV and its coupling to the thermal bath preexisting the late inflation is of order unity. We consider also the possibility of forming the seeds of the supermassive black holes. In this case we find that the mass of the thermal inflaton is about 1 GeV, but its couplings have to be very small, 10^{-7}. Finally we study a concrete realisation of our mechanism through a running mass model.

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Journal Article
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Journal of Cosmology and Astroparticle Physics
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This is an author-created, un-copyedited version of an article accepted for publication/published in Journal of Cosmology and Astroparticle Physics. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at doi:10.1088/1475-7516/2019/07/046
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12 Aug 2019 10:25
Last Modified:
28 May 2023 04:49