English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We study the possible decay of a coherently oscillating scalar field,interpreted as dark matter, into light fermions. Specifically, we consider ascalar field with sub-eV mass decaying into a Fermi sea of neutrinos. Werecognize the similarity between our scenario and inflationary preheating wherea coherently oscillating scalar field decays into standard model particles.Like the case of fermionic preheating, we find that Pauli blocking controls thedark matter decay into the neutrino sea. The radius of the Fermi sphere dependson the expansion of the universe leading to a time varying equation of state ofdark matter. This makes the scenario very rich and we show that the decay ratemight be different at different cosmological epochs. We categorize this in twointeresting regimes and then study the cosmological perturbations to find theimpact on structure formation. We find that the decay may help alleviating someof the standard problems related to cold dark matter.

Dark Matter Decaying into a Fermi Sea of Neutrinos