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OATS-DAUT SEMINAR
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Speaker: Maxim Yu. Khlopov (Moscow Engineering Physics Inst. and Center for Cosmoparticle Physics, Moscow)

Title: Nonstandard nucleosynthesis as cosmological consequence of particle theory

Date: Monday, December 10th, 2007
Time: 12:00
Venue: Villa Bazzoni

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Abstract:
Cascades of energetic particles from decay of metastable primordial particles in early Universe interact with nuclei formed in SBBN and influence light element abundance. Negatively charged metastable particles can bind with He-4 in atom-like ion, strongly influencing the rate of SBBN nuclear reactions. It provides constraints on on the particles and models, which predict them, from observation of light element abundance. Composite dark matter hides stable heavy charged particles in neutral atom-like states. Physical examples of such stable particles are given. In the early Universe formation of composite dark matter is accompanied by formation of various fractions of exotic matter, which are severely constrained by observations. Observational consequences of various composite dark matter models (in particular, an interesting realization of warm dark matter scenario) as well as the possibilities of direct search of its charged constituents in cosmic rays and at accelerators are discussed. The necessary prediction of such models is existence of an atom like bound system of negatively charged particle Q^{-2} with He, which catalyzes nuclear transformations and, in particular, gives rise to formation of primordial heavy elements in the Universe after helium is formed in SBBN.
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contact: Paolo Molaro (OATS)