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arXiv · 0805.3300

Collective neutrino oscillations in non-spherical geometry

Basudeb Dasgupta·Amol Dighe·Alessandro Mirizzi·Georg G. Raffelt
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Abstract

The rich phenomenology of collective neutrino oscillations has been studied only in one-dimensional or spherically symmetric systems. Motivated by the non-spherical example of coalescing neutron stars, presumably the central engines of short gamma-ray bursts, we use the Liouville equation to formulate the problem for general source geometries. Assuming the neutrino ensemble displays self-maintained coherence, the problem once more becomes effectively one-dimensional along the streamlines of the overall neutrino flux. This approach for the first time provides a formal definition of the ``single-angle approximation'' frequently used for supernova neutrinos and allows for a natural generalization to non-spherical geometries. We study the explicit example of a disk-shaped source as a proxy for coalescing neutron stars.

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Basudeb Dasgupta, Amol Dighe, Alessandro Mirizzi, Georg G. Raffelt. 2008-05-21. Collective neutrino oscillations in non-spherical geometry. https://doi.org/10.1103/physrevd.78.033014

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