On the Observability of Collective Flavor Oscillations in Diffuse Supernova Neutrino Background - High Energy Physics - Phenomenology

On the Observability of Collective Flavor Oscillations in Diffuse Supernova Neutrino Background - High Energy Physics - Phenomenology - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: Collective flavor oscillations are known to bring multiple splits in thesupernova SN neutrino and antineutrino spectra. These spectral splits dependnot only on the mass hierarchy of the neutrinos but also on the initialrelative flux composition. Observation of spectral splits in a future galacticsupernova signal is expected to throw light on the mass hierarchy pattern ofthe neutrinos. However, since the Diffuse Supernova Neutrino Background DSNBcomprises of a superposition of neutrino fluxes from all past supernovae, andsince different supernovae are expected to have slightly different initialfluxes, it is pertinent to check if the hierarchy dependent signature ofcollective oscillations can survive this averaging of the flux spectra. Sincethe actual distribution of SN with initial relative flux spectra of theneutrinos and antineutrinos is unknown, we assume a log-normal distribution forthem. We study the dependence of the hierarchy sensitivity to the mean andvariance of the log-normal distribution function. We find that the hierarchysensitivity depends crucially on the mean value of the relative initialluminosity. The effect of the width is to reduce the hierarchy sensitivity forall values of the mean initial relative luminosity. We find that in the verysmall mixing angle $\theta {13}$ limit considering only statistical errorseven for very moderate values of variance, there is almost no detectablehierarchy sensitivity if the mean relative luminosities of $u e$ and$\bar u e$ are greater than 1.

Autor: Sovan Chakraborty, Sandhya Choubey, Kamales Kar

Fuente: https://arxiv.org/