Towards the detection of cosmological relic neutrinos with neutrino capture on beta decaying nuclei

par Dr Marcello Messina (Albert Einstein Center for Fundamental Physics Laboratory for High Energy Physics' - University of Bern)

vendredi 15 avr. 2011, 14:00 → 14:35 Europe/Paris

Auditorium M. Vivargent (LAPP)

In the talk I will illustrate a novel idea for the detection Cosmological Relic Neutrinos CRN) and more in general, for the detection of neutrinos of vanishing energy. This idea is described in detail in the paper [1]. The method is based on the fact that neutrino interactions on beta-instable nuclei have the key feature of requiring no energy threshold for the neutrino interaction. Furthermore, as proved in the reference [1], a very interesting feature of sigma-nu is shown for neutrino interacting with beta-instable nuclei: even if the kinetic neutrino energy vanishes sigma-nu keeps a constant value depending on the considered target nucleus. This allows in principle the detection of neutrinos of vanishing energy. To achieve the high detection sensitivity one needs for CRNs discovery new developments are necessary in the field of detectors technology. In the talk I discuss the possibility of building a bolometer with an absorber mass as large as ~1 g and, with an energy resolution of a fraction of eV. To accomplish this goal it is needed to investigate several read-out set-ups and understand which could fit our experimental requests. Morover, I also discuss the magnetic flux based read-out of bolometers arranged in a geometrically metastable geometry. This looks to be a promising detector scheme in view of realizing bolometers with large mass absorbers (~1 g). The detector development I show is a mandatory step in view of the design of future detectors for CRN on a realistically large scale. [1] A. Cocco, G. Mangano and M. Messina, “Probing Low Energy Neutrino Backgrounds with Neutrino Capture on Beta Decaying Nuclei,” Journal of Cosmological and Astroparticle Physics 0706 15 (2007).

Slides annecy_2011.pdf