Letter of interest for a neutrino beam from Protvino to KM3NeT/ORCA

Abstract

The Protvino accelerator facility located in the Moscow region, Russia, is in a good position to offer a rich experimental research program in the field of neutrino physics. Of particular interest is the possibility to direct a neutrino beam from Protvino towards the KM3NeT/ORCA detector, which is currently under construction in the Mediterranean Sea 40 km offshore Toulon, France. This proposal is known as P2O. Thanks to its baseline of 2595 km, this experiment would yield an unparalleled sensitivity to matter effects in the Earth, allowing for the determination of the neutrino mass ordering with a high level of certainty after only a few years of running at a modest beam intensity of $$\approx ~90~\hbox {kW}$$≈90kW. With a prolonged exposure ($$\approx 1500\hbox { kW}\,\,\hbox {year}$$≈1500kWyear), a $$2\sigma $$2σ sensitivity to the leptonic CP-violating Dirac phase can be achieved. A second stage of the experiment, comprising a further intensity upgrade of the accelerator complex and a densified version of the ORCA detector (Super-ORCA), would allow for up to a $$6\sigma $$6σ sensitivity to CP violation and a $$10^\circ {-}17^\circ $$10∘-17∘ resolution on the CP phase after 10 years of running with a 450 kW beam, competitive with other planned experiments. The initial composition and energy spectrum of the neutrino beam would need to be monitored by a near detector, to be constructed several hundred meters downstream from the proton beam target. The same neutrino beam and near detector set-up would also allow for neutrino-nucleus cross section measurements to be performed. A short-baseline sterile neutrino search experiment would also be possible.

KM3NeT/ORCA: status and perspectives for neutrino oscillation and mass hierarchy measurements

“…First measurements performed with ORCA4, already indicate that it can observe the neutrino oscillations. Some detector design improvements are also under discussion, such as Super-ORCA [14] and P2O [15]. This work is supported by the National Science Centre, Poland (grant 2015/18/E/ST2/00758)…”

Neutrino Tagging, a new tool for accelerator based neutrino experiments

“…Gaussian priors are applied to these parameters. The standard deviations of these priors are identical to [32] and reported in Table 1.…”

“…Hence, a LBNE with a tagged beam and a mega-ton scale natural water neutrino detector should provide in about ten years of operation a sample of O(10 5 ) neutrinos [32] of the highest quality with very small systematic uncertainties. This option is therefore a viable solution for the next generations of LBNE's.…”

“…The possibility to perform a LBNE from the U70 accelerator complex in Protvino, Russia, to KM3NeT/ORCA, under construction offshore Toulon, France was discussed in detail in [32]. The experiment is referred to as P2O.…”

“…The study assumes that a 450 kW wide band beam can be delivered by U70 [36]. The neutrino spectra are assumed to be identical to the ones obtained in the initial P2O study [32]. Such a beam would allow to collect about 20 • 10 3 neutrinos and 5 • 10 3 anti-neutrinos per year with KM3NeT/ORCA.…”