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Welcome to the ENUBET webpage Enhanced NeUtrino BEams from kaon Tagging



The fact that our “world” is composed of matter and not of anti-matter can be thought as the basis for our own existence. In spite of its importance, the profound reason of why this happened in the Universe and especially in the quantitative terms that we observe, remains one of the big open questions of modern science. The international community of physics is currently engaged in the construction of large experiments in Japan and in the US to study with high precision subtle differences between the transformations of muon neutrinos to electron neutrinos and those involving the corresponding anti-particles (anti-νμ → anti-νe). This is technically know as the search for “leptonic CP violation”. The observation of differences in these two processes would mark a breakthrough in particle physics: the dominance of matter over anti-matter that we observe today could actually come from the behavior of primordial neutrinos produced just after the Big Bang.



WP1: beamline

Goal: studying the precise layout of the kaon/pion focusing and transport system (hadron beam) capable of producing beams with momentum and angular distributions suited for a positron-tagged neutrino beam.

WP2: tagger prototype

Goal: building a positron tagger prototype with a reduced length in the longitudinal coordinate (3 m) and azimuthal coverage of about 50%. This detector should be able to demonstrate the feasibility of positron tagging under realistic conditions with the desired background and systematics suppression capabilities. Radiation hardness studies are also included in WP2.

WP3: electronics and readout mode

Goal: testing the readout performances of the front-end electronics for horn-based (< 10 ms proton extraction length) or static (1 s proton extraction length) focusing system.

WP4: photon veto and timing system

Goal: validating the timing accuracy of the tagger and the photon veto performance (e+/\pi^0 separation). The photon veto timing performance (about 10 ns) are not critical for cross section measurements. WP4 will also investigate the possibility of vertex reconstruction inside the tunnel to further suppress background and pave the way to “tagged neutrino beams”. The latter require a time resolution of about 100 ps and time synchronization studies with existing liquid Argon or water Cherenkov prototypes.

WP5: Simulation and assessment of systematics

Goal: performing a full simulation of the instrumented decay tunnel to determine the overall flux systematics that can be reached by the exploitation of the positron rate and the impact on a direct measurement of the nue CC cross section.