RENO: An Experiment for Neutrino Oscillation Parameter theta_13 Using Reactor Neutrinos at Yonggwang

TL;DR

The RENO study proposes a two-detector reactor neutrino experiment at Yonggwang to measure the mixing angle $\theta_{13}$ by observing $\bar{\nu}_e$ disappearance. It combines a LAB-based, Gd-loaded liquid scintillator target with a gamma catcher, buffer, and veto in two identical detectors to cancel reactor-related systematics and achieve a projected sensitivity of $\sin^2(2\theta_{13})\approx 0.02$ after three years. The design leverages detailed Monte Carlo simulations (GEANT4-based) for optimization, backgrounds, and reconstruction, alongside a comprehensive calibration program (radioactive and light sources). The work situates RENO within the broader neutrino program, highlighting its role in enabling CP-violation measurements and guiding future accelerator-based explorations, while also detailing potential extended physics such as sterile neutrinos and geo-neutrinos. Overall, RENO aims for a precise, relatively low-cost determination or limit on $\theta_{13}$ with strong implications for the neutrino oscillation landscape and CP studies.

Abstract

The RENO experiment is a short baseline neutrino experiment in Korea aiming to measure the neutrino mixing angle theta_13 or set limit to sin^2(2 theta_13) less than 0.02. This document describes physics goals, experimental site, detector design, scintillator, electronics, calibration, simulation, and physics reach.

Figures (91)

• Figure 1: Yonggwang nuclear power plant. The power plant is located about 250 km south of Seoul. Three other nuclear power plant sites in Korea are also shown.
• Figure 2: The layout of the Yonggwang experiment site. Red dots and yellow dots represent reactors and detectors, respectively. Six reactors are roughly equally spaced in a 1280 m span. The near and far detectors are 290 m and 1380 m away from the reactor array, respectively. The image taken from Google Earth$^{\rm TM}$ and copyrighted therein.
• Figure 3: Overall side view of RENO experiment. The near detector is under a 70 m hill located within the perimeter of the power plant whereas the far detector is located under a 200 m mountain near the power plant.
• Figure 4: Plan of the access tunnel (top) and 3D schematic for experimental hall (bottom). The tunnels are constructed using NATM.
• Figure 5: Locations of the electrical resistivity survey (red) and seismic refraction test (blue) performed in near (left) and far (right) detector sites.