View source for Reactor Experiment for Neutrino Oscillation

{{short description|Neutrino oscillation experiment in South Korea}}
{{redirect|RENO|other uses|Reno (disambiguation)}}
The '''Reactor Experiment for Neutrino Oscillation''' ('''RENO''') is a short baseline reactor [[neutrino oscillation]] experiment in [[South Korea]]. The experiment was designed to either measure or set a limit on the [[Pontecorvo–Maki–Nakagawa–Sakata matrix|neutrino mixing matrix]] parameter ''θ''<sub>13</sub>, a parameter responsible for oscillations of [[electron neutrino]]s into other neutrino flavours. RENO has two identical detectors, placed at distances of 294 m and 1383 m, that observe electron antineutrinos produced by six reactors at the [[Hanbit Nuclear Power Plant]] (the old name: the Yeonggwang Nuclear Power Plant) in Korea.

Each detector consists of {{val|16.5|ul=t}} of [[gadolinium]]-doped liquid scintillator ([[Linear alkylbenzene|LAB]]), surrounded by an additional 450 tons of buffer, veto, and shielding liquids.<ref name=neutrino2016>{{Cite conference |url=http://neutrino2016.iopconfs.org/IOP/media/uploaded/EVIOP/event_948/09.45___2_.ppt |title=Results from RENO and prospects with RENO-50 |first=Kyung Kwang |last=Joo |date=5 July 2016 |location=London |conference=XXVII International Conference on Neutrino Physics and Astrophysics |conference-url=http://neutrino2016.iopconfs.org/programme}}  Video available at {{youtube|id=Z0xyRySZi0Q#t=45m17s|Neutrino Conference 2016 - Tuesday (part 1)}}.</ref>{{Rp|6}}

On 3 April 2012, with some corrections on 8 April, the RENO collaboration announced  a [[Statistical significance#In terms of σ (sigma)|4.9σ]]{{Broken anchor|date=2024-05-29|bot=User:Cewbot/log/20201008/configuration|target_link=Statistical significance#In terms of σ (sigma)|reason= The anchor (In terms of σ (sigma)) [[Special:Diff/583344693|has been deleted]].}} observation of ''θ''<sub>13</sub>&nbsp;≠&nbsp;0, with
:<math>\sin^2 2\theta_{13} = 0.113 \pm 0.013({\rm stat.}) \pm 0.019({\rm syst.})</math><ref>{{cite journal |author=RENO Collaboration |journal=Physical Review Letters |volume=108 |issue=18 |page=191802 |doi=10.1103/PhysRevLett.108.191802 |pmid=23003027 |arxiv=1204.0626 |title=Observation of electron-antineutrino disappearance at RENO |date=2012-04-03 |bibcode=2012PhRvL.108s1802A |s2cid=33056442 }}</ref><ref>{{cite web |author=RENO Collaboration |url=http://www.interactions.org/cms/?pid=1031612 |title=Announcement of the First Results from RENO: Observation of the Weakest Neutrino Transformation|publisher=Interactions NewsWire|date=2012-04-04}}</ref>

This measurement confirmed a similar result announced by the [[Daya Bay Reactor Neutrino Experiment|Daya Bay Experiment]] three weeks before and is consistent with earlier, but less significant results by [[T2K]], [[MINOS]] and [[Double Chooz]].

RENO released updated results<ref>{{cite arXiv|author=Seon-Hee Seo (for the RENO Collaboration)|title=New Results from RENO|eprint=1312.4111|class=physics.ins-det|year=2013}}</ref> in December 2013, confirming ''θ''<sub>13</sub> ≠ 0 with a significance of 6.3σ:

:<math> \sin^2 2 \theta_{13} = 0.100 \pm 0.010({\rm stat.}) \pm 0.015({\rm syst.})</math>

In 2014, RENO announced the observation of an unexpectedly large number of neutrinos with an energy of {{val|5|1|ul=MeV}}.<ref name=neutrino2014>{{Cite conference |url=https://indico.fnal.gov/getFile.py/access?contribId=255&sessionId=15&resId=0&materialId=slides&confId=8022 |title=New Results from RENO |first=Seon-Hee |last=Seo |date=3 June 2014 |location=Boston |conference=XXVI International Conference on Neutrino Physics and Astrophysics |conference-url=http://neutrino2014.bu.edu/program/}}</ref>{{Rp|14–15}}  This has since been confirmed by the Daya Bay and Double Chooz experiments,<ref name=neutrino2016/>{{Rp|14–17}} and the cause remains an outstanding puzzle.

Expansion plans, referred to as RENO-50, will add a third medium-baseline detector at a distance of 47&nbsp;km.  This distance is better for observing [[neutrino oscillations]], but requires a much larger detector due to the smaller neutrino flux.  The location, near [[Dongshin University]], has a 450&nbsp;m high mountain (Mt. Guemseong), which will provide 900&nbsp;[[Meter water equivalent|m.w.e.]] shielding for the detector.  If funded, this will contain {{val|18000|u=t}} of scintillator,<ref name=neutrino2016/>{{Rp|31}} surrounded by {{val|15000}} [[photomultiplier]] tubes.

==References==
{{Reflist}}

{{neutrino detectors}}

[[Category:Neutrino experiments]]
[[Category:Reactor neutrino experiments]]


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