Neutrinos are one of the least understood fundamental particles. Studying neutrinos provide insight into undiscovered principles of nature. The Coherent Elastic Neutrino-Nucleus Scattering process, or CENNS, has been observed in 2017. The coherence conditions requires a sufficiently small momentum transfer to the target nucleus so that the waves of the off-scattered nucleons in the nucleus are all in phase and add up coherently. The CENNS is one of the most important step towards approaching the vast unexplored low energy neutrino physics --- a vital process leading to supernova explosion, r-process nucleosynthesis of the elements and fundamental tests of the Standard Model, that includes measurements of weak mixing angles and the search for exotic new physics such as a neutrino magnetic moment, sterile neutrinos, background of dark matter searches, and non-standard neutrino interactions.
• First Probe of Sub-GeV Dark Matter beyond the Cosmological Expectation with the COHERENT CsI Detector at the SNS (PRL 130 051803) 2023-02-03
• Measurement of scintillation response of CsI[Na] to low-energy nuclear recoils by COHERENT (JINST 17 P10034) 2022-10-21
• COHERENT constraint on leptophobic dark matter using CsI data (PRD 106 052004) 2022-09-14
• Measurement of the Coherent Elastic Neutrino-Nucleus Scattering Cross Section on CsI (PRL 129 081801) 2022-08-17
• Simulating the neutrino flux from the Spallation Neutron Source for the COHERENT experiment (PRD 106 032003) 2022-08-02
• Monitoring the SNS basement neutron background with the MARS detector (JINST 17 P03021) 2022-03-22
• First Measurement of Coherent Elastic Neutrino-Nucleus Scattering on Argon (PRL 126 012002) 2021-01-07
• A D2O detector for flux normalization of a pion decay-at-rest neutrino source (JINST 16 P08048) 2021-08-16
• Development of a 83mKr for the calibration of the CENNS-10 Liquid Argon Detector (JINST 16 P04002) 2021-04-01
• Sensitivity of the COHERENT experiment to accelerator-produced dark matter (PRD 102, 052007) 2020-09-29
• First constraint on coherent elastic neutrino-nucleus scattering in argon (PRD 100, 115020) 2019-12-09 [Editor's suggestion]
• Observation of coherent elastic neutrino-nucleus scattering (Science 357, 6356) 2017-08-03
In the Standard Model, neutrinos are assumed to have zero mass. However, experimental observations during the last two decades showed that this assumption is incorrect. Neutrino flavor oscillation is a quantum mechanical flavor mixing phenomena where a neutrino created with a lepton flavor can be transformed into a different flavor. Neutrino oscillation through flavor mixing implies that neutrinos have non-zero mass. The detailed study of the neutrino flavor mixing matrix may also provide solutions to understand the matter dominant Universe.
• Measurement of cosmogenic 9Li and 8He production rates at RENO (PRD 106, 012005) 2022-07-20
• Search for sterile neutrino oscillation using RENO and NEOS data (PRD 105, L111101) 2022-06-08
• Measurement of Reactor Antineutrino Flux and Spectrum at RENO (PRD 104, L111301) 2021-12-09
• Search for Sub-eV Sterile Neutrino at RENO (PRL 125, 191801) 2020-11-06
• Observation of reactor antineutrino disappearance using delayed neutron capture on hydrogen at RENO (JHEP 04 029) 2020-04-06
• Fuel-composition dependent reactor neutrinos from RENO experiment (PRL 122, 232501) 2019-06-12
• Neutrino oscillation study from RENO experiment (PRL 121, 201801) 2018-11-15
It has now been proven that the major matter component of the Universe is dark matter. The Standard Model does not accommodate a suitable dark matter candidate. Therefore the existence of dark matter is a crucial phenomenological evidence for physics Beyond the Standard Model. The pressing goal of current and future dark matter experiments is to answer the question of whether dark matter interacts with normal matter other than gravity; i.e. if dark matter is detectable. We are developing experiment to directly detect those dark matters.
One of the strong candidate of the dark matter is the hypothetical particle called axions. The axion has been postulated to solve the strong-CP problem in quantum chromodynamics. The strong-CP problem is manifested by the null observation of the neutron’s electric dipole moment. The Peccei-Quinn U(1) symmetry breaking mechanism was suggested as a solution to the problem. The mechanism leaves a pseudo-Goldstone boson field, interpreted as the axion. Moreover, the non-thermal axion production mechanism in the early Universe suggests the axion as a cold dark matter candidate. Especially a light axion is an ideal dark matter candidate which would have been produced during the Big Bang. The ultimate goal of the axion experiments at our lab is to discover the axion dark matters. The discovery of the axion will resolve the strong-CP problem, and the discovery of dark matter will revolutionize our understanding of the Universe.
• Axion Haloscope Using an 18 T High Temperature Superconducting Magnet (PRD 106 092007) 2022-11-29
• Searching for invisible axion dark matter with an 18 T magnet haloscope (PRL 128, 241805) 2022-06-17
• Design, construction, and operation of an 18 T 70 mm magnet for an axion haloscope experiment (RSI 91, 023314) 2020-02-06
• Magnetoresistance in copper at high frequency and high magnetic fields (JINST 12 P10023) 2017-10-31