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Choi JH, Jang HI, Jang JS, Jeon SH, Joo KK, Ju K, Jung DE, Kim JG, Kim JH, Kim JY, Kim SB, Kim SY, Kim W, Kwon E, Lee DH, Lee HG, Lim IT, Moon DH, Pac MY, Seo H, Seo JW, Shin CD, Yang BS, Yoo J, Yoon SG, Yeo IS, Yu I. Search for Sub-eV Sterile Neutrinos at RENO. Phys Rev Lett 2020; 125:191801. [PMID: 33216576 DOI: 10.1103/physrevlett.125.191801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 10/08/2020] [Accepted: 10/09/2020] [Indexed: 06/11/2023]
Abstract
We report a search result for a light sterile neutrino oscillation with roughly 2200 live days of data in the RENO experiment. The search is performed by electron antineutrino (ν[over ¯]_{e}) disappearance taking place between six 2.8 GW_{th} reactors and two identical detectors located at 294 m (near) and 1383 m (far) from the center of the reactor array. A spectral comparison between near and far detectors can explore reactor ν[over ¯]_{e} oscillations to a light sterile neutrino. An observed spectral difference is found to be consistent with that of the three-flavor oscillation model. This yields limits on sin^{2}2θ_{14} in the 10^{-4}≲|Δm_{41}^{2}|≲0.5 eV^{2} region, free from reactor ν[over ¯]_{e} flux and spectrum uncertainties. The RENO result provides the most stringent limits on sterile neutrino mixing at |Δm_{41}^{2}|≲0.002 eV^{2} using the ν[over ¯]_{e} disappearance channel.
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Affiliation(s)
- J H Choi
- Institute for High Energy Physics, Dongshin University, Naju 58245, Korea
| | - H I Jang
- Department of Fire Safety, Seoyeong University, Gwangju 61268, Korea
| | - J S Jang
- GIST College, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - S H Jeon
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - K K Joo
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - K Ju
- Department of Physics, KAIST, Daejeon 34141, Korea
| | - D E Jung
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - J G Kim
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - J H Kim
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - J Y Kim
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - S B Kim
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - S Y Kim
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - W Kim
- Department of Physics, Kyungpook National University, Daegu 41566, Korea
| | - E Kwon
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - D H Lee
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - H G Lee
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - I T Lim
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - D H Moon
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - M Y Pac
- Institute for High Energy Physics, Dongshin University, Naju 58245, Korea
| | - H Seo
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
| | - J W Seo
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - C D Shin
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - B S Yang
- Institute for Basic Science, Daejeon 34047, Korea
| | - J Yoo
- Department of Physics, KAIST, Daejeon 34141, Korea
- Institute for Basic Science, Daejeon 34047, Korea
| | - S G Yoon
- Department of Physics, KAIST, Daejeon 34141, Korea
| | - I S Yeo
- Institute for Universe and Elementary Particles, Chonnam National University, Gwangju 61186, Korea
| | - I Yu
- Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
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Yoon SG, Kim SW, Yoon DH, Hirano M, Hosono H. Single crystal growth of nanoporous C12A7:e- by controlling melt state. J Nanosci Nanotechnol 2009; 9:7345-7349. [PMID: 19908785 DOI: 10.1166/jnn.2009.1747] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
It has been known that electron doped 12CaO x 7Al2O3 (C12A7:e-, electride) single crystals, which are composed of a closed-packed periodic quantum dot structure, may be prepared by strong reduction of the precursor C12A7:O2-, but direct single crystal growth of the C12A7:e- from the melt state has never been achieved to date. We report the melt state of polycrystalline electride in pure dry Ar atmosphere at temperatures of 1290 approximately 1500 degrees C, which leads to the direct single crystal growth of the C12A7:e- from the melt. The electride single crystals with a diameter of 7 mm and a length of 43 mm have been grown by a floating zone method, where a polycrystalline electride feed and an electride single crystal seed rod were employed. The electron concentration in the crystal increased up to approximately 1.0 x 10(20) cm(-3) as the growth proceeded. The present findings suggest that electron-entrapped local structure may exist in the melt and the electrons may act as a template for the formation of C12A7 electride in the solidification process of the C12A7 lattice.
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Affiliation(s)
- S G Yoon
- Frontier Collaborative Research Center, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
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Kang SM, Yoon SG, Kim SW, Yoon DH. Luminescence tuning of amorphous Si quantum dots prepared by plasma-enhanced chemical vapor deposition. J Nanosci Nanotechnol 2008; 8:2540-2543. [PMID: 18572680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Amorphous Si (a-Si) quantum dots (QDs) embedded in a silicon nitride film were prepared by a plasma-enhanced chemical vapor deposition (PECVD) technique using gaseous mixtures of silane, hydrogen and nitrogen. We observed that the Si QDs had an amorphous structure from the Raman spectroscopy measurement. The Fourier transform infrared (FTIR) spectra showed that the relative transmittance of the SiH bands decreased, but that of the NH bands increased, with increasing nitrogen flow rate. During the deposition of SiNx, the number of dangling bonds of silicon acting as nucleation sites increased. As the hydrogen flow rate increased the growth rate decreased, due to the reduction in the hydrogen partial pressure. The hydrogen and nitrogen gas flow rates were found to be important parameters for determining the size of the a-Si QDs. In addition, we observed that the PL peak shifted toward a higher energy with increasing hydrogen and nitrogen gas flow rates, which was attributed to the increase in the quantum confinement effect in the a-Si QDs.
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Affiliation(s)
- S M Kang
- Department of Advanced Materials Engineering, Sungkyunkwan University, Suwon 440-746, Korea
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Abstract
Factor V deficiency is a relatively uncommon disorder, inherited as an autosomal recessive trait that manifests clinically only in individuals who inherit the defective gene from both parents. The hemorrhage of nasal and oral cavity and ecchymosis are common but intracranial hemorrhage is very rare. We experienced a 53 year old male patient with intracranial hemorrhage due to factor V deficiency. The laboratory tests showed prolongation of APTT and PT, normal bleeding time and normal thrombin time. The levels of the coagulation profiles on the patient revealed a significant decrease factor V, below 1% of normal range (60-140%). Other coagulation factors were normal. He was treated with fresh frozen plasma and completely recovered 3 weeks after treatment.
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Affiliation(s)
- S G Yoon
- Institute for Clinical molecular Biology Research, College of Medicine, Soonchunhyang University, Seoul, Korea
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Yoon SG, Kim HG. Characterization and electrical properties of chemical vapor deposited ferroelectric lead titanate films on titanium. IEEE Trans Ultrason Ferroelectr Freq Control 1990; 37:333-338. [PMID: 18285049 DOI: 10.1109/58.105238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Lead titanate thin films were deposited on titanium substrates by a chemical vapor deposition (CVD) process involving the application of vapor mixtures of Pb, ethyl titanate (Ti(C(2)H(5)O) (4)), and oxygen. Auger electron spectroscopy (AES) analyses were performed to determine the chemical composition of lead titanate films. AES analysis revealed that TiO(2) and TiO interlayers formed between the PbTiO(3) and titanium substrate. AES also showed that stoichiometry was obtained in the lead titanate film deposited at 750 degrees C, Ti(C(2)H(2)O)(4) with 0.152, an O(2) partial pressure of 0.06 atm, and a gas flow rate of 800 sccm. The lead titanate with a stoichiometric composition has a DC conductivity of 3.2x10(-12) Omega(-1)-cm(-1) at room temperature. The nonsaturating loops observed in the present investigation may be caused by TiO(2) and TiO layers between the conductive substrate and the PbTiO(3) ferroelectric film. The ferroelectric properties of the stoichiometric PbTiO(3) film included a remanent polarization of 14.1 muC/cm(3) and a coercive field of 20.16 kV/cm.
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Affiliation(s)
- S G Yoon
- Dept. of Mater. Sci. and Eng., Korea Adv. Inst. of Sci. and Technol., Seoul
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