ABSTRACT We present a search, using KamLAND, a kiloton-scale anti-neutrino detector, for low-energy anti-neutrino events that were coincident with the gravitational-wave (GW) events GW150914 and ...GW151226, and the candidate event LVT151012. We find no inverse beta-decay neutrino events within 500 s of either GW signal. This non-detection is used to constrain the electron anti-neutrino fluence and the total integrated luminosity of the astrophysical sources.
The amount of 8‐hydroxydeoxyguanosine (8‐OH‐dG) excreted in urine can be used not only as an indicator of DNA repair capacity, but also as a potential marker of oxidative DNA damage. To clarify the ...oxidation‐related factors, in consideration of cancer risk, this study investigated how urinary 8‐OH‐dG was associated with occupational and lifestyle factors in 372 healthy workers. The creatinine‐adjusted urinary 8‐OH‐dG level was significantly higher in male subjects, smokers and drinkers compared with their counterparts. There were significant positive correlations of the 8‐OH‐dG level with average number of working hours, involvement in work, average number of cigarettes smoked, average volume of alcohol consumed and serum cortisol level, and there were significant negative correlations of the 8‐OH‐dG level with body mass index (BMI) and consumption of soybean products, rice and light‐colored vegetables. Multiple regression analysis showed that average number of working hours and average number of cigarettes smoked were significant predictors of increased 8‐OH‐dG levels, whereas being female and BMI were significant predictors of decreased 8‐OH‐dG levels. Working hours, BMI and smoking were significant predictors of urinary 8‐OH‐dG in male subjects, whereas age and BMI were significant predictors in female subjects. We suggest that several occupational and lifestyle factors, particularly long working hours and cigarette smoking, are linked to the formation of 8‐OH‐dG in workers. (Cancer Sci 2005; 96: 600 – 606)
ABSTRACT We search for electron anti-neutrinos ( ) from long- and short-duration gamma-ray bursts (GRBs) using data taken by the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND) from 2002 ...August to 2013 June. No statistically significant excess over the background level is found. We place the tightest upper limits on fluence from GRBs below 7 MeV and place first constraints on the relation between luminosity and effective temperature.
The removal of radioactivity from liquid scintillator has been studied in preparation of a low background phase of KamLAND. This paper describes the methods and techniques developed to measure and ...efficiently extract radon decay products from liquid scintillator. We report the radio-isotope reduction factors obtained when applying various extraction methods. During this study, distillation was identified as the most efficient method for removing radon-born lead from liquid scintillator.
We present two results of a search for MeV-scale neutrino and anti-neutrino events correlated with gravitational wave events/candidates and large solar flares with KamLAND. The KamLAND detector is a ...large-volume neutrino detector using liquid scintillator, which is located at 1 km underground under the top of Mt. Ikenoyama in Kamioka, Japan. KamLAND has multiple reaction channels to detect neutrinos. Electron antineutrino can be detected via inverse-beta decay with 1.8 MeV neutrino energy threshold. All flavors of neutrinos can be detected via neutrino-electron scattering without neutrino energy threshold. KamLAND has continued the neutrino observation since 2002 March. We use the data set of 60 gravitational waves provided by the LIGO/Virgo collaboration during their second and third observing runs and search for coincident electron antineutrino events in KamLAND. We find no significant coincident signals within a ±500 s timing window from each gravitational wave and present 90% C.L. upper limits on the electron antineutrino fluence between 108–1013 cm-2 for neutrino energies of 1.8–111 MeV. For a solar-flare neutrino search at KamLAND, we determine the timing window using the solar X-ray data set provided by the GOES satellite series from 2002 to 2019 and search for the excess of coincident event rate on the all-flavor neutrinos. We find no significant event rate excess in the flare time windows and get 90% C.L. upper limits on the fluence of neutrinos of all flavors (electron anti-neutrinos) between 1010–1013 cm-2 (108–1013 cm-2) for neutrino energies in the energy range of 0.4–35 MeV.
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