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[en] Here, 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.

[en] We developed radioimmunoassay to determine serum pregnancy-associated α₂-glycoprotein (SP₃) using the double antibody method. The determined value was accurate and reproducible. Serum SP₃ level in normal male was below 1.5mg/dl (n=20), in normal female was below 2.8 mg/dl (n=19). In 56.8 of patients with various cancer (n=81) (stomach, colon, lung and breast et al) serum SP₃ levels were over normal value. Especially 2 patients treated estrogen for their prostate cancer had high serum SP₃ levels. Serum SP₃ levels in cancer patients increased with the tumor progression, but there was no relation between SP₃ and CEA level. Determination of serum SP₃ by radioimmunoassay is available for detection of malignant tumor and tumor progression

[en] Recently, we have found the immunological similarity of CEA with α₁-acid glycoprotein (AG). In this study we want to describe the purification method of CEA by anti-AG chromatography and improved CEA-RIA using the purified CEA preparation as antigen. When RIA was performed by the purified CEA preparation (commercially available isotope-labelled CEA preparation was purified by affinity chromatography using anti-AG bound to Sepharose column), the sensitivity of the standard curve showed the significant improvement. The practical purification of CEA from tumor tissue by anti-AG chromatography was also possible. CEA purified by this method could be useful not only for the improvement of sensitivity of CEA-RIA but also for the international standartization of CEA

[en] The authors have demonstrated that ¹²⁵I-CEA (carcinoembryonic antigen) from two commerical sources (Roche and CIS RIA kit) can be precipitated by antibody to α₁-acid glycoprotein (AG) dose-dependently. The binding of ¹²⁵I-CEA to anti-AG can be displaced by unlabelled AG, though, there was no cross-reaction between AG and anti-CEA. The data strongly suggest that CEA has an immunological similarity to AG. The perchloric acid extract from cancerous tissue was fractionated on a Sephadex G-200 column, and the first eluted fraction (containing large amounts of CEA) was subjected to affinity chromatography using anti-AG bound to Sepharose. The bound fraction was eluted, labelled with ¹²⁵I, and then applied to a Sephadex G-200 column with carrier protein. The radioactivity was found mainly in the large molecular size eluted fraction (Fr 1). Almost all radioactivity of Fr 1 was precipitated by anti-AG and anti-CEA. This experiment also demonstrated that a large molecular weight component (Msub(r) 180000) obtained from tumour was immunologically related to both CEA and AG. Based on differences in binding affinities between CEA with anti-CEA and with anti-AG the authors postulate that CEA may be a large molecular precursor of AG (big form of AG). (Auth.)

[en] We search for electron anti-neutrinos (${\stackrel{¯<!--\; ??\; -->}{\mathrm{\nu <!--\; ??\; -->}}}_e$) 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 ${\stackrel{¯<!--\; ??\; -->}{\mathrm{\nu <!--\; ??\; -->}}}_e$ fluence from GRBs below 7 MeV and place first constraints on the relation between ${\stackrel{¯<!--\; ??\; -->}{\mathrm{\nu <!--\; ??\; -->}}}_e$ luminosity and effective temperature.

[en] In the late stages of nuclear burning for massive stars (M > 8 M_⊙), the production of neutrino–antineutrino pairs through various processes becomes the dominant stellar cooling mechanism. As the star evolves, the energy of these neutrinos increases and in the days preceding the supernova a significant fraction of emitted electron anti-neutrinos exceeds the energy threshold for inverse beta decay on free hydrogen. This is the golden channel for liquid scintillator detectors because the coincidence signature allows for significant reductions in background signals. We find that the kiloton-scale liquid scintillator detector KamLAND can detect these pre-supernova neutrinos from a star with a mass of 25 M_⊙ at a distance less than 690 pc with 3σ significance before the supernova. This limit is dependent on the neutrino mass ordering and background levels. KamLAND takes data continuously and can provide a supernova alert to the community

[en] We present the results of a search for MeV-scale electron antineutrino events in KamLAND coincident with the 60 gravitational wave events/candidates reported by the LIGO/Virgo collaboration during their second and third observing runs. 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 and 10¹³ cm⁻² for neutrino energies in the energy range of 1.8–111 MeV.

[en] A search for double-beta decays of "1"3"6Xe to excited states of "1"3"6Ba has been performed with the first phase data set of the KamLAND-Zen experiment. The 0_1"+ , 2_1"+ and 2_2"+ transitions of 0νββ decay were evaluated in an exposure of 89.5 kg•yr of "1"3"6Xe, while the same transitions of 2νββ decay were evaluated in an exposure of 61.8 kg•yr. No excess over background was found for all decay modes. The lower half-life limits of the 2_1"+ state transitions of 0νββ and 2νββ decay were improved to T((0v)/(1/2))(0"+ →2_1"+) > 2.6×10"2"5 yr and T((2v)/(1/2)) (0"+ →2_1"+) > 4.6×10"2"3 yr (90% C.L.), respectively. We report on the first experimental lower half-life limits for the transitions to the 0_1"+ state of "1"3"6Xe for 0νββ and 2νββ decay. They are T((0v)/(1/2))(0"+ →0_1"+) > 2.4×10"2"5 yr and T((2v)/(1/2))(0"+ →0_1"+) > 8.3×10"2"3 yr (90% C.L.). The transitions to the 2_2"+ states are also evaluated for the first time to be T((0v)/(1/2))(0"+ →2_2"+) > 2.6×10"2"5 yr and T((2v)/(1/2))(0"+ →2_2"+) > 9.0×10"2"3 yr (90% C.L.). Finally, these results are compared to recent theoretical predictions.

[en] The KamLAND-Zen 800 experiment is searching for the neutrinoless double-beta decay of ¹³⁶Xe by using ¹³⁶Xe-loaded liquid scintillator. The liquid scintillator is enclosed inside a balloon made of thin, transparent, low-radioactivity film that we call Inner Balloon (IB). The IB, apart from guaranteeing the liquid containment, also allows to minimize the background from cosmogenic muon-spallation products and ⁸B solar neutrinos. Indeed these events could contribute to the total counts in the region of interest around the Q-value of the double-beta decay of ¹³⁶Xe. In this paper, we present an overview of the IB and describe the various steps of its commissioning minimizing the radioactive contaminations, from the material selection, to the fabrication of the balloon and its installation inside the KamLAND detector. Finally, we show the impact of the IB on the KamLAND background as measured by the KamLAND detector itself. (paper)