Publications (76)
Search for the Majorana Nature of Neutrinos in the Inverted Mass Ordering Region with KamLAND-Zen
Zen Collaboration, S. Abe, S. Asami +70
The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta () decay half-life in Xe using a xenon-loaded liquid scintillator. We…
White paper: CeLAND - Investigation of the reactor antineutrino anomaly with an intense 144Ce-144Pr antineutrino source in KamLAND
A. Gando, Y. Gando, S. Hayashida +57
We propose to test for short baseline neutrino oscillations, implied by the recent reevaluation of the reactor antineutrino flux and by anomalous results from the gallium solar neu…
A search for correlated low-energy electron antineutrinos in KamLAND with gamma-ray bursts
S. Abe, S. Asami, A. Gando +64
We present the results of a time-coincident event search for low-energy electron antineutrinos in the KamLAND detector with gamma-ray bursts from the Gamma-ray Coordinates Network…
CeLAND: search for a 4th light neutrino state with a 3 PBq 144Ce-144Pr electron antineutrino generator in KamLAND
A. Gando, Y. Gando, S. Hayashida +63
The reactor neutrino and gallium anomalies can be tested with a 3-4 PBq (75-100 kCi scale) 144Ce-144Pr antineutrino beta-source deployed at the center or next to a large low-backgr…
Laboratory Studies on the Removal of Radon-Born Lead from KamLAND's Organic Liquid Scintillator
G. Keefer, C. Grant, A. Piepke +64
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 develope…
A simple model of reactor cores for reactor neutrino flux calculations for the KamLAND experiment
K. Nakajima, K. Inoue, K. Owada +6
KamLAND is a reactor neutrino oscillation experiment with a very long baseline. This experiment successfully measured oscillation phenomena of reactor antineutrinos coming mainly f…
Measurement of the 8B Solar Neutrino Flux with the KamLAND Liquid Scintillator Detector
KamLAND Collaboration, S. Abe, K. Furuno +77
We report a measurement of the neutrino-electron elastic scattering rate from 8B solar neutrinos based on a 123 kton-day exposure of KamLAND. The background-subtracted electron rec…
Measurement of He()H reaction cross section and evaluation of hypertriton binding energy
T. Akaishi, H. Asano, X. Chen +32
Light -shell hypernuclei () and their ground-state properties are crucial benchmarks in hypernuclear physics. In particular, comparing the production cross se…
Measurement of cosmic-ray muon spallation products in a xenon-loaded liquid scintillator with KamLAND
Zen Collaboration, S. Abe, S. Asami +63
Cosmic-ray muons produce various radioisotopes when passing through material. These spallation products can be backgrounds for rare event searches such as in solar neutrino, double…
Search for n-nbar oscillation in Super-Kamiokande
Kamiokande collaboration, K. Abe, Y. Hayato +135
A search for neutron-antineutron () oscillation was undertaken in Super-Kamiokande using the 1489 live-day or neutron-year exposure data. This proc…
Specific Heat Study of an S=1/2 Alternating Heisenberg Chain System F_5PNN Under Magnetic Field
Y. Yoshida, N. Tateiwa, M. Mito +4
We have measured the specific heat of an S=1/2 antiferromagnetic alternating Heisenberg chain pentafulorophenyl nitronyl nitroxide under magnetic fields up to H>H_C2. This compound…
KamLAND-PICO project to search for cosmic dark matter
K. Fushimi, Y. Awatani, H. Ejiri +8
KamLAND-PICO project aims to search for WIMPs dark matter by means of NaI(Tl) scintillator. To investigate the WIMPs candidate whose cross section is as small as pb, a pu…
Real-space renormalization group study of the anisotropic antiferromagnetic Heisenberg model of spin S=1 on a honeycomb lattice
A. S. Boyarchenkov, A. S. Ovchinnikov, I. G. Bostrem +3
The real-space RG approach is applied to study critical temperatures of system consisting of interacting spin chains of spin S=1 with an inner antiferromagnetic exchange which form…
Neutrino geophysics with KamLAND and future prospects
S. Enomoto, E. Ohtani, K. Inoue +1
The Kamioka liquid scintillator anti-neutrino detector (KamLAND) is a low-energy and low-background neutrino detector which could be a useful probe for determining the U and Th abu…
Letter of Intent: The Hyper-Kamiokande Experiment --- Detector Design and Physics Potential ---
K. Abe, T. Abe, H. Aihara +38
We propose the Hyper-Kamiokande (Hyper-K) detector as a next generation underground water Cherenkov detector. It will serve as a far detector of a long baseline neutrino oscillatio…
Limits on the Low-Energy Electron Antineutrino Flux from the Brightest GRB of All Time
T. Araki, S. Chauhan, K. Chiba +69
The electron antinuetrino flux limits are presented for the brightest gamma-ray burst (GRB) of all time, GRB221009A, over a range of 1.8-200 MeV using the Kamioka Liquid Scintillat…
Semiclassical properties and chaos degree for the quantum baker's map
K. Inoue, M. Ohya, I. V. Volovich
We study the chaotic behaviour and the quantum-classical correspondence for the baker's map. Correspondence between quantum and classical expectation values is investigated and it…
Search for electron antineutrinos associated with gravitational wave events GW150914 and GW151226 using KamLAND
KamLAND Collaboration, A. Gando, Y. Gando +45
We present a search for low energy antineutrino events coincident with the gravitational wave events GW150914 and GW151226, and the candidate event LVT151012 using KamLAND, a kilot…
Homogeneous and heterogeneous nucleation of skyrmions in thin layers of cubic helimagnets
A. O. Leonov, K. Inoue
Formation of isolated chiral skyrmions by homogeneous and heterogeneous nucleation has been studied in thin layers of cubic helimagnets via elongation of torons and chiral bobbers,…
On Quantum - Classical Correspondence for Baker's Map
K. Inoue, M. Ohya, I. V. Volovich
Quantum baker`s map is a model of chaotic system. We study quantum dynamics for the quantum baker's map. We use the Schack and Caves symbolic description of the quantum baker`s map…
Search for cosmic dark matter by means of ultra high purity NaI(Tl) scintillator
K. Fushimi, D. Chernyak, H. Ejiri +13
The dark matter search project by means of ultra high purity NaI(Tl) scintillator is now underdevelopment. An array of large volume NaI(Tl) detectors whose volume is 12.7 cm$Ï\tim…
The nylon balloon for xenon loaded liquid scintillator in KamLAND-Zen 800 neutrinoless double-beta decay search experiment
Zen collaboration, Y. Gando, A. Gando +70
The KamLAND-Zen 800 experiment is searching for the neutrinoless double-beta decay of Xe by using Xe-loaded liquid scintillator. The liquid scintillator is enclosed…
Search for Dark Matter WIMPs using Upward Through-going Muons in Super-Kamiokande
Kamiokande Collaboration, S. Desai, Y. Ashie +133
We present the results of indirect searches for Weakly Interacting Massive Particles (WIMPs) with 1679.6 live days of data from the Super-Kamiokande detector using neutrino-induced…
Quantum dissipation theory of slow magnetic relaxation mediated by domain-wall motion in one-dimensional chain compound [Mn(hfac)_{2}BNO_{H}}]
A. S. Ovchinnikov, I. G. Bostrem, V. E. Sinitsyn +3
Based on a quantum dissipation theory of open systems, we present a theoretical study of slow dynamics of magnetization for the ordered state of the new molecule-based magnetic com…
Magnetic-field and pressure phase diagram of the triangular lattice antiferromagnet CsCuCl clarified by magnetic susceptibility measured with a proximity detector oscillator
K. Nihongi, T. Kida, Y. Narumi +6
The effect of pressure () on magnetic susceptibility of CsCuCl was examined in magnetic fields () of up to 51 T using a proximity detector oscillator (PDO), and…
PICOLON dark matter search project
K. Fushimi, D. Chernyak, H. Ejiri +21
PICOLON (Pure Inorganic Crystal Observatory for LOw-energy Neutr(al)ino) aims to search for cosmic dark matter by high purity NaI(Tl) scintillator. We developed extremely pure NaI(…
A compact ultra-clean system for deploying radioactive sources inside the KamLAND detector
T. I. Banks, S. J. Freedman, J. Wallig +54
We describe a compact, ultra-clean device used to deploy radioactive sources along the vertical axis of the KamLAND liquid-scintillator neutrino detector for purposes of calibratio…
Abundances of uranium and thorium elements in Earth estimated by geoneutrino spectroscopy
S. Abe, S. Asami, M. Eizuka +64
The decay of the primordial isotopes , , , and have contributed to the terrestrial heat budget throughout t…
Limits on astrophysical antineutrinos with the KamLAND experiment
S. Abe, S. Asami, A. Gando +66
We report on a search for electron antineutrinos () from astrophysical sources in the neutrino energy range 8.3 to 30.8 MeV with the KamLAND detector. In an exposure of 6…
Dark matter search project PICO-LON
K. Fushimi, H. Ejiri, R. Hazama +12
The PICO-LON project aims at search for cold dark matter by means of highly radio-pure and large volume NaI(Tl) scintillator. The NaI powder was purifed by chemical processing to r…
Spin density distribution in a partially magnetized organic quantum magnet
A. Zheludev, V. O. Garlea, S. Nishihara +4
Polarized neutron diffraction experiments on an organic magnetic material reveal a highly skewed distribution of spin density within the magnetic molecular unit. The very large mag…
Neutrinoless Double Beta Decay
C. Adams, K. Alfonso, C. Andreoiu +229
This White Paper, prepared for the Fundamental Symmetries, Neutrons, and Neutrinos Town Meeting related to the 2023 Nuclear Physics Long Range Plan, makes the case for double beta…
Search for Low-energy Electron Antineutrinos in KamLAND Associated with Gravitational Wave Events
S. Abe, S. Asami, A. Gando +65
We present the results of a search for MeV-scale electron antineutrino events in KamLAND in coincident with the 60 gravitational wave events/candidates reported by the LIGO/Virgo c…
Dark matter search with high purity NaI(Tl) scintillator
K. Fushimi, Y. Kanemitsu, K. Kotera +21
A dark matter search project needs and extremely low background radiation detector since the expected event rate of dark matter is less than a few events in one year in one tonne o…
Chiral surface twists and skyrmion stability in nanolayers of cubic helimagnets
A. O. Leonov, Y. Togawa, T. L. Monchesky +15
Lorentz transmission electron microscopy (LTEM) investigations of modulated states in a FeGe wedge and detailed calculations demonstrate that chiral twists arising near the surface…
KamLAND's search for correlated low-energy electron antineutrinos with astrophysical neutrinos from IceCube
S. Abe, S. Asami, M. Eizuka +66
We report the results of a search for MeV-scale astrophysical neutrinos in KamLAND presented as an excess in the number of coincident neutrino interactions associated with the publ…
Search for Solar Flare Neutrinos with the KamLAND detector
S. Abe, S. Asami, A. Gando +65
We report the result of a search for neutrinos in coincidence with solar flares from the GOES flare database. The search was performed on a 10.8 kton-year exposure of KamLAND colle…
KamLAND Sensitivity to Neutrinos from Pre-Supernova Stars
K. Asakura, A. Gando, Y. Gando +44
In the late stages of nuclear burning for massive stars ($M>8~M_{\sun}$), the production of neutrino-antineutrino pairs through various processes becomes the dominant stellar cooli…
Search for supernova neutrinos and constraint on the galactic star formation rate with the KamLAND data
S. Abe, S. Asami, M. Eizuka +63
We present the results of a search for core-collapse supernova neutrinos, using long-term KamLAND data from 2002 March 9 to 2020 April 25. We focus on the electron antineutrinos em…
Physics Potential of a Long Baseline Neutrino Oscillation Experiment Using J-PARC Neutrino Beam and Hyper-Kamiokande
Hyper-Kamiokande Proto-Collaboraion, :, K. Abe +247
Hyper-Kamiokande will be a next generation underground water Cherenkov detector with a total (fiducial) mass of 0.99 (0.56) million metric tons, approximately 20 (25) times larger…
Study of electron anti-neutrinos associated with gamma-ray bursts using KamLAND
K. Asakura, A. Gando, Y. Gando +45
We search for electron anti-neutrinos () from long and short-duration gamma-ray bursts~(GRBs) using data taken by the KamLAND detector from August 2002 to June 2013.…
CANGAROO-III Observation of TeV Gamma Rays from the vicinity of PSR B1 706-44
R. Enomoto, J. Kushida, T. Nakamori +50
Observation by the CANGAROO-III stereoscopic system of the Imaging Cherenkov Telescope has detected extended emission of TeV gamma rays in the vicinity of the pulsar PSR B170644…
Magnetic hysteresis in a molecular Ising ferrimagnet: Glauber dynamics approach
A. A. Bukharov, A. S. Ovchinnikov, N. V. Baranov +1
Motivated by recent experimental results reporting giant coercive fields in Co(II)-based molecular magnets we present a theory of hysteresis phenomena based on the Glauber stochast…
RFSoC-based front-end electronics for pulse detection
S. N. Axani, S. Futagi, M. Garcia +12
Radiation measurement relies on pulse detection, which can be performed using various configurations of high-speed analog-to-digital converters (ADCs) and field-programmable gate a…
Precise measurement of using Japanese Reactors
F. Suekane, K. Inoue, T. Araki +1
After the KamLAND results, the remaining important targets in neutrino experiments are to measure still unknown 3 basic parameters; absolute neutrino mass scale, CP violation phase…
A Long Baseline Neutrino Oscillation Experiment Using J-PARC Neutrino Beam and Hyper-Kamiokande
Kamiokande Working Group, K. Abe, H. Aihara +245
Hyper-Kamiokande will be a next generation underground water Cherenkov detector with a total (fiducial) mass of 0.99 (0.56) million metric tons, approximately 20 (25) times larger…
First measurement of the strange axial coupling constant using neutral-current quasielastic interactions of atmospheric neutrinos at KamLAND
KamLAND Collaboration, S. Abe, S. Asami +61
We report a measurement of the strange axial coupling constant using atmospheric neutrino data at KamLAND. This constant is a component of the axial form factor of the neut…
Development of highly radiopure NaI(Tl) scintillator for PICOLON dark matter search project
K. Fushimi, Y. Kanemitsu, S. Hirata +20
The highly radiopure NaI(Tl) was developed to search for particle candidates of dark matter. The optimized methods were combined to reduce various radioactive impurities. The $^{40…
Pole position of measured in reactions
PARC E31 Collaboration, S. Aikawa, S. Ajimura +74
We measured a set of , , and invariant mass spectra below and above the mass threshold in -induced reactions on deuteron. We dedu…
Recent results and future prospects of kaonic nuclei at J-PARC
F. Sakuma, S. Ajimura, T. Akaishi +73
-nuclear bound systems, kaonic nuclei, have been widely discussed as products of the strongly attractive interaction in channels. Recently, we demonstrat…
A Search for Charged Excitation of Dark Matter with the KamLAND-Zen Detector
S. Abe, S. Asami, A. Gando +68
There are many theories where a dark matter particle is part of a multiplet with an electrically charged state. If WIMP dark matter () is accompanied by a charged excited s…
Kamland Results
K. Inoue
The LMA solution of the solar neutrino problem has been explored with the 1,000 ton liquid scinatillator detector, KamLAND. It utilizes nuclear power reactors distributing effectiv…
Constraints on neutrino oscillation parameters from the measurement of day-night solar neutrino fluxes at Super-Kamiokande
Kamiokande Collaboration, Y. Fukuda, T. Hayakawa +2
A search for day-night variations in the solar neutrino flux resulting from neutrino oscillations has been carried out using the 504 day sample of solar neutrino data obtained at S…
Limits on Majoron-emitting double-beta decays of Xe-136 in the KamLAND-Zen experiment
Zen Collaboration, A. Gando, Y. Gando +37
We present limits on Majoron-emitting neutrinoless double-beta decay modes based on an exposure of 112.3 days with 125 kg of Xe-136. In particular, a lower limit on the ordinary (s…
Magnetization and spin gap in two-dimensional organic ferrimagnet BIPNNBNO
V. E. Sinitsyn, I. G. Bostrem, A. S. Ovchinnikov +2
A magnetization process in two-dimensional ferrimagnet BIPNNBNO is analyzed. The compound consists of ferrimagnetic (1,1/2) chains coupled by two sorts of antiferromagnetic interac…
CANGAROO-III search for TeV Gamma-rays from two clusters of galaxies
R. Kiuchi, M. Mori, G. V. Bicknell +47
Because accretion and merger shocks in clusters of galaxies may accelerate particles to high energies, clusters are candidate sites for the origin of ultra-high-energy (UHE) cosmic…
Possible Magnetic Chirality in Optically Chiral Magnet [Cr(CN)][Mn()-pnH(HO)](HO) Probed by Muon Spin Rotation and Relaxation
K. Ohishi, W. Higemoto, A. Koda +5
Local magnetic fields in a molecule-based optically chiral magnet [Cr(CN)][Mn()-pnH(HO)](HO) (GN-S) and its enantiomer (GN-R) are studied by means of muon spin rotat…
Search for Majorana Neutrinos with the Complete KamLAND-Zen Dataset
S. Abe, T. Araki, K. Chiba +69
We present a search for neutrinoless double-beta () decay of Xe using the full \mbox{KamLAND-Zen 800} dataset with 745\,kg of enriched xenon, corresponding to an e…
Structure near ++ threshold in the in-flight He reaction
PARC E15 Collaboration, Y. Sada, S. Ajimura +69
To search for an S= -1 di-baryonic state which decays to , the reaction was studied at 1.0 GeV/. Unobserved neutrons were kinematically i…
Physics Potentials with the Second Hyper-Kamiokande Detector in Korea
Hyper-Kamiokande proto-collaboration, :, K. Abe +353
Hyper-Kamiokande consists of two identical water-Cherenkov detectors of total 520~kt with the first one in Japan at 295~km from the J-PARC neutrino beam with 2.5 Off…
Differential phase shift quantum key distribution experiment over 105 km fibre
H. Takesue, E. Diamanti, T. Honjo +4
Since several papers appeared in 2000, the quantum key distribution (QKD) community has been well aware that photon number splitting (PNS) attack by Eve severely limits the secure…
Measurement of the strong interaction induced shift and width of the 1s state of kaonic deuterium at J-PARC
J. Zmeskal, M. Sato, S. Ajimura +74
The antikaon-nucleon interaction close to threshold provides crucial information on the interplay between spontaneous and explicit chiral symmetry breaking in low-energy QCD. In th…
Background stability and annual modulation test using PICOLON ultra-pure NaI(Tl) detector
PICOLON Collaboration, K. Kotera, D. Chernyak +20
The dark matter observation claimed by the DAMA/LIBRA experiment has been a long-standing puzzle within the particle physics community. NaI(Tl) crystals with radiopurity comparable…
Search for double-beta decay of 136Xe to excited states of 136Ba with the KamLAND-Zen experiment
Zen Collaboration, K. Asakura, A. Gando +42
A search for double-beta decays of 136Xe to excited states of 136Ba has been performed with the first phase data set of the KamLAND-Zen experiment. The 0+1, 2+1 and 2+2 transitions…
Supernova Model Discrimination with Hyper-Kamiokande
Kamiokande Collaboration, K. Abe, P. Adrich +499
Core-collapse supernovae are among the most magnificent events in the observable universe. They produce many of the chemical elements necessary for life to exist and their remnants…
Observation of a bound state in the reaction
T. Yamaga, S. Ajimura, H. Asano +66
We have performed an exclusive measurement of the reaction at an incident kaon momentum of .In the invariant mass spectrum,…
Radiopurity of NaI(Tl) crystals for PICOLON dark matter experiment
K. Kotera, D. Chernyak, H. Ejiri +19
The dark matter observation claim by the DAMA/LIBRA collaboration has been a long-standing puzzle within the particle physics community. Efforts of other research groups to verify…
Measurement of the mesonic decay branch of the quasi-bound state
T. Yamaga, S. Ajimura, H. Asano +67
We conducted measurements of reactions using a -beam, with the objective of understanding the broad decay width of $\ba…
Search for Diffuse Supernova Neutrino Background in the Full KamLAND Dataset with Neural-Network-Based Event Classification
D. Chernyak, T. Eda, M. Eizuka +63
We report a search for the diffuse supernova neutrino background (DSNB) with the KamLAND detector, targeting electron antineutrinos via inverse beta decay in the neutrino energy ra…
Reactor Measurement of and Its Complementarity to Long-Baseline Experiments
H. Minakata, H. Sugiyama, O. Yasuda +2
A possibility to measure using reactor neutrinos is examined in detail. It is shown that the sensitivity can be reached with 20 ton-year data…
Present status of PICOLON project
K. Fushimi, D. Chernyak, H. Ejiri +24
The existence of cosmic dark matter and neutrino properties are long-standing problems in cosmology and particle physics. These problems have been investigated by using radiation d…
Precise lifetime measurement of H hypernucleus using in-flight HeH reaction
T. Akaishi, H. Asano, X. Chen +35
We present a new measurement of the H hypernuclear lifetime using in-flight + He H + reaction at the J-PARC hadron facility. We demonst…
"", a -Meson Nuclear Bound State, Observed in Reactions
PARC E15 collaboration, S. Ajimura, H. Asano +67
We observed a distinct peak in the invariant mass spectrum of , well below the mass threshold of . By selecting a relatively large mo…
Search for Charged Excited States of Dark Matter with KamLAND-Zen
Zen collaboration, S. Abe, M. Eizuka +64
Particle dark matter could belong to a multiplet that includes an electrically charged state. WIMP dark matter () accompanied by a negatively charged excited state ($Ï^{-}…
Hyper-Kamiokande Design Report
Hyper-Kamiokande Proto-Collaboration, :, K. Abe +313
On the strength of a double Nobel prize winning experiment (Super)Kamiokande and an extremely successful long baseline neutrino programme, the third generation Water Cherenkov dete…
7Be Solar Neutrino Measurement with KamLAND
A. Gando, Y. Gando, H. Hanakago +68
We report a measurement of the neutrino-electron elastic scattering rate of 862 keV 7Be solar neutrinos based on a 165.4 kton-day exposure of KamLAND. The observed rate is 582 +/-…