National Defense Academy of Japan

About: National Defense Academy of Japan is a education organization based out in Yokosuka, Japan. It is known for research contribution in the topics: Antenna (radio) & Robot. The organization has 548 authors who have published 959 publications receiving 13457 citations. The organization is also known as: Bōei Daigakkō.

Japanese evaluated nuclear data library version 3 revision-3: JENDL-3.3

Abstract: The revision work of JENDL-3 has been made by considering feedback information of various benchmark tests. The main revised quantities are the resonance parameters, capture and inelastic scattering cross sections, and fission spectra of main actinide nuclides, the total and inelastic scattering cross sections of structural materials, the resonance parameters the capture and inelastic scattering cross sections of fission products, and the γ-ray production data. The revised data were released as JENDL-3.2 in June 1994. The preliminary benchmark tests indicate that JENDL-3.2 predicts various reactor characteristics more successfully than the previous version of JENDL-3.1.

Prospects for Observing and Localizing Gravitational-Wave Transients with Advanced LIGO, Advanced Virgo and KAGRA

Abstract: We present possible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitational-wave transients, with particular focus on gravitational-wave signals from the inspiral of binary neutron star systems, which are the most promising targets for multi-messenger astronomy. The ability to localize the sources of the detected signals depends on the geographical distribution of the detectors and their relative sensitivity, and 90% credible regions can be as large as thousands of square degrees when only two sensitive detectors are operational. Determining the sky position of a significant fraction of detected signals to areas of 5– 20 deg2 requires at least three detectors of sensitivity within a factor of ∼2 of each other and with a broad frequency bandwidth. When all detectors, including KAGRA and the third LIGO detector in India, reach design sensitivity, a significant fraction of gravitational-wave signals will be localized to a few square degrees by gravitational-wave observations alone.

Circulation on the north central Chukchi Sea shelf

Abstract: Mooring and shipboard data collected between 1992 and 1995 delineate the circulation over the north central Chukchi shelf. Previous studies indicated that Pacific waters crossed the Chukchi shelf through Herald Valley (in the west) and Barrow Canyon (in the east). We find a third branch (through the Central Channel) onto the outer shelf. The Central Channel transport varies seasonally in phase with Bering Strait transport, and is ∼0.2 Sv on average, although some of this might include water entrained from the outflow through Herald Valley. A portion of the Central Channel outflow moves eastward and converges with the Alaskan Coastal Current at the head of Barrow Canyon. The remainder appears to continue northeastward over the central outer shelf toward the shelfbreak, joined by outflow from Herald Valley. The mean flow opposes the prevailing winds and is primarily forced by the sea-level slope between the Pacific and Arctic oceans. Current variations are mainly wind forced, but baroclinic forcing, associated with upstream dense-water formation in coastal polynyas might occasionally be important. Winter water-mass modification depends crucially on the fall and winter winds, which control seasonal ice development. An extensive fall ice cover delays cooling, limits new ice formation, and results in little salinization. In such years, Bering shelf waters cross the Chukchi shelf with little modification. In contrast, extensive open water in fall leads to early and rapid cooling, and if accompanied by vigorous ice production within coastal polynyas, results in the production of high-salinity (>33) shelf waters. Such interannual variability likely affects slope processes and the transport of Pacific waters into the Arctic Ocean interior.

Observation of Gravitational Waves from Two Neutron Star–Black Hole Coalescences

Abstract: We report the observation of gravitational waves from two compact binary coalescences in LIGO’s and Virgo’s third observing run with properties consistent with neutron star–black hole (NSBH) binaries. The two events are named GW200105_162426 and GW200115_042309, abbreviated as GW200105 and GW200115; the first was observed by LIGO Livingston and Virgo and the second by all three LIGO–Virgo detectors. The source of GW200105 has component masses 8.9−1.5+1.2 and 1.9−0.2+0.3M⊙ , whereas the source of GW200115 has component masses 5.7−2.1+1.8 and 1.5−0.3+0.7M⊙ (all measurements quoted at the 90% credible level). The probability that the secondary’s mass is below the maximal mass of a neutron star is 89%–96% and 87%–98%, respectively, for GW200105 and GW200115, with the ranges arising from different astrophysical assumptions. The source luminosity distances are 280−110+110 and 300−100+150Mpc , respectively. The magnitude of the primary spin of GW200105 is less than 0.23 at the 90% credible level, and its orientation is unconstrained. For GW200115, the primary spin has a negative spin projection onto the orbital angular momentum at 88% probability. We are unable to constrain the spin or tidal deformation of the secondary component for either event. We infer an NSBH merger rate density of 45−33+75Gpc−3yr−1 when assuming that GW200105 and GW200115 are representative of the NSBH population or 130−69+112Gpc−3yr−1 under the assumption of a broader distribution of component masses.