86 citations · 157 across the 13 of their papers we have counts for
13 papers
Temperature dependence of broadband seismometer sensitivity
Tomofumi Shimoda, Wataru Kokuyama, Hideaki Nozato
Broadband seismometers are widely used in global observation networks deployed for geophysics research. Recently, the calibration of their sensitivity has become an important facto…
Accurate laboratory testing of low-frequency triaxial vibration sensors under various environmental conditions
Tomofumi Shimoda, Wataru Kokuyama, Hideaki Nozato
Triaxial vibration sensor are widely used used in various application. Recently, low-cost sensors based on micro electro mechanical system (MEMS) technology are also becoming more…
Optical sound pressure measurement using Fabry-Pérot cavity for primary acoustic standards
Koto Hirano, Wataru Kokuyama, Hajime Inaba +5
Optical sound pressure measurement is a promising technology to establish primary acoustic standards without reliance on specific types of microphones. We developed a precision opt…
Measurement of the intrinsic sensitivity for a single-ended accelerometer without the influence of the mounting condition
Tomofumi Shimoda, Wataru Kokuyama, Hideaki Nozato
The calibration technique for accelerometers has been internationally developed for up to 20 kHz to ensure the reliability of vibration measurement. However, it has been establishe…
TOrsion-Bar Antenna: A Ground-Based Detector for Low-Frequency Gravity Gradient Measurement
Satoru Takano, Tomofumi Shimoda, Yuka Oshima +12
The Torsion-Bar Antenna (TOBA) is a torsion pendulum-based gravitational detector developed to observe gravitational waves in frequencies between 1 mHz and 10 Hz. The low resonant…
Primary accelerometer calibration with two-axis automatic positioning stage
Wataru Kokuyama, Tomofumi Shimoda, Hideaki Nozato
In this study, we developed an automated, multipoint primary accelerometer calibration system using a two-axis positioning stage and a heterodyne laser interferometer. The proposed…
Precise sinusoidal signal extraction from noisy waveform in vibration calibration
Tomofumi Shimoda, Wataru Kokuyama, Hideaki Nozato
Precise extraction of sinusoidal vibration parameters is essential for the dynamic calibration of vibration sensors, such as accelerometers. However, several standard methods have…
Compact integrated optical sensors and electromagnetic actuators for vibration isolation systems in the gravitational-wave detector KAGRA
Tomotada Akutsu, Fabián Erasmo Peña Arellano, Ayaka Shoda +18
This paper reports on the design and characteristics of a compact module integrating an optical displacement sensor and an electromagnetic actuator for use with vibration-isolation…
Torsion-bar antenna: a ground-based mid-frequency and low-frequency gravitational wave detector
Tomofumi Shimoda, Satoru Takano, Ching Pin Ooi +4
Expanding the observational frequency of gravitational waves is important for the future of astronomy. Torsion-Bar Antenna (TOBA) is a mid-frequency and low-frequency gravitational…
Nonlinear vibration transfer in torsion pendulums
Tomofumi Shimoda, Masaki Ando
Torsion pendulums have been widely used in physical experiments, because their small restoring forces are suitable for tiny force measurement. Recently, some applications such as l…
Seismic Cross-coupling Noise in Torsion Pendulums
Tomofumi Shimoda, Naoki Aritomi, Ayaka Shoda +2
Detection of low frequency gravitational waves around 0.1 Hz is one of the important targets for future gravitational wave observation. One of the main sources of the expected sign…
Construction of KAGRA: an Underground Gravitational Wave Observatory
T. Akutsu, M. Ando, S. Araki +222
Major construction and initial-phase operation of a second-generation gravitational-wave detector KAGRA has been completed. The entire 3-km detector is installed underground in a m…
Mirror actuation design for the interferometer control of the KAGRA gravitational wave telescope
Yuta Michimura, Tomofumi Shimoda, Takahiro Miyamoto +36
KAGRA is a 3-km cryogenic interferometric gravitational wave telescope located at an underground site in Japan. In order to achieve its target sensitivity, the relative positions o…