The Experts below are selected from a list of 108495 Experts worldwide ranked by ideXlab platform
Hiroshi Sudou - One of the best experts on this subject based on the ideXlab platform.
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a very close binary black hole in a giant elliptical galaxy 3c 66b and its black hole merger
The Astrophysical Journal, 2010Co-Authors: Satoru Iguchi, Takeshi Okuda, Hiroshi SudouAbstract:Recent observational results provide possible evidence that binary black holes (BBHs) exist in the center of giant galaxies and may merge to form a supermassive black hole in the process of their evolution. We first detected a Periodic flux variation on a cycle of 93 ± 1 days from the 3 mm monitor observations of a giant elliptical galaxy 3C 66B for which an orbital motion with a Period of 1.05 ± 0.03 yr had been already observed. The detected Signal Period being shorter than the orbital Period can be explained by taking into consideration the Doppler-shifted modulation due to the orbital motion of a BBH. Assuming that the BBH has a circular orbit and that the jet axis is parallel to the binary angular momentum, our observational results demonstrate the presence of a very close BBH that has a binary orbit with an orbital Period of 1.05 ± 0.03 yr, an orbital radius of (3.9 ± 1.0) × 10–3 pc, an orbital separation of (6.1+1.0 –0.9) × 10–3 pc, a larger black hole mass of (1.2+0.5 –0.2) × 109 M ☉, and a smaller black hole mass of (7.0+4.7 –6.4) × 108 M ☉. The BBH decay time of (5.1+60.5 –2.5) × 102 yr provides evidence for the occurrence of black hole mergers. This Letter will demonstrate the interesting possibility of black hole collisions to form a supermassive black hole in the process of evolution, one of the most spectacular natural phenomena in the universe.
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a very close binary black hole in a giant elliptical galaxy 3c 66b and its black hole merger
arXiv: Astrophysics of Galaxies, 2010Co-Authors: Satoru Iguchi, Takeshi Okuda, Hiroshi SudouAbstract:Recent observational results provide possible evidence that binary black holes (BBHs) exist in the center of giant galaxies and may merge to form a supermassive black hole in the process of their evolution. We first detected a Periodic flux variation on a cycle of $93\pm1$ days from the 3-mm monitor observations of a giant elliptical galaxy \object{3C 66B} for which an orbital motion with a Period of $1.05\pm0.03$ years had been already observed. The detected Signal Period being shorter than the orbital Period can be explained by taking into consideration the Doppler-shifted modulation due to the orbital motion of a BBH. Assuming that the BBH has a circular orbit and that the jet axis is parallel to the binary angular momentum, our observational results demonstrate the presence of a very close BBH that has the binary orbit with an orbital Period of $1.05\pm0.03$ years, an orbital radius of $(3.9\pm1.0) \times 10^{-3}$ pc, an orbital separation of $(6.1^{+1.0}_{-0.9}) \times 10^{-3}$ pc, the larger black hole mass of $(1.2^{+0.5}_{-0.2}) \times 10^9$ $M_{\sun}$, and the smaller black hole mass of $(7.0^{+4.7}_{-6.4}) \times 10^8$ $M_{\sun}$. The BBH decay time of $(5.1^{+60.5}_{-2.5})\times 10^2$ years provides evidence for the occurrence of black hole mergers. This Letter will demonstrate the interesting possibility of black hole collisions to form a supermassive black hole in the process of evolution, one of the most spectacular natural phenomena in the universe.
Satoru Iguchi - One of the best experts on this subject based on the ideXlab platform.
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a very close binary black hole in a giant elliptical galaxy 3c 66b and its black hole merger
The Astrophysical Journal, 2010Co-Authors: Satoru Iguchi, Takeshi Okuda, Hiroshi SudouAbstract:Recent observational results provide possible evidence that binary black holes (BBHs) exist in the center of giant galaxies and may merge to form a supermassive black hole in the process of their evolution. We first detected a Periodic flux variation on a cycle of 93 ± 1 days from the 3 mm monitor observations of a giant elliptical galaxy 3C 66B for which an orbital motion with a Period of 1.05 ± 0.03 yr had been already observed. The detected Signal Period being shorter than the orbital Period can be explained by taking into consideration the Doppler-shifted modulation due to the orbital motion of a BBH. Assuming that the BBH has a circular orbit and that the jet axis is parallel to the binary angular momentum, our observational results demonstrate the presence of a very close BBH that has a binary orbit with an orbital Period of 1.05 ± 0.03 yr, an orbital radius of (3.9 ± 1.0) × 10–3 pc, an orbital separation of (6.1+1.0 –0.9) × 10–3 pc, a larger black hole mass of (1.2+0.5 –0.2) × 109 M ☉, and a smaller black hole mass of (7.0+4.7 –6.4) × 108 M ☉. The BBH decay time of (5.1+60.5 –2.5) × 102 yr provides evidence for the occurrence of black hole mergers. This Letter will demonstrate the interesting possibility of black hole collisions to form a supermassive black hole in the process of evolution, one of the most spectacular natural phenomena in the universe.
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a very close binary black hole in a giant elliptical galaxy 3c 66b and its black hole merger
arXiv: Astrophysics of Galaxies, 2010Co-Authors: Satoru Iguchi, Takeshi Okuda, Hiroshi SudouAbstract:Recent observational results provide possible evidence that binary black holes (BBHs) exist in the center of giant galaxies and may merge to form a supermassive black hole in the process of their evolution. We first detected a Periodic flux variation on a cycle of $93\pm1$ days from the 3-mm monitor observations of a giant elliptical galaxy \object{3C 66B} for which an orbital motion with a Period of $1.05\pm0.03$ years had been already observed. The detected Signal Period being shorter than the orbital Period can be explained by taking into consideration the Doppler-shifted modulation due to the orbital motion of a BBH. Assuming that the BBH has a circular orbit and that the jet axis is parallel to the binary angular momentum, our observational results demonstrate the presence of a very close BBH that has the binary orbit with an orbital Period of $1.05\pm0.03$ years, an orbital radius of $(3.9\pm1.0) \times 10^{-3}$ pc, an orbital separation of $(6.1^{+1.0}_{-0.9}) \times 10^{-3}$ pc, the larger black hole mass of $(1.2^{+0.5}_{-0.2}) \times 10^9$ $M_{\sun}$, and the smaller black hole mass of $(7.0^{+4.7}_{-6.4}) \times 10^8$ $M_{\sun}$. The BBH decay time of $(5.1^{+60.5}_{-2.5})\times 10^2$ years provides evidence for the occurrence of black hole mergers. This Letter will demonstrate the interesting possibility of black hole collisions to form a supermassive black hole in the process of evolution, one of the most spectacular natural phenomena in the universe.
Takeshi Okuda - One of the best experts on this subject based on the ideXlab platform.
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a very close binary black hole in a giant elliptical galaxy 3c 66b and its black hole merger
The Astrophysical Journal, 2010Co-Authors: Satoru Iguchi, Takeshi Okuda, Hiroshi SudouAbstract:Recent observational results provide possible evidence that binary black holes (BBHs) exist in the center of giant galaxies and may merge to form a supermassive black hole in the process of their evolution. We first detected a Periodic flux variation on a cycle of 93 ± 1 days from the 3 mm monitor observations of a giant elliptical galaxy 3C 66B for which an orbital motion with a Period of 1.05 ± 0.03 yr had been already observed. The detected Signal Period being shorter than the orbital Period can be explained by taking into consideration the Doppler-shifted modulation due to the orbital motion of a BBH. Assuming that the BBH has a circular orbit and that the jet axis is parallel to the binary angular momentum, our observational results demonstrate the presence of a very close BBH that has a binary orbit with an orbital Period of 1.05 ± 0.03 yr, an orbital radius of (3.9 ± 1.0) × 10–3 pc, an orbital separation of (6.1+1.0 –0.9) × 10–3 pc, a larger black hole mass of (1.2+0.5 –0.2) × 109 M ☉, and a smaller black hole mass of (7.0+4.7 –6.4) × 108 M ☉. The BBH decay time of (5.1+60.5 –2.5) × 102 yr provides evidence for the occurrence of black hole mergers. This Letter will demonstrate the interesting possibility of black hole collisions to form a supermassive black hole in the process of evolution, one of the most spectacular natural phenomena in the universe.
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a very close binary black hole in a giant elliptical galaxy 3c 66b and its black hole merger
arXiv: Astrophysics of Galaxies, 2010Co-Authors: Satoru Iguchi, Takeshi Okuda, Hiroshi SudouAbstract:Recent observational results provide possible evidence that binary black holes (BBHs) exist in the center of giant galaxies and may merge to form a supermassive black hole in the process of their evolution. We first detected a Periodic flux variation on a cycle of $93\pm1$ days from the 3-mm monitor observations of a giant elliptical galaxy \object{3C 66B} for which an orbital motion with a Period of $1.05\pm0.03$ years had been already observed. The detected Signal Period being shorter than the orbital Period can be explained by taking into consideration the Doppler-shifted modulation due to the orbital motion of a BBH. Assuming that the BBH has a circular orbit and that the jet axis is parallel to the binary angular momentum, our observational results demonstrate the presence of a very close BBH that has the binary orbit with an orbital Period of $1.05\pm0.03$ years, an orbital radius of $(3.9\pm1.0) \times 10^{-3}$ pc, an orbital separation of $(6.1^{+1.0}_{-0.9}) \times 10^{-3}$ pc, the larger black hole mass of $(1.2^{+0.5}_{-0.2}) \times 10^9$ $M_{\sun}$, and the smaller black hole mass of $(7.0^{+4.7}_{-6.4}) \times 10^8$ $M_{\sun}$. The BBH decay time of $(5.1^{+60.5}_{-2.5})\times 10^2$ years provides evidence for the occurrence of black hole mergers. This Letter will demonstrate the interesting possibility of black hole collisions to form a supermassive black hole in the process of evolution, one of the most spectacular natural phenomena in the universe.
Hongzhong Liu - One of the best experts on this subject based on the ideXlab platform.
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Electronic Interpolation Interface Based on Linear Subdivision Method for Sinusoidal Optical Encoders
IEEE Sensors Journal, 2020Co-Authors: Zhao Guobo, Liu Hui, Biao Lei, Han Weiliang, Hongzhong LiuAbstract:Sinusoidal optical encoders are widely utilized in precision positioning systems. With the development of precision positioning systems, higher resolution is required. Electronic interpolation is a promising technique to further improve the resolution of sinusoidal optical encoders. In this paper, we propose an electronic interpolation interface based on linear subdivision method with better practical accuracy. Firstly, a pseudo-linearized Signal based on the difference between the absolute values of sine and cosine Signals is generated. Then, a compensation Signal with a ratiometric form is constructed, which has a better robustness to the non-ideal input Signals. Finally, a nearly perfect linear output Signal is obtained by combining these two Signals. Thus, the displacement can be linearly determined without LUTs. It is shown that the theoretical nonlinear error of the proposed method is below 0.08° over a Signal Period of 360°, which corresponds to a theoretical interpolation error of $0.018~\mu \text{m}$ for sinusoidal optical encoders with a pitch of $80~\mu \text{m}$ . Moreover, theoretical analysis and simulation results indicate that the proposed method offers a better practical accuracy. In the experiment, the proposed electronic interpolation interface is developed in a field-programmable gate array (FPGA), and experiments are carried out to evaluate its performance. Both the theoretical and experiment results verify its effectiveness.
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Ratiometric-Linearization-Based High-Precision Electronic Interpolator for Sinusoidal Optical Encoders
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Hongzhong Liu, Biao Lei, Yongsheng Shi, Yang Wang, Lei YinAbstract:Electronic interpolation is the key technology for further improving the measurement resolution of optical encoders. In this paper, an electronic interpolator based on the ratiometric linearization conversion method is presented. The proposed method converts the sinusoidal encoder Signals into a nearly perfectly linear output Signal through mathematical manipulation that only involves basic operations of addition, subtraction, multiplication, and division. Thus, the displacement can be precisely determined using a simple linear equation. Furthermore, quadrature interpolation pulses are also generated from the linear output Signal by using the amplitude subdivision method. Since the linearization procedure is based on the ratiometric operation, interpolation accuracy is independent of amplitude fluctuation of the encoder Signals. Theoretical analysis shows that the nonlinear error of the proposed interpolator is below ±0.0034 rad over a Signal Period of 2 π rad, which corresponds to an interpolation error of ±0.0108 μ m for a linear optical encoder with a pitch of 20 μ m. In the experiment, the proposed strategy is successfully implemented within a field programmable gate array, and applied to a 20 μ m-pitch optical encoder. Experiments are performed to demonstrate the effectiveness of the proposed method.
Lei Yin - One of the best experts on this subject based on the ideXlab platform.
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Ratiometric-Linearization-Based High-Precision Electronic Interpolator for Sinusoidal Optical Encoders
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Hongzhong Liu, Biao Lei, Yongsheng Shi, Yang Wang, Lei YinAbstract:Electronic interpolation is the key technology for further improving the measurement resolution of optical encoders. In this paper, an electronic interpolator based on the ratiometric linearization conversion method is presented. The proposed method converts the sinusoidal encoder Signals into a nearly perfectly linear output Signal through mathematical manipulation that only involves basic operations of addition, subtraction, multiplication, and division. Thus, the displacement can be precisely determined using a simple linear equation. Furthermore, quadrature interpolation pulses are also generated from the linear output Signal by using the amplitude subdivision method. Since the linearization procedure is based on the ratiometric operation, interpolation accuracy is independent of amplitude fluctuation of the encoder Signals. Theoretical analysis shows that the nonlinear error of the proposed interpolator is below ±0.0034 rad over a Signal Period of 2 π rad, which corresponds to an interpolation error of ±0.0108 μ m for a linear optical encoder with a pitch of 20 μ m. In the experiment, the proposed strategy is successfully implemented within a field programmable gate array, and applied to a 20 μ m-pitch optical encoder. Experiments are performed to demonstrate the effectiveness of the proposed method.
