Curriculum Vitaes
Profile Information
- Affiliation
- Assistant Professor, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
- Degree
- 博士 (理学)(Mar, 2020, 東京大学)修士 (理学)(Mar, 2017, 東京大学)
- Researcher number
- 30881213
- ORCID ID
https://orcid.org/0000-0001-6426-7079- J-GLOBAL ID
- 202001006174951270
- researchmap Member ID
- R000002942
Research Interests
6Research Areas
2Research History
3-
Jan, 2023 - Jun, 2025
Major Awards
6-
Mar, 2019
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Mar, 2017
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Mar, 2015
Papers
47-
Classical and Quantum Gravity, 41(21) 215013-215013, Oct 10, 2024 Peer-reviewedAbstract A series of quantum locking theories have been proposed to enhance the quantum-noise-limited target sensitivity of the DECi-hertz Interferometer Gravitational wave Observatory. The quantum locking that uses a square completion optimizes the sensitivity across all frequencies. However, a substantial amount of data-series must be post-processed since the square completion is a form of signal processing technique. This paper approaches the optimal sensitivity across all frequencies from an alternative perspective: by optimizing the frequency dependence of a servo gain in a feedback loop. The optimal servo gain is formulated by comparing the alternative method with the square completion method for the same optical setup. This will be shown in general noise issues extending the framework of the quantum locking. We find that the optimal servo gain forms a non-feasible filter but has certain characteristics. We also find that the noise of the measurement signal deteriorates proportionally to the noise measured in the feedback loop when the servo gain is slightly imperfect.
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Physical Review A, 110(2), Aug 1, 2024 Peer-reviewed
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Optics Express, May 2, 2024
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Physical Review Research, 5(4), Oct, 2023
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Physical Review Letters, Jul 25, 2023
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Physical Review D, 107(2) 022007, Jan 19, 2023Decihertz Interferometer Gravitational Wave Observatory (DECIGO) is a future mission for a space-borne laser interferometer. DECIGO has 1000-km-long arm cavities mainly to detect the primordial gravitational waves (PGWs) at lower frequencies around 0.1 Hz. Observations in the electromagnetic spectrum have lowered the bounds on the upper limit of PGWs energy density (Ω_(gw) ∼ 10⁻¹⁵ → 10⁻¹⁶). As a result, DECIGO’s target sensitivity, which is mainly limited by quantum noise, needs further improvement. To maximize the feasibility of detection while constrained by DECIGO’s large diffraction loss, a quantum locking technique with an optical spring was theoretically proposed to improve the signal-to-noise ratio of the PGWs. In this paper, we experimentally verify one key element used in the theory: sensitivity optimization by completing the square of multiple detector outputs. This experiment is operated on a simplified tabletop optical setup with classical noise simulating quantum noise. We succeed in getting the best of the sensitivities with two different laser powers by the square completion method.
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Physics Letters A, 453 128485, Nov 29, 2022Radiation pressure (RP) noise, one component of quantum noise, can limit the sensitivity of laser interferometric gravitational wave (GW) detectors at lower frequencies. We conceived a possible RP noise cancellation method, using phase flipped ponderomotive-squeezed light (FPSL) incident on free-mass mirrors in interferometers' arms. This possibility is investigated under the constraint that the method is for space-based GW detectors in a broad frequency band lower than 1 Hz without using a long optical cavity. Considering various patterns in a single path small-scale case to generate the FPSL, we proved that no configuration exists in the single path case.
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The Fifteenth Marcel Grossmann Meeting, 1599-1605, Jun 22, 2022
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Journal of the Optical Society of America A, 39(5) 969-969, May 1, 2022
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Applied Optics, 61(13) 3901-3901, May 1, 2022
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Quantum Approximate Optimization for Continuous Problems on a Programmable Photonic Quantum ComputerOptics InfoBase Conference Papers, 2022
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Science Advances, 7(46) eabj6624, Nov 12, 2021 Peer-reviewedLead author
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Physical Review A, 104(3), Sep 2, 2021
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The Astrophysical Journal Letters, 915(1) L5-L5, Jul 1, 2021Abstract 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 $1.{9}_{-0.2}^{+0.3}\,{M}_{\odot }$, whereas the source of GW200115 has component masses $5.{7}_{-2.1}^{+1.8}$ and $1.{5}_{-0.3}^{+0.7}\,{M}_{\odot }$ (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 ${300}_{-100}^{+150}\,\mathrm{Mpc}$, 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 ${45}_{-33}^{+75}\,{\mathrm{Gpc } }^{-3}\,{\mathrm{yr } }^{-1}$ when assuming that GW200105 and GW200115 are representative of the NSBH population or ${130}_{-69}^{+112}\,{\mathrm{Gpc } }^{-3}\,{\mathrm{yr } }^{-1}$ under the assumption of a broader distribution of component masses.
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Physical Review Letters, 126(24), Jun 16, 2021
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The Astrophysical Journal Letters, 913(2) L27-L27, Jun 1, 2021
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Physics Letters A, 402 127365-127365, Jun, 2021
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Progress of Theoretical and Experimental Physics, 2021(5), May 18, 2021
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Progress of Theoretical and Experimental Physics, 2021(5), May 18, 2021<jats:title>Abstract</jats:title> <jats:p>KAGRA is a newly build gravitational wave observatory, a laser interferometer with 3 km arm length, located in Kamioka, Gifu, Japan. In this paper, one of a series of articles featuring KAGRA, we discuss the science targets of KAGRA projects, considering not only the baseline KAGRA (current design) but also its future upgrade candidates (KAGRA+) for the near to middle term ($\sim$5 years).</jats:p>
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Progress of Theoretical and Experimental Physics, 2021(5), May 18, 2021
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Classical and Quantum Gravity, 38(8) 085013-085013, Apr 22, 2021Abstract We report the mirror suspension design for large-scale cryogenic gravitational wave telescope, KAGRA, during bKAGRA phase 1. Mirror thermal noise is one of the fundamental noises for room-temperature gravitational-wave detectors such as Advanced LIGO and Advanced Virgo. Thus, reduction of thermal noise is required for further improvement of their sensitivity. One effective approach for reducing thermal noise is to cool the mirrors. There are many technical challenges that must be overcome to cool the mirrors, such as cryocooler induced vibrations, thermal drift in suspensions, and reduction in duty cycling due to the increased number of potential failure mechanisms. Our mirror suspension has a black coating that makes radiative cooling more efficient. For conduction cooling, we developed ultra high purity aluminum heat links, which yield high thermal conductivity while keeping the spring constant sufficiently small. A unique inclination adjustment system, called moving mass, is used for aligning the mirror orientation in pitch. Photo-reflective displacement sensors, which have a large range, are installed for damping control on marionette recoil mass and intermediate recoil mass. Samarium cobalt magnets are used for coil-magnet actuators to prevent significant change of magnetism between room temperature and cryogenic temperature. In this paper, the design of our first cryogenic payload and its performance during bKAGRA phase 1 are discussed.
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Journal of Physics: Conference Series, 1857(1) 012002-012002, Apr 1, 2021
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Classical and Quantum Gravity, 38(6) 065011-065011, Mar 18, 2021
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Living Reviews in Relativity, 23(1) 3-3, Dec, 2020<title>Abstract</title>We present our current best estimate of the plausible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next several years, with the intention of providing information to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals for the third (O3), fourth (O4) and fifth observing (O5) runs, including the planned upgrades of the Advanced LIGO and Advanced Virgo detectors. We study the capability of the network to determine the sky location of the source for gravitational-wave signals from the inspiral of binary systems of compact objects, that is binary neutron star, neutron star–black hole, and binary black hole systems. The ability to localize the sources is given as a sky-area probability, luminosity distance, and comoving volume. The median sky localization area (90% credible region) is expected to be a few hundreds of square degrees for all types of binary systems during O3 with the Advanced LIGO and Virgo (HLV) network. The median sky localization area will improve to a few tens of square degrees during O4 with the Advanced LIGO, Virgo, and KAGRA (HLVK) network. During O3, the median localization volume (90% credible region) is expected to be on the order of <inline-formula><alternatives><tex-math>$$10^{5}, 10^{6}, 10^{7}\mathrm {\ Mpc}^3$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msup> <mml:mn>10</mml:mn> <mml:mn>5</mml:mn> </mml:msup> <mml:mo>,</mml:mo> <mml:msup> <mml:mn>10</mml:mn> <mml:mn>6</mml:mn> </mml:msup> <mml:mo>,</mml:mo> <mml:msup> <mml:mn>10</mml:mn> <mml:mn>7</mml:mn> </mml:msup> <mml:msup> <mml:mrow> <mml:mspace /> <mml:mi>Mpc</mml:mi> </mml:mrow> <mml:mn>3</mml:mn> </mml:msup> </mml:mrow> </mml:math></alternatives></inline-formula> for binary neutron star, neutron star–black hole, and binary black hole systems, respectively. The localization volume in O4 is expected to be about a factor two smaller than in O3. We predict a detection count of <inline-formula><alternatives><tex-math>$$1^{+12}_{-1}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mn>1</mml:mn> <mml:mrow> <mml:mo>-</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>12</mml:mn> </mml:mrow> </mml:msubsup> </mml:math></alternatives></inline-formula>(<inline-formula><alternatives><tex-math>$$10^{+52}_{-10}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mn>10</mml:mn> <mml:mrow> <mml:mo>-</mml:mo> <mml:mn>10</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>52</mml:mn> </mml:mrow> </mml:msubsup> </mml:math></alternatives></inline-formula>) for binary neutron star mergers, of <inline-formula><alternatives><tex-math>$$0^{+19}_{-0}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mn>0</mml:mn> <mml:mrow> <mml:mo>-</mml:mo> <mml:mn>0</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>19</mml:mn> </mml:mrow> </mml:msubsup> </mml:math></alternatives></inline-formula>(<inline-formula><alternatives><tex-math>$$1^{+91}_{-1}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mn>1</mml:mn> <mml:mrow> <mml:mo>-</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>91</mml:mn> </mml:mrow> </mml:msubsup> </mml:math></alternatives></inline-formula>) for neutron star–black hole mergers, and <inline-formula><alternatives><tex-math>$$17^{+22}_{-11}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mn>17</mml:mn> <mml:mrow> <mml:mo>-</mml:mo> <mml:mn>11</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>22</mml:mn> </mml:mrow> </mml:msubsup> </mml:math></alternatives></inline-formula>(<inline-formula><alternatives><tex-math>$$79^{+89}_{-44}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mn>79</mml:mn> <mml:mrow> <mml:mo>-</mml:mo> <mml:mn>44</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>89</mml:mn> </mml:mrow> </mml:msubsup> </mml:math></alternatives></inline-formula>) for binary black hole mergers in a one-calendar-year observing run of the HLV network during O3 (HLVK network during O4). We evaluate sensitivity and localization expectations for unmodeled signal searches, including the search for intermediate mass black hole binary mergers.
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Physics Letters, Section A: General, Atomic and Solid State Physics, 384(26), Sep 18, 2020 Peer-reviewed
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Physical Review D, 102(2), Jul 24, 2020 Peer-reviewed
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Progress of Theoretical and Experimental Physics, 2020(5), May 1, 2020
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CLASSICAL AND QUANTUM GRAVITY, 37(3) 035004-035004, Feb, 2020 Peer-reviewedCorresponding author
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Journal of Physics: Conference Series, 1342 012014-012014, Jan, 2020
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PHYSICAL REVIEW A, 101(1), Jan, 2020 Peer-reviewed
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CLASSICAL AND QUANTUM GRAVITY, 36(20), Oct, 2019 Peer-reviewed
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Classical and Quantum Gravity, 36(16) 165008-165008, Aug 22, 2019 Peer-reviewed
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Classical and Quantum Gravity, 36(9) 095015-095015, May 9, 2019 Peer-reviewed
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Nature Astronomy, 3(1) 35-40, Jan, 2019 Peer-reviewed
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PHYSICAL REVIEW D, 97(12), Jun, 2018 Peer-reviewed
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Direct approach for the fluctuation-dissipation theorem under nonequilibrium steady-state conditionsPHYSICAL REVIEW D, 97(10), May, 2018 Peer-reviewed
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15th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Astrophysics, and Relativistic Field Theories, MG 2018, 2018
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PROGRESS OF THEORETICAL AND EXPERIMENTAL PHYSICS, 2018(1), Jan, 2018 Peer-reviewed
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CLASSICAL AND QUANTUM GRAVITY, 34(22), Nov, 2017 Peer-reviewed
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PHYSICS LETTERS A, 380(46) 3871-3875, Dec, 2016 Peer-reviewed
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CLASSICAL AND QUANTUM GRAVITY, 33(14), Jul, 2016 Peer-reviewedLead author
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PHYSICAL REVIEW A, 94(1), Jul, 2016 Peer-reviewedLead author
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PHYSICS LETTERS A, 380(9-10) 983-988, Mar, 2016 Peer-reviewed
Misc.
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arXiv:2305.06579, May 11, 2023
Presentations
2-
Ando-Michimura Group Seminar, Oct 24, 2025 Invited
Research Projects
2-
Grants-in-Aid for Scientific Research, Japan Society for the Promotion of Science, Apr, 2021 - Mar, 2023
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Grants-in-Aid for Scientific Research Grant-in-Aid for JSPS Fellows, Japan Society for the Promotion of Science, Apr, 2017 - Mar, 2020
