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Webmaster：Ippei Obata
Affiliation：Kavli IPMU, University of Tokyo
Research Interest：Axion cosmology
Research Activities：Publication List
E-mail：ippei.obata_at_ipmu.jp（_at_→@）
News
2024.3.6 Submitted a collaboration paper
A.G. Abac et al. (LVK Collaborations),
"Ultralight vector dark matter search using data from the KAGRA O3GK run"
https://arxiv.org/abs/2403.03004
2023.12.21 Submitted a paper
R.Z. Ferreira, S. Gasparotto, T. Hiramatsu, I. Obata, O. Pujolas,
"Axionic defects in the CMB: birefringence and gravitational waves"
https://arxiv.org/abs/2312.14104
2023.12.14 Submitted a collaboration paper
C. Leloup et al. (LiteBIRD Collaboration)
"Impact of beam far side-lobe knowledge in the presence of foregrounds for LiteBIRD"
https://arxiv.org/abs/2312.09001
2023.12.8 Submitted a collaboration paper
A.I. Lonappan et al. (LiteBIRD Collaboration)
"LiteBIRD Science Goals and Forecasts: A full-sky measurement of gravitational lensing of the CMB"
https://arxiv.org/abs/2312.05184
2023.12.8 Submitted a collaboration paper
T. Namikawa et al. (LiteBIRD Collaboration)
"LiteBIRD Science Goals and Forecasts: Improving Sensitivity to Inflationary Gravitational Waves with Multitracer Delensing"
https://arxiv.org/abs/2312.05194
2023.12.1 Submitted a collaboration paper
P. Campeti et al. (LiteBIRD Collaboration)
"LiteBIRD Science Goals and Forecasts. A Case Study of the Origin of Primordial Gravitational Waves using Large-Scale CMB Polarization"
https://arxiv.org/abs/2312.00717
2023.11.27 The paper
"Stochastic effects on observation of ultralight bosonic dark matter"
is published in PRD: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.108.092010
2023.10.13 Submitted a paper
Y. Nakai, R. Namba, I. Obata, Y-C. Qiu, R. Saito,
"Can we explain cosmic birefringence without a new light field beyond Standard Model?"
https://arxiv.org/abs/2310.09152
2023.10.10 The paper
"First results of axion dark matter search with DANCE"
is published in PRD: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.108.072005
2023.10.9 The paper
"Cosmic birefringence tomography with polarized Sunyaev-Zel'dvich effect"
is published in PRD: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.108.083510
2023.10.5 Submitted a paper
T. Fujita, T. Murata, I. Obata, M. Shiraishi,
"Parity-violating scalar trispectrum from a rolling axion during inflation"
https://arxiv.org/abs/2310.03551
2023.8.15 The paper
"Peaky Production of Light Dark Photon Dark Matter"
is published in JCAP: https://iopscience.iop.org/article/10.1088/1475-7516/2023/08/032
2023.7.5 Submitted a paper
C. Ünal, A. Papageorgiou, I. Obata,
"Axion-Gauge Dynamics During Inflation as the Origin of Pulsar Timing Array Signals and Primordial Black Holes"
https://arxiv.org/abs/2307.02322
2023.6.15 Submitted a paper
T. Namikawa, I. Obata,
"Cosmic birefringence tomography with polarized Sunyaev Zel'dovich effect"
https://arxiv.org/abs/2306.08875
2023.3.7 Submitted a paper
Y. Oshima et al.
"First Results of Axion Dark Matter Search with DANCE"
https://arxiv.org/abs/2303.03594v2
2022.12.22 Submitted a paper
Y. Nakai, R. Namba, I. Obata,
"Peaky Production of Light Dark Photon Dark Matter"
https://arxiv.org/abs/2212.11516
2022.5.5 Submitted a paper
"Stochastic effects on observation of ultralight bosonic dark matter"
https://arxiv.org/abs/2205.02960
2022.3.17 Submitted a paper
S.Gasparotto, I.Obata,
"Cosmic Birefringence from Monodromic Axion Dark Energy"
https://arxiv.org/abs/2203.09409
2022.3.7 Submitted a paper
P.Campeti, O.Özsoy, I.Obata, M.Shiraishi,
"New constraints on axion-gauge field dynamics during inflation from Planck and BICEP/Keck data sets"
https://arxiv.org/abs/2203.03401
2022.3.3 The paper
"Axion-Gauge Field Dynamics with Backreaction"
is published in JCAP: https://iopscience.iop.org/article/10.1088/1475-7516/2022/03/010
2022.2.8 Submitted a paper
T.Fujita, H.Nakatsuka, I.Obata, S.Young,
"inflation with two-form field: the production of primordial black holes and gravitational waves"
https://arxiv.org/abs/2202.02401
2022.1.4 The paper
T.Fujita, K.Murai, I.Obata, M.Shiraishi,
"Gravitational wave trispectrum in the axion-SU(2) model"
https://arxiv.org/abs/2109.06457
is published in JCAP: https://iopscience.iop.org/article/10.1088/1475-7516/2022/01/007
2021.11.29 Submitted a paper
K. Ishiwata, E.Komatsu, I.Obata,
"Axion-Gauge Field Dynamics with Backreaction"
https://arxiv.org/abs/2111.14429
2021.9.14 Submitted a paper
T.Fujita, K.Murai, I.Obata, M.Shiraishi,
"Gravitational wave trispectrum in the axion-SU(2) model"
https://arxiv.org/abs/2109.06457
2021.8.4 Submitted a paper
I.Obata,
"Implications of the Cosmic Birefringence Measurement for the Axion Dark Matter Search"
https://arxiv.org/abs/2108.02150
2021.6.15 Submitted a paper:
K.Nagano, H.Nakatsuka, S.Morisaki, T.Fujita, Y.Michimura, I.Obata,
"Good Luck lies in odd numbers: axion dark matter search using arm cavity transmitted beam of gravitational wave detectors",
https://arxiv.org/abs/2106.06800
2021.1.11: Talk @MPA Institute seminar "Primordial gravitational waves from inflation with gauge field" [Talk Slide].
2020.11.10: Submitted a paper:
S.Morisaki, T.Fujita, Y.Michimura, H. Nakatsuka, I.Obata,
"Improved sensitivity of interferometric gravitational wave detectors to ultralight vector dark matter from the finite light-traveling time",
2020.10.6: Talk @MPA Cosmology seminar "Axion Dark Matter Search with Optical Interferometers" [Talk Slide].