ORCID Profile
0000-0002-3266-857X
Current Organisations
University of Tokyo
,
Kavli IPMU, University of Tokyo
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Publisher: SPIE
Date: 16-12-2020
DOI: 10.1117/12.2561841
Publisher: IOP Publishing
Date: 2022
DOI: 10.1088/1475-7516/2022/01/039
Abstract: We present a demonstration of the in-flight polarization angle calibration for the JAXA/ISAS second strategic large class mission, LiteBIRD , and estimate its impact on the measurement of the tensor-to-scalar ratio parameter, r , using simulated data. We generate a set of simulated sky maps with CMB and polarized foreground emission, and inject instrumental noise and polarization angle offsets to the 22 (partially overlapping) LiteBIRD frequency channels. Our in-flight angle calibration relies on nulling the EB cross correlation of the polarized signal in each channel. This calibration step has been carried out by two independent groups with a blind analysis, allowing an accuracy of the order of a few arc-minutes to be reached on the estimate of the angle offsets. Both the corrected and uncorrected multi-frequency maps are propagated through the foreground cleaning step, with the goal of computing clean CMB maps. We employ two component separation algorithms, the Bayesian-Separation of Components and Residuals Estimate Tool ( B-SeCRET ), and the Needlet Internal Linear Combination ( NILC ). We find that the recovered CMB maps obtained with algorithms that do not make any assumptions about the foreground properties, such as NILC , are only mildly affected by the angle miscalibration. However, polarization angle offsets strongly bias results obtained with the parametric fitting method. Once the miscalibration angles are corrected by EB nulling prior to the component separation, both component separation algorithms result in an unbiased estimation of the r parameter. While this work is motivated by the conceptual design study for LiteBIRD , its framework can be broadly applied to any CMB polarization experiment. In particular, the combination of simulation plus blind analysis provides a robust forecast by taking into account not only detector sensitivity but also systematic effects.
Publisher: American Astronomical Society
Date: 20-11-2020
Publisher: SPIE
Date: 19-08-2014
DOI: 10.1117/12.2057332
Publisher: SPIE
Date: 19-08-2014
DOI: 10.1117/12.2055572
Publisher: American Astronomical Society
Date: 07-2020
Publisher: American Physical Society (APS)
Date: 02-04-2014
Publisher: American Physical Society (APS)
Date: 08-12-2015
Publisher: Springer Science and Business Media LLC
Date: 05-09-2022
Publisher: American Physical Society (APS)
Date: 04-2020
Publisher: SPIE
Date: 15-12-2020
DOI: 10.1117/12.2562243
Publisher: Springer Science and Business Media LLC
Date: 06-01-2016
Publisher: SPIE
Date: 21-12-2020
DOI: 10.1117/12.2563050
Publisher: American Physical Society (APS)
Date: 18-08-2023
Publisher: American Astronomical Society
Date: 17-04-2020
Publisher: American Astronomical Society
Date: 11-08-2015
Publisher: American Astronomical Society
Date: 27-05-2022
Abstract: We report an improved measurement of the degree-scale cosmic microwave background B -mode angular-power spectrum over 670 deg 2 sky area at 150 GHz with P olarbear . In the original analysis of the data, errors in the angle measurement of the continuously rotating half-wave plate, a polarization modulator, caused significant data loss. By introducing an angle-correction algorithm, the data volume is increased by a factor of 1.8. We report a new analysis using the larger data set. We find the measured B -mode spectrum is consistent with the ΛCDM model with Galactic dust foregrounds. We estimate the contamination of the foreground by cross-correlating our data and Planck 143, 217, and 353 GHz measurements, where its spectrum is modeled as a power law in angular scale and a modified blackbody in frequency. We place an upper limit on the tensor-to-scalar ratio r 0.33 at 95% confidence level after marginalizing over the foreground parameters.
Publisher: American Astronomical Society
Date: 13-10-2017
Publisher: Springer Science and Business Media LLC
Date: 07-09-2018
Publisher: Springer Science and Business Media LLC
Date: 27-01-2020
DOI: 10.1007/S10909-019-02329-W
Abstract: Recent developments of transition-edge sensors (TESs), based on extensive experience in ground-based experiments, have been making the sensor techniques mature enough for their application on future satellite cosmic microwave background (CMB) polarization experiments. LiteBIRD is in the most advanced phase among such future satellites, targeting its launch in Japanese Fiscal Year 2027 (2027FY) with JAXA’s H3 rocket. It will accommodate more than 4000 TESs in focal planes of reflective low-frequency and refractive medium-and-high-frequency telescopes in order to detect a signature imprinted on the CMB by the primordial gravitational waves predicted in cosmic inflation. The total wide frequency coverage between 34 and 448 GHz enables us to extract such weak spiral polarization patterns through the precise subtraction of our Galaxy’s foreground emission by using spectral differences among CMB and foreground signals. Telescopes are cooled down to 5 K for suppressing thermal noise and contain polarization modulators with transmissive half-wave plates at in idual apertures for separating sky polarization signals from artificial polarization and for mitigating from instrumental 1/ f noise. Passive cooling by using V-grooves supports active cooling with mechanical coolers as well as adiabatic demagnetization refrigerators. Sky observations from the second Sun–Earth Lagrangian point, L2, are planned for 3 years. An international collaboration between Japan, the USA, Canada, and Europe is sharing various roles. In May 2019, the Institute of Space and Astronautical Science, JAXA, selected LiteBIRD as the strategic large mission No. 2.
Publisher: American Astronomical Society
Date: 18-11-2019
Publisher: American Physical Society (APS)
Date: 09-07-2014
Publisher: American Astronomical Society
Date: 23-10-2017
Publisher: SPIE
Date: 23-07-2014
DOI: 10.1117/12.2055611
Publisher: American Astronomical Society
Date: 04-09-2019
Publisher: American Astronomical Society
Date: 14-01-2019
Publisher: AIP Publishing
Date: 2021
DOI: 10.1063/5.0038197
Location: United States of America
Location: United States of America
No related grants have been discovered for Yuji Chinone.