QUBIC II: Spectro-Polarimetry with Bolometric Interferometry

Abstract

Bolometric interferometry is a novel technique that has the ability to perform spectral imaging. A bolometric interferometer observes the sky in a wide frequency band and can reconstruct sky maps in several sub-bands within the physical band in post-processing of the data. This provides a powerful spectral method to discriminate between the cosmic microwave background (CMB) and astrophysical foregrounds. In this paper, the methodology is illustrated with examples based on the Q \& U Bolometric Interferometer for Cosmology (QUBIC) which is a ground-based instrument designed to measure the B-mode polarization of the sky at millimeter wavelengths. We consider the specific cases of point source reconstruction and Galactic dust mapping and we characterize the point spread function as a function of frequency. We study the noise properties of spectral imaging, especially the correlations between sub-bands, using end-to-end simulations together with a fast noise simulator. We conclude showing that spectral imaging performance are nearly optimal up to five sub-bands in the case of QUBIC.

27 pages, 18 figures. Accepted by JCAP on July 6, 2021. Second paper of series of 8 in a special JCAP edition on QUBIC

References in corpus (15)

• The Atacama Cosmology Telescope: DR4 Maps and Cosmological Parameters
• CMB-S4 Science Case, Reference Design, and Project Plan
• The Atacama Cosmology Telescope: A Measurement of the Cosmic Microwave Background Power Spectra at 98 and 150 GHz
• Spatial variations in the spectral index of polarized synchrotron emission in the 9 yr WMAP sky maps
• QUBIC I: Overview and ScienceProgram
• Detection of Galactic and Extragalactic Millimeter-Wavelength Transient Sources with SPT-3G
• Determining thermal dust emission from Planck HFI data using a sparse, parametric technique
• QUBIC IV: Performance of TES Bolometers and Readout Electronics
• Design and performance of the first BICEP Array receiver
• QUBIC VIII: Optical design and performance
• QUBIC V: Cryogenic system design and performance
• QUBIC III: Laboratory Characterization
• QUBIC VI: cryogenic half wave plate rotator, design and performances
• Anti-reflection Coated Vacuum Window for the Primordial Inflation Polarization ExploreR (PIPER) balloon-borne instrument
• Broadband Fizeau Interferometers for Astrophysics

Cited by in corpus (9)

• QUBIC I: Overview and ScienceProgram
• QUBIC V: Cryogenic system design and performance
• QUBIC VIII: Optical design and performance
• QUBIC III: Laboratory Characterization
• QUBIC VI: cryogenic half wave plate rotator, design and performances
• Enhancing CMB map reconstruction and power spectrum estimation with convolutional neural networks
• QUBIC VII: The feedhorn-switch system of the technological demonstrator
• Bias in the tensor-to-scalar ratio from self-interacting dark radiation
• Optimal method for reconstructing polychromatic maps from broadband observations with an asymmetric antenna pattern