Spectral Imaging with QUBIC: building frequency maps from Time-Ordered-Data using Bolometric Interferometry
Year: 2024
Type: preprint
Abstract: The search for relics from the inflation era in the form of B-mode polarization of the CMB is a major challenge in cosmology. The main obstacle appears to come from the complexity of Galactic foregrounds that need to be removed. Multi-frequency observations are key to mitigating their contamination and mapping primordial fluctuations. We present spectral-imaging, a method to reconstruct sub-frequency maps of the CMB polarization within the instrument's physical bandwidth, a unique feature of Bolometric Interferometry that could be crucial for foreground mitigation as it provides an increased spectral resolution. Our technique uses the frequency evolution of the shape of the Bolometric Interferometer's synthesized beam to reconstruct frequency information from the time domain data. We reconstruct sub-frequency maps using an inverse problem approach based on detailed modeling of the instrument acquisition. We use external data to regularize the convergence of the estimator and account for bandpass mismatch and varying angular resolution. The reconstructed maps are unbiased and allow exploiting the spectral-imaging capacity of QUBIC. Using end-to-end simulations of the QUBIC instrument, we perform a cross-spectra analysis to extract a forecast on the tensor-to-scalar ratio constraint of $σ(r)= 0.0225$ after component separation.
Source: arXiv (Cornell University)
Authors: Regnier, M., Laclavère, T., Hamilton, J-Ch., Bunn, E., Chabirand, V., Chanial, P., Goetz, L., Kardum, L., Huchet, A., Masson, P., Granese, N. Miron, Scóccola, C. G., Torchinsky, S. A., Battistelli, E., Bersanelli, M., Columbro, F., Coppolecchia, A., Costanza, B., De Bernardis, P., De Gasperis, G., Ferazzoli, S., Flood, A., Ganga, K., Gervasi, M., Grandsire, L., Manzan, E ., Masi, S., Mennella, A., Mousset, L., O'Sullivan, C., Paiella, A., Piacentini, F., Piat, M., Piccirillo, L., Rasztocky, E., Stolpovskiy, M., Zannoni, M.
Institutions: Centre National de la Recherche Scientifique, Université Paris Cité, Université Paris Diderot, University of Richmond, École Polytechnique, Institut Polytechnique de Paris, École Normale Supérieure - PSL, Laboratoire de Physique de l'Ecole Normale Supérieure, Universidad Nacional de La Plata, Université Paris Sciences et Lettres, Observatoire de Paris, Istituto Nazionale di Fisica Nucleare, Sezione di Roma I, Sapienza University of Rome, University of Milan, Istituto Nazionale di Fisica Nucleare, Sezione di Milano, National University of Ireland, Maynooth, Istituto Nazionale di Fisica Nucleare, Istituto Nazionale di Fisica Nucleare, Sezione di Milano Bicocca, University of Milano-Bicocca, Sorbonne Université, École Normale Supérieure, University of Manchester, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto Argentino de Radioastronomía, University of Bern, International Space Science Institute
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: Agence Nationale de la Recherche, Comisión Nacional de Energía Atómica, Gobierno de Argentina, Consejo Nacional de Investigaciones Científicas y Técnicas, Ministerio de Ciencia, Tecnología e Innovación Productiva, Consiglio Nazionale delle Ricerche, Centre National de la Recherche Scientifique, Istituto Nazionale di Fisica Nucleare, Institut National de Physique Nucléaire et de Physique des Particules
OpenAlex ID: W4403241404