LiteBIRD science goals and forecasts: improving sensitivity to inflationary gravitational waves with multitracer delensing

Namikawa, T.; Lonappan, A. I.; Baccigalupi, C.; Bartolo, N.; Beck, D.; Benabed, K.; Challinor, A.; Diego-Palazuelos, P.; Errard, J.; Farrens, S.; Gruppuso, A.; Krachmalnicoff, N.; Migliaccio, M.; Martínez-González, E.; Pettorino, V.; Piccirilli, G.; Ruiz-Granda, M.; Sherwin, B.; Starck, J.; Vielva, P.; Akizawa, R.; Anand, A.; Aumont, J.; Aurlien, R.; Azzoni, S.; Ballardini, M.; Banday, A. J.; Barreiro, R. B.; Bersanelli, M.; Blinov, D.; Bortolami, M.; Brinckmann, T.; Calabrese, E.; Campeti, P.; Carones, A.; Carralot, F.; Casas, F. J.; Cheung, K.; Clermont, L.; Columbro, F.; Conenna, G.; Coppolecchia, A.; Cuttaia, F.; D'Alessandro, G.; de Bernardis, P.; de Haan, T.; De Petris, M.; Della Torre, S.; Di Giorgi, E.; Eriksen, H. K.; Finelli, F.; Franceschet, C.; Fuskeland, U.; Galloni, G.; Galloway, M.; Georges, M.; Gerbino, M.; Gervasi, M.; Ghigna, T.; Giardiello, S.; Gimeno-Amo, C.; Gjerløw, E.; Hazumi, M.; Henrot-Versillé, S.; Hergt, L. T.; Hivon, E.; Kohri, K.; Komatsu, E.; Lamagna, L.; Lattanzi, M.; Leloup, C.; Lembo, M.; López-Caniego, M.; Luzzi, G.; Maffei, B.; Masi, S.; Massa, M.; Matarrese, S.; Matsumura, T.; Micheli, S.; Moggi, A.; Monelli, M.; Montier, L.; Morgante, G.; Mot, B.; Mousset, L.; Nagata, R.; Natoli, P.; Novelli, A.; Obata, I.; Occhiuzzi, A.; Pagano, L.; Paiella, A.; Paoletti, D.; Pascual-Cisneros, G.; Pavlidou, V.; Piacentini, F.; Pinchera, M.; Pisano, G.; Polenta, G. et al.
Bibliographical reference

Journal of Cosmology and Astroparticle Physics

Advertised on:
6
2024
Number of authors
123
IAC number of authors
1
Citations
13
Refereed citations
7
Description
We estimate the efficiency of mitigating the lensing B-mode polarization, the so-called delensing, for the LiteBIRD experiment with multiple external data sets of lensing-mass tracers. The current best bound on the tensor-to-scalar ratio, r, is limited by lensing rather than Galactic foregrounds. Delensing will be a critical step to improve sensitivity to r as measurements of r become more and more limited by lensing. In this paper, we extend the analysis of the recent LiteBIRD forecast paper to include multiple mass tracers, i.e., the CMB lensing maps from LiteBIRD and CMB-S4-like experiment, cosmic infrared background, and galaxy number density from Euclid- and LSST-like survey. We find that multi-tracer delensing will further improve the constraint on r by about 20%. In LiteBIRD, the residual Galactic foregrounds also significantly contribute to uncertainties of the B-modes, and delensing becomes more important if the residual foregrounds are further reduced by an improved component separation method.
Related projects
Full-sky map showing the spatial distribution of the primary anisotropies of the Cosmic Microwave Background (generated 380,000 years after the Big Bang) derived from observations of the Planck satellite
Anisotropy of the Cosmic Microwave Background
The general goal of this project is to determine and characterize the spatial and spectral variations in the temperature and polarisation of the Cosmic Microwave Background in angular scales from several arcminutes to several degrees. The primordial matter density fluctuations which originated the structure in the matter distribution of the present
Rafael
Rebolo López