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arXiv · 1905.05697

Planck 2018 results. IX. Constraints on primordial non-Gaussianity

Planck Collaboration·Y. Akrami·F. Arroja·M. Ashdown·J. Aumont·C. Baccigalupi·M. Ballardini·A. J. Banday·R. B. Barreiro·N. Bartolo·S. Basak·K. Benabed·J. -P. Bernard·M. Bersanelli·P. Bielewicz·J. R. Bond·J. Borrill·F. R. Bouchet·M. Bucher·C. Burigana·R. C. Butler·E. Calabrese·J. -F. Cardoso·B. Casaponsa·A. Challinor·H. C. Chiang·L. P. L. Colombo·C. Combet·B. P. Crill·F. Cuttaia·P. de Bernardis·A. de Rosa·G. de Zotti·J. Delabrouille·J. -M. Delouis·E. Di Valentino·J. M. Diego·O. Doré·M. Douspis·A. Ducout·X. Dupac·S. Dusini·G. Efstathiou·F. Elsner·T. A. Enßlin·H. K. Eriksen·Y. Fantaye·J. Fergusson·R. Fernandez-Cobos·F. Finelli·M. Frailis·A. A. Fraisse·E. Franceschi·A. Frolov·S. Galeotta·K. Ganga·R. T. Génova-Santos·M. Gerbino·J. González-Nuevo·K. M. Górski·S. Gratton·A. Gruppuso·J. E. Gudmundsson·J. Hamann·W. Handley·F. K. Hansen·D. Herranz·E. Hivon·Z. Huang·A. H. Jaffe·W. C. Jones·G. Jung·E. Keihänen·R. Keskitalo·K. Kiiveri·J. Kim·N. Krachmalnicoff·M. Kunz·H. Kurki-Suonio·J. -M. Lamarre·A. Lasenby·M. Lattanzi·C. R. Lawrence·M. Le Jeune·F. Levrier·A. Lewis·M. Liguori·P. B. Lilje·V. Lindholm·M. López-Caniego·Y. -Z. Ma·J. F. Macías-Pérez·G. Maggio·D. Maino·N. Mandolesi·A. Marcos-Caballero·M. Maris·P. G. Martin·E. Martínez-González·S. Matarrese
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Abstract

We analyse the Planck full-mission cosmic microwave background (CMB) temperature and E-mode polarization maps to obtain constraints on primordial non-Gaussianity (NG). We compare estimates obtained from separable template-fitting, binned, and modal bispectrum estimators, finding consistent values for the local, equilateral, and orthogonal bispectrum amplitudes. Our combined temperature and polarization analysis produces the following results: f_NL^local = -0.9 +\- 5.1; f_NL^equil = -26 +\- 47; and f_NL^ortho = - 38 +\- 24 (68%CL, statistical). These results include the low-multipole (4 <= l < 40) polarization data, not included in our previous analysis, pass an extensive battery of tests, and are stable with respect to our 2015 measurements. Polarization bispectra display a significant improvement in robustness; they can now be used independently to set NG constraints. We consider a large number of additional cases, e.g. scale-dependent feature and resonance bispectra, isocurvature primordial NG, and parity-breaking models, where we also place tight constraints but do not detect any signal. The non-primordial lensing bispectrum is detected with an improved significance compared to 2015, excluding the null hypothesis at 3.5 sigma. We present model-independent reconstructions and analyses of the CMB bispectrum. Our final constraint on the local trispectrum shape is g_NLl^local = (-5.8 +\-6.5) x 10^4 (68%CL, statistical), while constraints for other trispectra are also determined. We constrain the parameter space of different early-Universe scenarios, including general single-field models of inflation, multi-field and axion field parity-breaking models. Our results provide a high-precision test for structure-formation scenarios, in complete agreement with the basic picture of the LambdaCDM cosmology regarding the statistics of the initial conditions (abridged).

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Planck Collaboration, Y. Akrami, F. Arroja, M. Ashdown, J. Aumont, C. Baccigalupi, M. Ballardini, A. J. Banday, R. B. Barreiro, N. Bartolo, S. Basak, K. Benabed, J. -P. Bernard, M. Bersanelli, P. Bielewicz, J. R. Bond, J. Borrill, F. R. Bouchet, M. Bucher, C. Burigana, R. C. Butler, E. Calabrese, J. -F. Cardoso, B. Casaponsa, A. Challinor, H. C. Chiang, L. P. L. Colombo, C. Combet, B. P. Crill, F. Cuttaia, P. de Bernardis, A. de Rosa, G. de Zotti, J. Delabrouille, J. -M. Delouis, E. Di Valentino, J. M. Diego, O. Doré, M. Douspis, A. Ducout, X. Dupac, S. Dusini, G. Efstathiou, F. Elsner, T. A. Enßlin, H. K. Eriksen, Y. Fantaye, J. Fergusson, R. Fernandez-Cobos, F. Finelli, M. Frailis, A. A. Fraisse, E. Franceschi, A. Frolov, S. Galeotta, K. Ganga, R. T. Génova-Santos, M. Gerbino, J. González-Nuevo, K. M. Górski, S. Gratton, A. Gruppuso, J. E. Gudmundsson, J. Hamann, W. Handley, F. K. Hansen, D. Herranz, E. Hivon, Z. Huang, A. H. Jaffe, W. C. Jones, G. Jung, E. Keihänen, R. Keskitalo, K. Kiiveri, J. Kim, N. Krachmalnicoff, M. Kunz, H. Kurki-Suonio, J. -M. Lamarre, A. Lasenby, M. Lattanzi, C. R. Lawrence, M. Le Jeune, F. Levrier, A. Lewis, M. Liguori, P. B. Lilje, V. Lindholm, M. López-Caniego, Y. -Z. Ma, J. F. Macías-Pérez, G. Maggio, D. Maino, N. Mandolesi, A. Marcos-Caballero, M. Maris, P. G. Martin, E. Martínez-González, S. Matarrese. 2019-05-14. Planck 2018 results. IX. Constraints on primordial non-Gaussianity. https://arxiv.org/abs/1905.05697

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