2026-04-13T04:27:29Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1317612025-12-05T16:11:46Zcom_2072_1057col_2072_478904col_2072_478917

00925njm 22002777a 4500 dc Mangilli, Anna author Verde, Licia author 2019-04-08T11:02:21Z 2019-04-08T11:02:21Z 2009-12-08 2019-04-08T11:02:21Z We revisit the predictions for the expected cosmic microwave background bispectrum signal from the cross-correlation of the primary-lensing-Rees-Sciama signal; we point out that it can be a significant contaminant to the bispectrum signal from primordial non-Gaussianity of the local type. This non-Gaussianity, usually parametrized by the non-Gaussian parameter f N L , arises, for example, in multifield inflation. In particular both signals are frequency-independent, and are maximized for nearly squeezed configurations. While their detailed scale-dependence and harmonic imprints are different for generic bispectrum shapes, we show that, if not included in the modeling, the primary-lensing-Rees-Sciama contribution yields an effective f N L of 10 when using a bispectrum estimator optimized for local non-Gaussianity. Considering that expected 1 − σ errors on f N L are < 10 from forthcoming experiments, we conclude that the contribution from this signal must be included in future constraints on f N L from the cosmic microwave background bispectrum. Física de partícules Experiments Ones de gravetat Particle physics Experiments Gravity waves Non-Gaussianity and the CMB bispectrum: Confusion between primordial and lensing-Rees-Sciama contribution?