We present results from the first high-resolution hydrodynamical simulations of non-Gaussian cosmological models. We focus on the statistical properties of the transmitted Lyman-alpha flux in the high-redshift intergalactic medium. Imprints of non-Gaussianity are present and are larger at high redshifts. Differences larger than 20 per cent at z > 3 in the flux probability distribution function for high-transmissivity regions (voids) are expected for values of the non-linearity parameter f(NL) = +/- 100 when compared to a standard Lambda cold dark matter cosmology with f(NL) = 0. We also investigate the one-dimensional flux bispectrum: at the largest scales (corresponding to tens of Mpc), we expect deviations in the flux bispectrum up to 20 per cent at z similar to 4 (for f(NL) = +/- 100), significantly larger than deviations of similar to 3 per cent in the flux power spectrum. We briefly discuss possible systematic errors that can contaminate the signal. Although challenging, a detection of non-Gaussianities in the interesting regime of scales and redshifts probed by the Lyman-alpha forest could be possible with future data sets.

Viel, M., Branchini, E.F., Dolag, K., Grossi, M., Matarrese, S., Moscardini, L. (2009). Primordial non-Gaussianities in the intergalactic medium. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 393(3), 774-782 [10.1111/j.1365-2966.2008.14236.x].

Primordial non-Gaussianities in the intergalactic medium

BRANCHINI, ENZO FRANCO;
2009-01-01

Abstract

We present results from the first high-resolution hydrodynamical simulations of non-Gaussian cosmological models. We focus on the statistical properties of the transmitted Lyman-alpha flux in the high-redshift intergalactic medium. Imprints of non-Gaussianity are present and are larger at high redshifts. Differences larger than 20 per cent at z > 3 in the flux probability distribution function for high-transmissivity regions (voids) are expected for values of the non-linearity parameter f(NL) = +/- 100 when compared to a standard Lambda cold dark matter cosmology with f(NL) = 0. We also investigate the one-dimensional flux bispectrum: at the largest scales (corresponding to tens of Mpc), we expect deviations in the flux bispectrum up to 20 per cent at z similar to 4 (for f(NL) = +/- 100), significantly larger than deviations of similar to 3 per cent in the flux power spectrum. We briefly discuss possible systematic errors that can contaminate the signal. Although challenging, a detection of non-Gaussianities in the interesting regime of scales and redshifts probed by the Lyman-alpha forest could be possible with future data sets.
2009
Viel, M., Branchini, E.F., Dolag, K., Grossi, M., Matarrese, S., Moscardini, L. (2009). Primordial non-Gaussianities in the intergalactic medium. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 393(3), 774-782 [10.1111/j.1365-2966.2008.14236.x].
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11590/125054
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