An accurate halo model for fitting non-linear cosmological power spectra and baryonic feedback models

By A. Mead, J. Peacock, Catherine Heymans, S. Joudaki, Alan Heavens. 2015

289 citations recorded by the source corpus.

We present an optimized variant of the halo model, designed to produce accurate matter power spectra well into the non-linear regime for a wide range of cosmological models. To do this, we introduce physically motivated free parameters into the halo-model formalism and fit these to data from high-resolution $N$-body simulations. For a variety of $\Lambda$CDM and $w$CDM models the halo-model power is accurate to $\simeq 5$ per cent for $k\leq 10h\,\mathrm{Mpc}$ and $z\leq 2$. An advantage of our new halo model is that it can be adapted to account for the effects of baryonic feedback on the power spectrum. We demonstrate this by fitting the halo model to power spectra from the OWLS hydrodynamical simulation suite via parameters that govern halo internal structure. We are able to fit all feedback models investigated at the 5 per cent level using only two free parameters, and we place limits on the range of these halo parameters for feedback models investigated by the OWLS simulations. Accurate predictions to high-$k$ are vital for weak lensing surveys, and these halo parameters could be considered nuisance parameters to marginalize over in future analyses to mitigate uncertainty regarding the details of feedback. Finally, we investigate how lensing observables predicted by our model compare to those from simulations and from HALOFIT for a range of $k$-cuts and feedback models and quantify the angular scales at which these effects become important. Code to calculate power spectra from the model presented in this paper can be found at this https URL

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/fca2617c1587fb17f66b275dcf17791479d2514c

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Citations in the corpus

Accurate halo-model matter power spectra with dark energy, massive neutrinos and modified gravitational forces (2016, methodology): “In Mead et al. (2015b), we demonstrated the absolute accuracy of our augmented halo model and we direct the reader to that paper for more information.”
Quantifying baryon effects on the matter power spectrum and the weak lensing shear correlation (2018, methodology): “[17] who achieved good agreement with the OWLS hydrodynamical runs [18] by adding two parameters to their power spectrum estimator.”
Cosmology from the Chinese Space Station Optical Survey (CSS-OS) (2019, methodology): “The HMcode is used to calculate the non-linear matter power spectrum for the wCDM model (Mead et al. 2015, 2016).”
The Atacama Cosmology Telescope: DR6 Gravitational Lensing Map and Cosmological Parameters (2023, methodology): “We use the mead2016 non-linear matter power spectrum prescription (Mead et al. 2015, 2016), but note that since our measurement mainly probes linear scales, this choice and baryonic feedback effects do not matter at current sensitivities.”
COSMOLIKE - cosmological likelihood analyses for photometric galaxy surveys (2016, methodology): “In Eifler et al. (2015) we have developed a mitigation technique for baryonic effects in cosmic shear that removes corresponding LSST biases effectively even out to l = 5000 (also see Zentner et al. 2013; Mead et al. 2015).”
The first-year shear catalog of the Subaru Hyper Suprime-Cam Subaru Strategic Program Survey (2017, background): “…for the ensemble of galaxies, avoiding certain systematic errors in the process. alignments of galaxy shapes (Joachimi et al. 2015; Kiessling et al. 2015; Kirk et al. 2015; Troxel & Ishak 2015) and the impact of baryonic effects on the matter power spectrum (Zentner et al. 2013; Mead et al. 2015).”
KiDS-450: The tomographic weak lensing power spectrum and constraints on cosmological parameters (2017, methodology): “Hildebrandt et al. (2017) used an alternative description for the baryon feedback model by Mead et al. (2015), which also includes massive neutrinos on non-linear scales.”
Cosmology from cosmic shear power spectra with Subaru Hyper Suprime-Cam first-year data (2018, methodology): “Mead et al. (2015) find that these two parameters are degenerate and related to each other as η0 = 1.03− 0.11cmin among different feedback models.”
CFHTLenS revisited: assessing concordance with Planck including astrophysical systematics (2016, methodology): “As one would expect from Mead et al. (2015), which is in excellent agreement with Takahashi et al. (2012) for cosmologies where no baryonic effects are included, the contours agree remarkably well for this DM-only scenario.”
hmcode-2020: improved modelling of non-linear cosmological power spectra with baryonic feedback (2020, methodology): “This is similar to the approach taken in Mead et al. (2015) and Mead et al. (2020).”
KiDS+VIKING-450 and DES-Y1 combined: Cosmology with cosmic shear (2019, background): “…space by fixing the sum of neutrino masses to 0.06 eV instead of varying it freely, a change in the uniform sampling of As → ln(1010As), and a change from halofit (Takahashi et al. 2012) to hmcode (Mead et al. 2015) for the modeling of the nonlinear corrections to the matter power spectrum.”
KiDS+VIKING-450: Cosmic shear tomography with optical and infrared data (2018, methodology): “Baryon feedback is modelled with HMCode (Mead et al. 2015), which implements a halo model description, using the same dependence of the two parameters B (amplitude of the halo mass-concentration relation) and η0 (halo bloating parameter) as in Joudaki et al. (2018): η0 = 0.98−0.12B.”
KiDS-450: testing extensions to the standard cosmological model (2016, methodology): “For these reasons, we expect HMCODE to be adequate over our full prior range.”