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arXiv · 2311.11840

An implementation of nDGP gravity in Pinocchio

Yanling Song·Bin Hu·Chengzong Ruan·Chiara Moretti·Pierluigi Monaco
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Abstract

In this paper we investigate dark matter structure formation in the normal branch of the Dvali-Gabadadze-Porrati (nDGP) model using the PINOCCHIO algorithm. We first present 2nd order Lagrangian perturbation theory for the nDGP model, which shows that the 1st- and 2nd-order growth functions in nDGP are larger than those in {\Lambda}CDM. We then examine the dynamics of ellipsoidal collapse in nDGP, which is accelerated compared to {\Lambda}CDM due to enhanced gravitational interactions. Running the nDGP-PINOCCHIO code with a box size of 512 Mpc/h and 1024*1024*1024 particles, we analyze the statistical properties of the output halo catalogs, including the halo power spectrum and halo mass function. The calibrated PINOCCHIO halo power spectrum agrees with N-body simulations within 5% in the comoving wavenumber range k < 0.3 (h/Mpc) at redshift z = 0. The agreement is extended to smaller scales for higher redshifts. For the cumulative halo mass function, the agreement between N-body and PINOCCHIO is also within the simulation scatter.

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Yanling Song, Bin Hu, Chengzong Ruan, Chiara Moretti, Pierluigi Monaco. 2023-11-20. An implementation of nDGP gravity in Pinocchio. https://doi.org/10.1088/1475-7516%2F2024%2F07%2F093

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