Cluster abundance in chameleon f ( R ) gravity I: toward an accurate halo mass function prediction

Journal Article · Thu Dec 01 04:00:00 EST 2016 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2016/12/024· OSTI ID:22679361

Cataneo, Matteo; Rapetti, David ^[1]; Lombriser, Lucas ^[2]; Li, Baojiu ^[3]

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1. Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen (Denmark)
2. Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ (United Kingdom)
3. Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom)

We refine the mass and environment dependent spherical collapse model of chameleon f ( R ) gravity by calibrating a phenomenological correction inspired by the parameterized post-Friedmann framework against high-resolution N -body simulations. We employ our method to predict the corresponding modified halo mass function, and provide fitting formulas to calculate the enhancement of the f ( R ) halo abundance with respect to that of General Relativity (GR) within a precision of ∼< 5% from the results obtained in the simulations. Similar accuracy can be achieved for the full f ( R ) mass function on the condition that the modeling of the reference GR abundance of halos is accurate at the percent level. We use our fits to forecast constraints on the additional scalar degree of freedom of the theory, finding that upper bounds competitive with current Solar System tests are within reach of cluster number count analyses from ongoing and upcoming surveys at much larger scales. Importantly, the flexibility of our method allows also for this to be applied to other scalar-tensor theories characterized by a mass and environment dependent spherical collapse.

• OSTI ID: 22679361
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 12 Vol. 2016; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ABUNDANCE
ACCURACY
CORRECTIONS
DEGREES OF FREEDOM
FLEXIBILITY
FORECASTING
GENERAL RELATIVITY THEORY
GRAVITATION
MASS
QUANTUM GRAVITY
RESOLUTION
SIMULATION
SOLAR SYSTEM
SPHERICAL CONFIGURATION