The f ( R ) halo mass function in the cosmic web
Abstract
An important indicator of modified gravity is the effect of the local environment on halo properties. This paper examines the influence of the local tidal structure on the halo mass function, the halo orientation, spin and the concentrationmass relation. We use the excursion set formalism to produce a halo mass function conditional on largescale structure. Our simple model agrees well with simulations on large scales at which the density field is linear or weakly nonlinear. Beyond this, our principal result is that f ( R ) does affect halo abundances, the halo spin parameter and the concentrationmass relationship in an environmentindependent way, whereas we find no appreciable deviation from \text(ΛCDM) for the mass function with fixed environment density, nor the alignment of the orientation and spin vectors of the halo to the eigenvectors of the local cosmic web. There is a general trend for greater deviation from \text(ΛCDM) in underdense environments and for highmass haloes, as expected from chameleon screening.
 Authors:
 Astrophysics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom)
 Publication Date:
 OSTI Identifier:
 22679996
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 03; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; ALIGNMENT; CONCENTRATION RATIO; COSMOLOGICAL MODELS; DENSITY; EIGENVECTORS; EXCURSIONS; GRAVITATION; MASS; NONLINEAR PROBLEMS; SIMULATION; SPIN
Citation Formats
BraunBates, F. von, Winther, H.A., Alonso, D., and Devriendt, J., Email: francesca.vonbraunbates@physics.ox.ac.uk, Email: hans.a.winther@physics.ox.ac.uk, Email: david.alonso@physics.ox.ac.uk, Email: julien.devriendt@physics.ox.ac.uk. The f ( R ) halo mass function in the cosmic web. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/03/012.
BraunBates, F. von, Winther, H.A., Alonso, D., & Devriendt, J., Email: francesca.vonbraunbates@physics.ox.ac.uk, Email: hans.a.winther@physics.ox.ac.uk, Email: david.alonso@physics.ox.ac.uk, Email: julien.devriendt@physics.ox.ac.uk. The f ( R ) halo mass function in the cosmic web. United States. doi:10.1088/14757516/2017/03/012.
BraunBates, F. von, Winther, H.A., Alonso, D., and Devriendt, J., Email: francesca.vonbraunbates@physics.ox.ac.uk, Email: hans.a.winther@physics.ox.ac.uk, Email: david.alonso@physics.ox.ac.uk, Email: julien.devriendt@physics.ox.ac.uk. Wed .
"The f ( R ) halo mass function in the cosmic web". United States.
doi:10.1088/14757516/2017/03/012.
@article{osti_22679996,
title = {The f ( R ) halo mass function in the cosmic web},
author = {BraunBates, F. von and Winther, H.A. and Alonso, D. and Devriendt, J., Email: francesca.vonbraunbates@physics.ox.ac.uk, Email: hans.a.winther@physics.ox.ac.uk, Email: david.alonso@physics.ox.ac.uk, Email: julien.devriendt@physics.ox.ac.uk},
abstractNote = {An important indicator of modified gravity is the effect of the local environment on halo properties. This paper examines the influence of the local tidal structure on the halo mass function, the halo orientation, spin and the concentrationmass relation. We use the excursion set formalism to produce a halo mass function conditional on largescale structure. Our simple model agrees well with simulations on large scales at which the density field is linear or weakly nonlinear. Beyond this, our principal result is that f ( R ) does affect halo abundances, the halo spin parameter and the concentrationmass relationship in an environmentindependent way, whereas we find no appreciable deviation from \text(ΛCDM) for the mass function with fixed environment density, nor the alignment of the orientation and spin vectors of the halo to the eigenvectors of the local cosmic web. There is a general trend for greater deviation from \text(ΛCDM) in underdense environments and for highmass haloes, as expected from chameleon screening.},
doi = {10.1088/14757516/2017/03/012},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 03,
volume = 2017,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2017},
month = {Wed Mar 01 00:00:00 EST 2017}
}

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