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Title: Astrophysical tests of gravity: a screening map of the nearby universe

Abstract

Astrophysical tests of modified gravity theories in the nearby universe have been emphasized recently by Hui 2009 and Jain 2011. A key element of such tests is the screening mechanism whereby general relativity is restored in massive halos or high density environments like the Milky Way. In chameleon theories of gravity, including all f(R) models, field dwarf galaxies may be unscreened and therefore feel an extra force, as opposed to screened galaxies. The first step to study differences between screened and unscreened galaxies is to create a 3D screening map. We use N-body simulations to test and calibrate simple approximations to determine the level of screening in galaxy catalogs. Sources of systematic errors in the screening map due to observational inaccuracies are modeled and their contamination is estimated. We then apply our methods to create a map out to 200 Mpc in the Sloan Digital Sky Survey footprint using data from the Sloan survey and other sources. In two companion papers this map will be used to carry out new tests of gravity using distance indicators and the disks of dwarf galaxies. We also make our screening map publicly available.

Authors:
; ;  [1]; ;  [2]
  1. Center for Particle Cosmology, Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104-6396 (United States)
  2. Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Burnaby Road, Portsmouth, PO1 3FX (United Kingdom)
Publication Date:
OSTI Identifier:
22280043
Resource Type:
Journal Article
Journal Name:
Journal of Cosmology and Astroparticle Physics
Additional Journal Information:
Journal Volume: 2012; Journal Issue: 07; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1475-7516
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; APPROXIMATIONS; ASTROPHYSICS; COMPUTERIZED SIMULATION; COSMOLOGY; DENSITY; GENERAL RELATIVITY THEORY; GRAVITATION; MILKY WAY; UNIVERSE

Citation Formats

Cabré, Anna, Vikram, Vinu, Jain, Bhuvnesh, Zhao, Gong-Bo, and Koyama, Kazuya, E-mail: annanusca@gmail.com, E-mail: vinu@sas.upenn.edu, E-mail: gong-bo.zhao@port.ac.uk, E-mail: bjain@physics.upenn.edu, E-mail: Kazuya.Koyama@port.ac.uk. Astrophysical tests of gravity: a screening map of the nearby universe. United States: N. p., 2012. Web. doi:10.1088/1475-7516/2012/07/034.
Cabré, Anna, Vikram, Vinu, Jain, Bhuvnesh, Zhao, Gong-Bo, & Koyama, Kazuya, E-mail: annanusca@gmail.com, E-mail: vinu@sas.upenn.edu, E-mail: gong-bo.zhao@port.ac.uk, E-mail: bjain@physics.upenn.edu, E-mail: Kazuya.Koyama@port.ac.uk. Astrophysical tests of gravity: a screening map of the nearby universe. United States. doi:10.1088/1475-7516/2012/07/034.
Cabré, Anna, Vikram, Vinu, Jain, Bhuvnesh, Zhao, Gong-Bo, and Koyama, Kazuya, E-mail: annanusca@gmail.com, E-mail: vinu@sas.upenn.edu, E-mail: gong-bo.zhao@port.ac.uk, E-mail: bjain@physics.upenn.edu, E-mail: Kazuya.Koyama@port.ac.uk. Sun . "Astrophysical tests of gravity: a screening map of the nearby universe". United States. doi:10.1088/1475-7516/2012/07/034.
@article{osti_22280043,
title = {Astrophysical tests of gravity: a screening map of the nearby universe},
author = {Cabré, Anna and Vikram, Vinu and Jain, Bhuvnesh and Zhao, Gong-Bo and Koyama, Kazuya, E-mail: annanusca@gmail.com, E-mail: vinu@sas.upenn.edu, E-mail: gong-bo.zhao@port.ac.uk, E-mail: bjain@physics.upenn.edu, E-mail: Kazuya.Koyama@port.ac.uk},
abstractNote = {Astrophysical tests of modified gravity theories in the nearby universe have been emphasized recently by Hui 2009 and Jain 2011. A key element of such tests is the screening mechanism whereby general relativity is restored in massive halos or high density environments like the Milky Way. In chameleon theories of gravity, including all f(R) models, field dwarf galaxies may be unscreened and therefore feel an extra force, as opposed to screened galaxies. The first step to study differences between screened and unscreened galaxies is to create a 3D screening map. We use N-body simulations to test and calibrate simple approximations to determine the level of screening in galaxy catalogs. Sources of systematic errors in the screening map due to observational inaccuracies are modeled and their contamination is estimated. We then apply our methods to create a map out to 200 Mpc in the Sloan Digital Sky Survey footprint using data from the Sloan survey and other sources. In two companion papers this map will be used to carry out new tests of gravity using distance indicators and the disks of dwarf galaxies. We also make our screening map publicly available.},
doi = {10.1088/1475-7516/2012/07/034},
journal = {Journal of Cosmology and Astroparticle Physics},
issn = {1475-7516},
number = 07,
volume = 2012,
place = {United States},
year = {2012},
month = {7}
}