Can MOND take a bullet? Analytical comparisons of three versions of MOND beyond spherical symmetry
Abstract
A proper test of modified Newtonian dynamics (MOND) in systems of nontrivial geometries depends on modelling subtle differences in several versions of its postulated theories. This is especially true for lensing and dynamics of barely virialized galaxy clusters with typical gravity of scale a_{0}. The original MOND formula, the classical singlefield modification of the Poisson equation, and the multifield general relativistic theory of Bekenstein (tensorvectorscalar, TeVeS) all lead to different predictions as we stray from spherical symmetry. In this paper, we study a class of analytical MONDian models for a system with a semiHernquist baryonic profile. After presenting the analytical distribution function of the baryons in spherical limits, we develop orbits and gravitational lensing of the models in nonspherical geometries. In particular, we can generate a multicentred baryonic system with a weak lensing signal resembling that of the merging galaxy cluster 1E 065756 with a bulletlike light distribution. We finally present analytical scalefree highly nonspherical models to show the subtle differences between the singlefield classical MOND theory and the multifield TeVeS theory.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 September 2006
 DOI:
 10.1111/j.13652966.2006.10668.x
 arXiv:
 arXiv:astroph/0606216
 Bibcode:
 2006MNRAS.371..138A
 Keywords:

 gravitation;
 Galaxy: kinematics and dynamics;
 Galaxy: structure;
 dark matter;
 Astrophysics
 EPrint:
 14 pages, 9 figures, accepted for publication in MNRAS