Confronting MOND and TeVeS with strong gravitational lensing over galactic scales: An extended survey

The validity of modified Newtonian dynamics (MOND) and tensor vector scalar (TeVeS) models of modified gravity has been recently tested by using lensing techniques, with the conclusion that a nontrivial component in the form of dark matter is needed in order to match the observations. In this work, those analyses are extended by comparing lensing to stellar masses for a sample of nine strong gravitational lenses which probe galactic scales. The sample is extracted from a recent work which presents the mass profile out to a few effective radii, therefore reaching into regions which are dominated by dark matter in the standard (general relativity) scenario. A range of interpolating functions are explored to test the validity of MOND/TeVeS in these systems. Out of the nine systems, there are five robust candidates with a significant excess (higher than 50%) of lensing mass with respect to stellar mass, irrespective of the stellar initial mass function. One of these lenses (Q0957) is located at the center of a galactic cluster. This system might be accommodated in MOND/TeVeS via the addition of a hot component, like a 2 eV neutrino, which contributes over cluster scales. However, the other four robust candidates (LBQS1009, HE1104, B1600, HE2149) are located in field/group regions, so that a cold component (cold dark matter) would be required even within the MOND/TeVeS framework. Our results, therefore, do not support recent claims that these alternative scenarios to cold dark matter can survive astrophysical data.