MOND rotation curves for spiral galaxies with Cepheid-based distances

¹ Kapteyn Astronomical Institute, PO Box 800, NL-9700 AV Groningen, The Netherlands
² Dpto. de Física, Univ. de Jaén, Virgen de la Cabeza 2, 23071-Jaén, Spain
³ Institute for Astronomy, 2680 Woodlawn Dr., Honolulu, HI 96822, USA

Corresponding author: R. H. Sanders, sanders@astro.rug.nl

Received: 18 February 2002
Accepted: 9 July 2002

Abstract

Rotation curves for four spiral galaxies with recently determined Cepheid-based distances are reconsidered in terms of modified Newtonian dynamics (MOND). For two of the objects, NGC 2403 and NGC 7331, the rotation curves predicted by MOND are compatible with the observed curves when these galaxies are taken to be at the Cepheid distance. For NGC 3198, the largest distance for which reasonable agreement is obtained is 10% smaller than the Cepheid-based distance; i.e., MOND clearly prefers a smaller distance. This conclusion is unaltered when new near-infrared photometry of NGC 3198 is taken as the tracer of the stellar mass distribution. For the large Sb spiral, NGC 2841, MOND requires a distance which is at least 20% larger than the Cepheid-based distance. However, the discrepancy of the Tully-Fisher and SNIa distances with the Cepheid determination casts some doubt upon the Cepheid method in this case.