The rotation curve of DDO 154 - A particularly acute test of the modified dynamics

view Abstract Citations (38) References (11) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Rotation Curve of DDO 154: A Particularly Acute Test of the Modified Dynamics Milgrom, Mordehai ; Braun, Erez Abstract We compare the rotation curve of DDO 154, calculated in the framework of the modified dynamics, with the observed rotation curve reported recently by Carignan and Freeman. In this context DDO 154 stands out as a very crucial test for two reasons: (1) The accelerations measured within it are, by far, the lowest reported for any galaxy that is amenable to a rotation curve analysis. One thus works in the deep, low-acceleration limit and is free of various uncertainties that occur at higher accelerations. (2) The mass of the galaxy is dominated by the contribution of H I which is measured directly (unlike that of the stars). Using the H I mass and light distribution given by Carignan and Freeman and using their inclination and adopted distance, we get a very good agreement between the calculated and observed rotation curves, with the value of the acceleration constant a₀_ ~ 1. 3 x 10^-8^ cm s^-1^, which is in agreement with earlier determinations. We also discuss some remaining uncertainties. Publication: The Astrophysical Journal Pub Date: November 1988 DOI: 10. 1086/166823 Bibcode: 1988ApJ. . . 334. . 130M Keywords: Galactic Rotation; Space Density; H I Regions; Luminosity; Astrophysics; GALAXIES: INTERNAL MOTIONS; GRAVITATION full text sources ADS | data products SIMBAD (5) NED (3)