A comprehensive analysis using 9 dark matter halo models on the spiral galaxy NGC 4321

Abstract

This paper addressed the dark matter analysis on the spiral galaxy NGC 4321 (M100) by considering the nine different dark matter profiles so far lacking in the scientific literature, i.e. Pseudoisothermal, Burkert, NFW, Moore, Einasto, core-modified, DC14, coreNFW and Lucky13 profiles. In this paper, we analyzed the rotation curve analysis on the galaxy NGC 4321 by using nonlinear fitting of star, gaseous and dark matter halo equations with selected VLA HI observation data. Among the nine dark matter profiles, four dark matter profiles (DC14, Lucky13, Burkert and Moore profiles) showed declining features and hence found to be not suitable for this galaxy. This is concluded to be mainly due to the characteristics of those dark matter profiles and also due to the varying levels of problems within the inner regions fittings. For the remaining five accepted dark matter profiles, we further conducted analysis by using the reduced chi-square test. Four out of the five accepted dark matter profiles lie within the range of 0.40 < reduced chi-square < 1.70, except for the case of the core-modified profile. In addition, Pseudoisothermal profile achieved the best fitting i.e. reduced chi-square nearest to 1, mainly due to its linearity in the inner region and flatness at large radii.