Density and Mass Distribution of Spiral Galaxy NGC 3198

The density and mass of the spiral galaxy NGC 3198 have been studied as functions of the distance from the center of galaxy depending on its observed rotation curve. Calculation of density and mass at different radii of the galaxy NGC 3198 show that the central inner density rho 1(r) at r < r(t) (r(t) is the turn-off radius) is found to be constant rho 1 = 0.387 M-o pc(-3), while the density rho 2(r) of the outer region r > r(t) is much less than the inner region, which varies from 0.0187 M-o pc(-3) at r = 4 kpc to 0.00278 M-o pc(-3) at r = 30 kpc. On the other hand, the inner mass m1(r) at r < r(t) grows from 1.33 x 10(9) M-o at r = 0.1 kpc to a mass of 8.539 x 10(9) M-o at r = 4 kpc, while the outer mass m2(r) at r >= r(t) changes from 8.539 x 10(9) M-o at the turn-off radius r(t) to 5.262 x 10(10) M-o at r = 30 kpc of the galaxy. Finally, the behavior of the calculated density and mass is consistent with other works.