We investigate the amount of scatter in the Tully-Fisher relation (TFR) when using optical long-slit H rotation curves to determine the velocity widths of spiral galaxies. We study a sample of 25 galaxies in the Coma region of the sky which were shown in Bernstein et al. (1994) to exhibit an extraordinarily low scatter of 0.10 mag RMS in the I magnitude vs 21-cm width TFR. Using the same I magn...

The truncation of stellar discs is not abrupt but characterized by a continuous distancing from the exponential profile. There exists a truncation curve, t(r), ending at a truncation radius, r t. We present here a theoretical model in which it is assumed that the magnetic hypothesis explaining the flat rotation curve also explains the truncation. Once stars are born, the centripetal magnetic fo...

Using an outer rotation curve of the Galaxy, we explore the galactic constants and the mass of the Galaxy. We show that Θ0 of 200 km s −1 is more favorable than the IAU standard value of 220 km s, and also show that if Θ0 is smaller than 207 km s −1 the rotation curve beyond 2R0 is declining in Keplerian fashion. In the case of Θ0= 200 km s −1 and R0= 7.6 kpc, the total mass and the extent of t...

h −1 [75] (scale length 53 kpc). This corresponds to the H I extent. There is also a prominent bulge-like component. According to Pickering et al. [3] the rotation curve has the slowly rising shape typical of the less luminous, “dark matter dominated” LSB galaxies. This slow rise of the rotation curve in the presence of a luminous central component is in marked contrast with the rule that there...

Context. The properties of the gas in halos of galaxies constrain global models of the interstellar medium. Kinematical information is of particular interest since it is a clue to the origin of the gas. Aims. Here we report observations of the kinematics of the thick layer of the diffuse ionized gas in NGC 891 in order to determine the rotation curve of the halo gas. Methods. We have obtained a...

Curve flexibility in adolescent idiopathic scoliosis (AIS) was one of the major concerns of spinal surgeons since the evolution of surgical correction techniques. In this respect, many tried to identify which criteria denote more rigid curve. In the present study, we aimed toward determining important factors influencing AIS curve flexibility on supine bending films. We assessed radiographs of ...

Using the Tuorla-Heidelberg model for the mass distribution of the Milky Way, I determine the rotation curve predicted by MOND. The result is in good agreement with the observed terminal velocities interior to the solar radius and with estimates of the Galaxy’s rotation curve exterior thereto. There are no fit parameters: given the mass distribution, MOND provides a good match to the rotation c...