The flat limit of rotational velocity (v<sub>φ</sub>) approximately equal to the “edge”-velocity of a galaxy is related to the baryonic mass (M<sub>B</sub>) via the T-F relationship w...The flat limit of rotational velocity (v<sub>φ</sub>) approximately equal to the “edge”-velocity of a galaxy is related to the baryonic mass (M<sub>B</sub>) via the T-F relationship with n ≈ 4. We explore the connection between mass and the limiting velocity in the framework of general relativity (GR) using the Weyl metric for axially-symmetric galaxies that are supported entirely by their rotational motion. While for small distances from the center, the Newtonian description is accurate as one moves beyond the (baryonic) edge of the galaxy, Lenz’s law and non-linearity of the gravitational field inherent in GR not only lead to a flat velocity (obviating its Keplerian fall), but also provide its tight log-log relationship with the enclosed (baryonic) mass.展开更多
The BESⅢCollaboration has recently published a new precise measurement of the time-like neutron form factor(FF)[1].In the light of the remarkable accuracy and of the wideness of the explored kinematical range,these d...The BESⅢCollaboration has recently published a new precise measurement of the time-like neutron form factor(FF)[1].In the light of the remarkable accuracy and of the wideness of the explored kinematical range,these data represent an unprecedented tool for highlighting and studying specific features of the neutron FF.Until a few years ago,the only available data were those obtained by the FENICE experiment at Frascati,in the’90s[2].展开更多
文摘The flat limit of rotational velocity (v<sub>φ</sub>) approximately equal to the “edge”-velocity of a galaxy is related to the baryonic mass (M<sub>B</sub>) via the T-F relationship with n ≈ 4. We explore the connection between mass and the limiting velocity in the framework of general relativity (GR) using the Weyl metric for axially-symmetric galaxies that are supported entirely by their rotational motion. While for small distances from the center, the Newtonian description is accurate as one moves beyond the (baryonic) edge of the galaxy, Lenz’s law and non-linearity of the gravitational field inherent in GR not only lead to a flat velocity (obviating its Keplerian fall), but also provide its tight log-log relationship with the enclosed (baryonic) mass.
文摘The BESⅢCollaboration has recently published a new precise measurement of the time-like neutron form factor(FF)[1].In the light of the remarkable accuracy and of the wideness of the explored kinematical range,these data represent an unprecedented tool for highlighting and studying specific features of the neutron FF.Until a few years ago,the only available data were those obtained by the FENICE experiment at Frascati,in the’90s[2].