Magnetic remanence

The strength of the magnetic field that remains in a tape or magnetic particle after it is (1) exposed to a strong, external magnetic field and (2) the external field is removed. The property of a tape that determines its ability to record and store a magnetic signal. Mr is the common abbreviation for magnetic remanence. Magnetic remanence, Mr, and magnetic retentivity, Br, both refer to the ability of the tape to retain a magnetic field; however the latter is expressed in units of magnetic flux density.

[A] magnetic representation of residual information remaining on a magnetic medium after the medium has been cleared. [INFOSEC-99]