Reverberation
Mapping (RM)
•Broad lines are photoionized by the central continuum, which varies. The line flux follows the continuum with a time lag t which
is set by the size of the broad-line
emitting region and the speed of light.
Recombination timescales are
very short, BLR stable, and continuum source small and central. Review:
Kaspi et al. (2000) studied bright
PG quasars, particularly Hβ, finding that
R=32.9(λLλ5100/1044 erg s-1)0.7 lt-days
For the Hβ
emitting gas.