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Astrophysical Jets
Simulates the bulk motion of relativistic jets coming out of a microquasar.
The jets are modeled here as a pair of jets moving away from a central source.
The two jets always move in opposite directions.
The size and color of the blobs indicates the relative brightness.
Interesting to note:
- the further the motion is from transverse, the greater the differences in the two jets.
- the increase in brightness for the approaching jet can be very high when the motion is nearly face-on.
- the decrease in brightness of the receding jet often makes it too dim to be detected (this sometimes called Doppler favoritism in favor of the approaching jet).
- for pure transverse motion, the brightness is not the same as the central source, even when the brightness is
input as 1. This is because the doppler factor is 1/Γ for transverse motion.
Here
is the above diagram for GRS1915+105, a black hole about 11,000 parsecs distant.
Note that if the approaching jet were more face-on, it would be much brighter. (More info here).
Explanatory Notes
Brightness Exponent
The change in brightness depends on the Doppler factor raised to a certain power (exponent).
That exponent takes different values, depending on the character of the emitter.
θ, sp, bri
The apparent angle, apparent speed, and relative apparent brightness of the blob.