2.2. The Two Jet Flavors

Jets can be divided into two "flavors" with characteristically different sets of properties, as summarized in Table 1. The results in this table are taken from Bridle (1984, 1992) and Bridle & Perley (1984 and references therein).

Table 1. The properties of strong- and weak-flavor jets.

Strong-flavor	Weak-flavor
Most jets in sources with P1.4 1025 WHz-1 are of this type	Jets in sources with P1.4 1024 WHz-1 are usually of this type over most of their lengths
One-sided (> 4:1)	Two-sided (< 4:1)
B||, except at bright knots	B, except at edges (and especially outside edges of bends)
Opening angle < 4° (FWHM/D)	Opening angle > 8°
Limb-brightened, at least in well-studied cases (Cen A; M 87)	Center-brightened
Brighter per unit length in smaller sources	Similarly bright (1021.5±1 WHz-1 kpc-1) in sources of all sizes
Common in FRII quasars with P1.4 < 1024.5 WHz-1 and at bases of weak-flavor (FRI) jets	Common in weak (P1.4 < 1024.5 WHz-1) (FRI) radio galaxies Pj > 0.1 Pext
Knotty	Smooth