Table 3.

Average IP Shock Parameters for Resolved and Unresolved Precursors

All Shocks Below Satisfy:
〈Mf〉up ≥ 1; 1 ≤ 〈MA〉up ≤ 3; 〈β〉up ≤ 1;
1 ≤ ℛ ≤ 3; and θBn ≥ 45°
Parameter	Xmin	Xmax	$\overline{X}$	$\tilde{X}$	σx
67/113 Shocks With Underresolved Precursorsa
〈β〉up (N/A)	0.02	0.82	0.32	0.30	0.22
θBn (deg)	46	88	69	69	11
〈Mf〉up (N/A)	1.04	2.52	1.72	1.76	0.39
〈MA〉up (N/A)	1.15	2.95	2.08	2.14	0.53
〈|Vshn|〉up (km s−1)	86	908	465	455	119
〈|Ushn|〉up (km s−1)	39	275	121	109	55
〈|Bo|〉up (nT)	2.4	17.4	7.4	6.7	3.0
〈ni〉up (cm−3)	1.6	27.8	9.3	7.6	5.8
46/113 Shocks With Resolved Precursorsb
〈β〉up (N/A)	0.04	0.66	0.32	0.36	0.17
θBn (deg)	46	88	62	61	11
〈Mf〉up (N/A)	1.02	2.22	1.57	1.59	0.33
〈MA〉up (N/A)	1.15	2.80	1.89	1.93	0.47
〈|Vshn|〉up (km s−1)	9	701	430	418	127
〈|Ushn|〉up (km s−1)	43	259	98	87	45
〈|Bo|〉up (nT)	2.1	15.6	5.7	5.1	2.5
〈ni〉up (cm−3)	1.0	29.5	7.0	6.1	5.2

^aShocks designated as YU or YM.

^bShocks designated as YS or YG or YP.