Table 5:

Infrared line fluxes I and their ratios I/I(5007 Å) to the dereddened optical [O III] 5007 Å line from the Spitzer data.

Line	Line flux I, 10-13 erg/cm2/s/pixel					Flux ratio I/I(5007 Å)
	FMK 1	FMK 2	FMK 3	FMK 4	FMK 5	Average	FMK 1	FMK 2	FMK 3	FMK 4	FMK 5
[Ar II] 6.985 m	3.8	14	17	5.6	11	0.5(1)	0.41	0.75	1.15	0.46	0.79
[Ar III] 8.991 m	0.46	2.0	1.7	0.80	1.5	0.08(3)	0.05	0.13	0.12	0.07	0.12
[S IV] 10.51 m	0.24	1.6	1.4	0.67	0.91	0.07(2)	0.025	0.11	0.10	0.06	0.07
[Ne II] 12.81 m	0.31	0.92	0.89	1.0	0.30	0.10(8)	0.04	0.07	0.07	0.08	0.025
[Ne V] 14.32 m	0.071	0.20	0.18	0.10	0.14	0.012(7)	0.009	0.012	0.012	0.009	0.014
[Ne III] 15.56 m	0.29	2.2	1.2	3.0	0.47	0.05(3)	0.009	0.03	0.03	0.05	0.006
[Fe II] 17.94 m	0.16	0.90	1.3	1.8	0.87	0.03(2)	0.005	0.015	0.03	0.04	0.013
[S III] 18.71 m	0.82	5.0	5.2	2.5	4.2	0.08(2)	0.025	0.08	0.15	0.05	0.06
[O IV] 25.91 m	2.3	13	11	12	7.2	0.20(5)	0.08	0.24	0.26	0.26	0.13
[S III] 33.48 m	0.28	1.9	2.3	0.76	0.6	0.04(1)	0.011	0.05	0.06	0.015	0.015
[Si II] 34.81 m	1.0	3.7	3.9	1.7	1.7	0.07(3)	0.04	0.10	0.11	0.03	0.04

The column ``average'' contains the ratio values averaged over the northern part of Cas A and their observed scatter, and other columns contain data for the Hurford & Fesen (1996) FMKs.
Notes: the table contains data for the strongest lines only. The regions are numbered as in Hurford & Fesen (1996) with their positions shown in Fig. 7. The ``average'' column assumes single optical line reddening correction of 200 times. Note that the pixel sizes are different for the IRS LL (5 08 or  sr,  m) and SL (1 85 or  sr,  m) modules.