Long term variability of Cygnus X-1 - V. State definitions with all sky monitors

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Table 2

Overview over all sky monitor based state definitions for Cyg X-1.

State	ASM-based^a	MAXI-based^b	BAT-based^c	GBM-based^d

Hard	c ≤ 20 ∨ c ≤ 55(h − h₀)	c_M ≤ 1.4h_M	...^e	...^f
Interm.	c > 20 ∧ 55(h − h₀) < c ≤ 350(h − h₀)	1.4h_M < c_M ≤ 8/3h_M	...^e	...^f
Soft	c > 20 ∧ c > 350(h − h₀)	8/3h_M < c_M	c_B ≤ 0.09 counts cm^-2 s^-1	f ≤ 0.6 Crab

Notes.

^(a)

With ASM 1.5−12 keV count rate c in counts s^-1, ASM (5−12 keV/1.5−3 keV) hardness h, and h₀ = 0.28.

^(b)

With MAXI 2−4 keV count rate c_M in counts s^-1 and MAXI (4−10 keV/2−4 keV) hardness h_M.

^(c)

With BAT normalized 15−50 keV countrate c_B in counts cm^-2 s^-1.

^(d)

With daily GBM 25−50 keV flux f.

^(e)

Distinguishing between hard and intermediate states is not possible based on BAT light curves alone. The source is defined as in BAT-based hard or intermediate state for c_B > 0.09 counts cm^-2 s^-1.

^(f)

Distinguishing between hard and intermediate states is not possible based on GBM daily light curves alone. The source is defined as in GBM-based hard or intermediate state for f > 0.6 Crab.

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