Intermediate states and state transitions are another important aspect of BHB studies. The three states defined by McClintock & Remillard (2006) attempt to specify spectral and timing conditions that are quasi-stable and that appear to have distinct physical origins. There are gaps in the parameter ranges used to define these states (Table 2), and this gives rise to intermediate states. The hybrid of the hard and SPL states is particularly interesting for its correlations with radio properties (§4.3 and §5) and also with disk properties (§6.1).
Source: Remillard & McClintock 2006 ┃ X-Ray Properties… ⚬𓂃
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