Translated graph of reactor parameters between 1:19am and the explosion

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The data were presented in this format as an appendix of the 1986 'Legasov commission' report to the IAEA in Vienna (soon to be republished as INSAG-1). Take the lines and curves with a grain of salt, since the graph seems to be a combination of actual diagnostic data from the DREG program of the Skala on the one hand (note the circular 'bubbles'), and the results of unspecified quantitative modelling on the other. 

Large image, recommend downloading to view it

Especially curious are the movements of the three automatic control rod groups (higher Y-axis values indicate rods inserting). The provenance of these detailed rod positions is unknown, and they seem to conflict with what is described in INSAG-7. At timestamp 1:22:37, the control rod curves disagree markedly with the DREG printout, as they are inserted much deeper into the reactor. On the whole, the graph depicts a reactor with substantially more positive reactivity insertion immediately before and during the rundown test than is attested to by other sources.