In this case, CMDAC has prepared an alternate version of the record that differs from the original file supplied by the PI.
CMDAC's mandate is to bring the data it obtains up to a single, uniform standard. In practice, this means that in some instances we have replaced spikes or other unrealistic (in our judgement) artifacts of the data acquisition process with interpolations. In other cases runs of bad data created by a malfunctioning instrument have been excised entirely. The goal is to provide a record that is as close to ground truth as possible, which can be used with confidence by those who may not be familiar with the failure modes of the instrumentation, and who may be unable to recognize those errors in a data record.
Both the original file and the alternate, value-added version are available on this disk. The differences between them are spelled out in the metadata document. At this point you can choose to download either
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