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Beam Synchronous Process Variables (PVs) are signals that are tied to the beam pulse that generated them. RTBSA uses this feature to build a pulse by pulse "picture" of the beam so that we can see correlations between signals that would otherwise be hidden.
Background
What is a PV?
It's kind of a short hand. PV stands for "Process Variable." We have a lot of devices on site, and those devices generate a lot of data. BPMs (beam position monitors), for example, constantly monitor where the beam is relative to the center of the beam pipe. One singular BPM, however, has a lot of signals that it reads out (chief among them x position, y position, and charge), and each one of those signals has a channel dedicated to reading it. It's kinda analogous to TV channels for a BPM TV - x position is on channel 2, y position is on channel 3, etc (except that the channel names are a little more complicated, like BPMS:LI24:801:X). Those channels are PVs.
Note: There are some devices that only have one signal that they read out (and therefore only on PV associated with them)
What does it mean to be tagged to a pulse?
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