jQuery Chart - panes
A pane is a chart area containing series. If there are many series an a chart, they can be distributed between multiple panes.
Each object in the panes array configures a single pane. If you have several panes, we recommend you to name each pane in order to be able to refer to them afterwards.
When there are multiple panes in a chart, series need to know which pane they belong to. By default, all of them belong to the defaultPane or, if it is not specified, to the last pane in the panes array. To bind a series to another pane, name the pane and assign this name to the pane series property.