form(optional)Captures whether a beam is "feathered" and in which direction.
Allowed values are:
"acc" ((accelerando) means that the secondary beams become progressively more distant
toward the end of the beam.), "mixed" ((mixed acc and rit) for beams that are "feathered" in both directions.), "rit" ((ritardando) indicates that the secondary beams get progressively closer together
toward the end of the beam.), "norm" ((normal) indicates that the secondary beams are equidistant along the course of
place(optional)Records the placement of the beam relative to the events it affects.
Value conforms to data.BEAMPLACE.
slash(optional)Indicates presence of slash through the beam.
Value conforms to data.BOOLEAN.
slope(optional)Records the slope of the beam.
Value is a decimal number.