I claim the ornamental design for a broom head, as shown and described.
FIG. 1 is a front view of a broom head showing my new design;
FIG. 2 is a rear view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom view thereof in which the broken lines shown representing the bristle perimeter are for illustration purposes only and form no part of the claimed design;
FIG. 5 is a side view thereof with the other side view thereof being a mirror image of the view of FIG. 5; and,
FIG. 6 is a perspective view thereof.
The broken lines in the Figures are shown for illustrative purposes only and do not form any part of the claimed design.