| One distinguished object is the head of a bunch. If the bunch contains a target object, then we pick the mode = (primary, secondary, outside) in that order. if there are multiple primaries then the lowest objID wins. if there is no target in in the bunch, then the (primary) SpecObj wins. if there is no target or specobj, then the (primary) Best obj wins. Each bunch object points to its BunchHead and all objects with the same BunchHead form a bunch. (starting with a 1.5 arcsecond radius, we do a transitive closure (friends of friends) to build the bunch. The BunchHead describes the bundle, its center point (head's RA, DEC) and the counts of bunch members of each type. |