Blue stragglers in globular clusters are abnormally massive stars that shouldhave evolved off the stellar main sequence long ago. There are two knownprocesses that can create these objects: direct stellar collisions and binaryevolution. However, the relative importance of these processes has remainedunclear. In particular, the total number of blue stragglers found in a givencluster does not seem to correlate with the predicted collision rate, providingindirect support for the binary-evolution model. Yet the radial distributionsof blue stragglers in many clusters are bimodal, with a dominant central peak:this has been interpreted as an indication that collisions do dominate bluestraggler production, at least in the high-density cluster cores. Here wereport that there is a clear, but sublinear, correlation between the number ofblue stragglers found in a cluster core and the total stellar mass containedwithin it. From this we conclude that most blue stragglers, even those found incluster cores, come from binary systems. The parent binaries, however, maythemselves have been affected by dynamical encounters. This may be the key toreconciling all of the seemingly conflicting results found to date.
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