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We present a multi-passband photometric study of the Blue Straggler Star(BSS) population in the Galactic globular cluster (GC) NGC\,1261, usingavailable space- and ground-based survey data.~The inner BSS population isfound to have two distinct sequences in the color-magnitude diagram, similar todouble BSS sequences detected in other GCs. These well defined sequences arepresumably linked to single short-lived events such as core collapse, which areexpected to boost the formation of BSSs.~In agreement with this, we find a BSSsequence in NGC\,1261 which can be well reproduced individually by atheoretical model prediction of a 2 Gyr old population of stellar collisionproducts, which are expected to form in the denser inner regions duringshort-lived core contraction phases.~Additionally, we report the occurrence ofa group of BSSs with unusually blue colours in the CMD, which are consistentwith a corresponding model of a 200 Myr old population of stellar collisionproducts.~The properties of the NGC\,1261 BSS populations, including theirspatial distributions, suggest an advanced dynamical evolutionary state of thecluster, but the core of this GC does not show the classical signatures ofcore-collapse.~We argue these apparent contradictions provide evidence for apost-core-collapse bounce state seen in dynamical simulations of old GCs.

The Blue Straggler Star Population in NGC 1261: Evidence for a Post-Core-Collapse Bounce State