We use the multi-epoch radial velocities acquired by the APOGEE survey toperform a large scale statistical study of stellar multiplicity for field starsin the Milky Way, spanning the evolutionary phases between the main sequenceand the red clump. We show that the distribution of maximum radial velocityshifts (\drvm) for APOGEE targets is a strong function of \logg, with mainsequence stars showing \drvm\ as high as $\sim$300 \kms, and steadily droppingdown to $\sim$30 \kms\ for \logg$\sim$0, as stars climb up the Red Giant Branch(RGB). Red clump stars show a distribution of \drvm\ values comparable to thatof stars at the tip of the RGB, implying they have similar multiplicitycharacteristics. The observed attrition of high \drvm\ systems in the RGB isconsistent with a lognormal period distribution in the main sequence and amultiplicity fraction of 0.35, which is truncated at an increasing period asstars become physically larger and undergo mass transfer after Roche LobeOverflow during H shell burning. The \drvm\ distributions also show that themultiplicity characteristics of field stars are metallicity dependent, withmetal-poor ([Fe/H]$\lesssim-0.5$) stars having a multiplicity fraction a factor2-3 higher than metal-rich ([Fe/H]$\gtrsim0.0$) stars. This has profoundimplications for the formation rates of interacting binaries observed byastronomical transient surveys and gravitational wave detectors, as well as thehabitability of circumbinary planets.
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