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tokens: has not taken place yet). Future observations of the disc may provide additional constraints, considering there is indirect evidence for a much larger binary population within it. For example, binaries could account for the observed radial trend in disc membership among young stars in the Galactic Centre (Naoz et al. 2018 ). The remainder of this paper is organized as follows. In Section 2 , we review the effects of mass ratio on binary disruptions. In Section 3 , we describe the approximate method we use to model disruptions. In Section 4 , we describe how the probability of not producing massive S-stars varies with binary parameters. In Section 5 , we discuss the effects of stellar disruptions. Finally, we summarize our conclusions in Section 6 . 2 MASS RATIO AND THE HILLS MECHANISM When an unequal mass binary is disrupted, the primary star’s final orbit will be closer in energy to that of the original binary than the secondary star’s. This is because the primary star is closer to the binary’s centre of mass, and experiences a smaller tidal force. Analogously, when a single star is disrupted the most tightly bound debris comes from its surface (Rees 1988 ). Stars can either gain or lose energy in the disruption, depending on the binary’s phase. The final (specific) energy of star i will be (see e.g. Kobayashi et al. 2012 ) where ε o is the initial energy of the centre-of-mass orbit, M is the mass of the SMBH, r t is the tidal radius (approximately ( M / m bin ) 1/3 a bin , where m bin and a bin are the binary mass and semimajor axis, respectively). The δ i factor is the characteristic distance between the star and the centre of mass. This is approximately qa bin /(1 + q ) for the primary and a bin /(1 + q ) for the secondary, where q is the ratio of the secondary mass to the primary mass. Thus, the post-disruption (specific) energies of the primary (star 1) and the secondary (star 2), are where k is a factor of order unity that depends on the binary’s eccentricity, phase, and orientation (see GM20). In the parabolic limit, the corresponding semimajor axes are The absolute value of the primary’s semimajor axis is larger by 1/ q . 3 MONTE CARLO EXPERIMENTS We explore how the mass and semimajor axis distribution of the bound stars depend on the properties of the progenitor binary population. In particular, we construct mock binary samples from the distributions in Table 1 . For each binary, we calculate post-disruption energies of its member stars according to equation ( 2 ), assuming the initial semimajor axis of the binary’s centre-of-mass orbit is 0.05 pc. The scatter from the binary’s phase and orientation is encapsulated by k . We use the suite of ∼500 000 archain binary disruption simulations from GM20 to construct an empirical distribution for this parameter. Although the final energies of the stars depend on the binary mass, semimajor axis, and its centre-of-mass orbit, the k -distribution will not depend on these properties. Thus,