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tokens: them from single stars. Triple and quadruple star disruptions naturally bring binaries in the vicinity of the MBH. Fig. 6 shows the cumulative distribution function of binary S-stars semimajor axis and eccentricity as a function of a in for Model 1, which shows a clear correlation between the final and initial binary semimajor axis. More than of binary S-stars have a b ≲ 0.5 au to avoid tidal disruption by the MBH and the eccentricity cumulative distribution is nearly independent of the initial a in and is ∝ e , i.e. the eccentricity distribution is constant. Future data, as those expected by the James Webb Space Telescope, may observe near-infrared sources with higher photometric precisions, hence helping in identifying binaries in the GC. Figure 6. Cumulative distribution function of binary S-stars semimajor axis (left) and eccentricity (right) as function of a in for Model 1. More than ≈90 per cent of binary S-stars have a b ≲ 0.5 au to avoid tidal disruption by the MBH. The cumulative distribution of eccentricities is nearly independent on the initial a in and is ∝ e , i.e. the eccentricity distribution is constant. 4 DISCUSSIONS AND CONCLUSIONS Most of the observed HVSs support the standard Hills scenario, but the main-sequence HVS HE0437-543 and the candidate HVB require different production mechanisms than the standard binary disruption. While HE0437-5439 is likely to come from the centre of the Large Magellanic Cloud (Erkal et al. 2018 ), the candidate HVB as well as the other HVSs whose traveltimes exceed their main-sequence lifetime would require disruption of triple starsby the MBH, which would produce a HVB that can later evolve into a blue straggler star as a consequence of binary evolution (Perets 2009 ). However, the recent detailed N -body simulations byFragione Gualandris ( 2018 ) have showed that the ejection rate is too low to explain these hypervelocity outliers. In this work, we discussed the 2+2 quadruple tidal disruption scenario by means of high-accuracy scattering experiments. While less abundant than triple stars, 2+2 quadruple stars constitute of the stars in the solar neighbourhood (Tokovinin 2014a , b ) and have been shown to have interesting dynamics dealing with white dwarf-white dwarf collisions (Fang et al. 2018 ) and gravitational wave emission (Seto 2018 ). We studied a wide range of parameters of the quadruple stars and performed simulations with both point masses and finite stellar radii. We found that only a very small fraction () of encounters results in the ejection of a HVB. Taking into account that the estimated ejection rate for the Hills mechanism is (Yu Tremaine 2003 ) and that 2+2 quadruple stars are roughly a third of triple stars, we conclude that also 2+2 quadruple disruption leads to a HVB production rate of , similarly to the triple disruption scenario. We conclude that quadruple disruption, as long as triple disruption, is an unlikely source of HVBs, which would require a non-GC