Mergers prompted by dynamics in compact, multiple-star systems: a stellar-reduction case for the massive triple TIC 470710327

TIC 470710327, a massive compact hierarchical triple-star system, was recently identified by NASA's Transiting Exoplanet Survey Satellite (TESS). 470710327 is comprised of (1.10 d) circular eclipsing binary, with total mass $\approx 10.9-13.2\ \rm{M_{\odot}}$, and more ($\approx 14-17\ \rm{M_{\odot}}$) eccentric non-eclipsing tertiary in $52.04$ d orbit. Here we present progenitor scenario for which '2+2' quadruple dynamics result Zeipel-Lidov-Kozai (ZLK) resonances that lead to contact phase the binary. In this scenario, two binary systems should form very similar manner, trigger merger either during late phases star formation or several Myr after zero-age main sequence (ZAMS), when stars begin expand. Any evidence highly-magnetised ($\sim 1-10$ kG), slowly-rotating blue main-sequence would hint towards origin. Finally, our suggests population inclined, multiple-stellar reduced into co-planar systems, via mergers, early sequence. The elucidation origin crucial understanding multiple massive-star evolution.