Tossing Black Hole Spin Axes

The detection of double black hole (BH+BH) mergers provides a unique possibility to understand their physical properties and origin. To date, the LIGO-Virgo-KAGRA network high-frequency gravitational wave observatories have announced more than 85 BH+BH merger events (Abbott et al. 2022a). An important diagnostic feature that can be extracted from data is distribution effective inspiral spins BHs. This in clear tension with theoretical expectations both an isolated binary star origin, which traditionally predicts close-to aligned BH component (Kalogera 2000; Farr 2017), formation via dynamical interactions dense stellar environments symmetric (Mandel & O'Shaughnessy 2010; Rodriguez 2016b). Here it demonstrated evolution convincingly explain observed if BHs spin axis tossed during process core collapse massive star, similarly evidently acting newborn neutron stars. without spin-axis tossing, however, has difficulties reproducing - even alignment prior second disregarded. Based on simulations only minimum assumptions, constrains empirical made magnitudes first- second-born BHs, thereby serving better