Binary Stars Build Dark Matter Molecules ⚡ экспресс
Ultralight bosons in tight binary systems of comparable masses form gravitational 'molecules' when the separation drops below the Bohr radius; their inner region moves with the system. Numerical simulations model the birth of these structures, identify corotating zones, and compute ionization rates for different eccentricities. A semi-analytical formalism is proposed for the ionization dynamics of corotating and non-corotating parts, confirmed by simulations. Back-reaction estimates show that in the early stages, ionization dominates over gravitational-wave emission, creating a break in the background spectrum. Ionization of the corotating component is due solely to orbital ellipticity and leads to its circularization.
A pair of stars whirling in elongated orbits acts like a giant nucleus, and the cloud of dark matter around them—like an electron cloud in a molecule. This 'gravitational molecule' stretches billions of kilometers—more than from the Sun to Pluto. Its size is determined by an analog of the Niels Bohr radius, familiar from the hydrogen atom.
The motion of the stars shakes this cloud, ripping particles out of it—a process similar to atomic ionization. Due to the loss of particles, the pair's orbit gradually rounds: the ellipse becomes a circle. Notably, in the early stages, this effect can surpass the emission of gravitational waves, leaving a characteristic kink in their background.
🎯 The radius of such a 'gravitational molecule' can exceed the distance from the Sun to Pluto, even though the very concept of a radius comes from the microworld.