SIMBAD references

Natal kicks are a matter of debate and they significantly affect the merger rate density of compact objects. Here, we present a new simple formalism for natal kicks of neutron stars (NSs) and black holes (BHs). We describe the magnitude of the kick as v_kick∝f_H05m_ejm_rem^–1, where f_H05 is a normalization factor, drawn from a Maxwellian distribution with one-dimensional rms velocity σ = 265 km s^–1, m_ej is the mass of the supernova (SN) ejecta, and m_rem is the mass of the compact object. This formalism matches the proper motions of young Galactic pulsars and can naturally account for the differences between core-collapse SNe of single stars, electron-capture SNe and ultra-stripped SNe occurring in interacting binaries. Finally, we use our new kick formalism to estimate the local merger rate density of binary NSs (R_BNS), BH-NS binaries (R_BHNS), and binary BHs (R_BBH), based on the cosmic star formation rate density and metallicity evolution. In our fiducial model, we find R_BNS ∼ 600 Gpc^–3 yr^–1, R_BHNS ∼ 10 Gpc^–3 yr^–1, and R_BBH ∼ 50 Gpc^–3 yr^–1, fairly consistent with the numbers inferred from the LIGO-Virgo collaboration.