Speaker
Description
High-mass X-ray binaries (HMXBs) are systems in which a neutron star or black hole accretes material from a massive companion. HMXBs are expected to have experienced a supernova in their evolution. The impulsive kick associated with this event should affect the space velocity of the system in a way that depends on the nature and state of the progenitor binary. Here, we test whether the different evolutionary histories of HMXBs have left a detectable imprint on their peculiar velocities ($V_{\rm pec}$). Using data from ${\it Gaia}$ Data Release 3 (${\it Gaia}$ DR3), we find that BeXRBs predominantly exhibit lower peculiar velocities ($V_{\rm pec} \lesssim 40$ km s$^{-1}$), while SgXRBs are preferentially associated with higher velocities ($V_{\rm pec} \gtrsim 40$ km s$^{-1}$). This kinematic segregation is statistically significant and may reflect differences in natal kick magnitudes between these subclasses, linked to distinct supernova and progenitor scenarios. These findings extend previous inferences based on two-dimensional kinematics from ${\it Hipparcos}$, and may be explained by the differing nature of the respective progenitors systems between the source classes at the instant of supernova.
