A Black Hole Kicked At Birth: MAXI J1305-704

Chase Kimball, Sam Imperato, Vicky Kalogera, Kyle A. Rocha, Zoheyr Doctor, Jeff J. Andrews, Aaron Dotter, Emmanouil Zapartas, Simone S. Bavera, Konstantinos Kovlakas, Tassos Fragos, Phillip M. Srivastava, Devina Misra, Meng Sun, Zepei Xing

Submitted on 3 November 2022


When a compact object is formed in a binary, any mass lost during core collapse will impart a kick on the binary's center of mass. Asymmetries in this mass loss would impart an additional natal kick on the remnant black hole or neutron star, whether it was formed in a binary or in isolation. While it is well established that neutron stars receive natal kicks upon formation, it is unclear whether black holes do as well. Here, we consider the low-mass X-ray binary MAXI J1305-704, which has been reported to have a space velocity 200 km/s. In addition to integrating its trajectory to infer its velocity upon formation of its black hole, we reconstruct its evolutionary history, accounting for recent estimates of its period, black hole mass, mass ratio, and donor effective temperature from photometric and spectroscopic observations. We find that if MAXI J1305-704 formed via isolated binary evolution in the thick Galactic disk, then its black hole received a natal kick of at least 70 km/s with 95\% confidence.


Comment: To be submitted; 9 pages, 5 figures

Subject: Astrophysics - High Energy Astrophysical Phenomena


The viable RLO2 parameter space explored with \texttt{MESA}. The colored shapes mark successful binaries (at different BH masses) that evolved to simultaneously satisfy all observational constraints on the BH and donor masses, donor effective temperature, and orbital period of \sys{} to within 2-$\sigma$. In black are unsuccessful binaries where magnetic braking was efficient, shrinking their periods throughout mass transfer. In grey are unsuccessful binaries above the bifurcation period, expanding during mass transfer.