The Binary Companion Of Young, Relativistic Pulsar J1906+0746
PSR J1906+0746 is a young pulsar in the relativistic binary with the second-shortest known orbital period, of 3.98 hours. We here present a timing study based on five years of observations, conducted with the 5 largest radio telescopes in the world, aimed at determining the companion nature. Through the measurement of three post-Keplerian orbital parameters we find the pulsar mass to be 1.291(11) M_sol, and the companion mass 1.322(11) M_sol respectively. These masses fit well in the observed collection of double neutron stars, but are also compatible with other white dwarfs around young pulsars such as J1906+0746. Neither radio pulsations nor dispersion-inducing outflows that could have further established the companion nature were detected. We derive an HI-absorption distance, which indicates that an optical confirmation of a white dwarf companion is very challenging. The pulsar is fading fast due to geodetic precession, limiting future timing improvements. We conclude that young pulsar J1906+0746 is likely part of a double neutron star, or is otherwise orbited by an older white dwarf, in an exotic system formed through two stages of mass transfer.
Digital Commons Citation
van Leeuwen, J.; Kasian, L.; Stairs, I. H.; and Lorimer, D. R., "The Binary Companion Of Young, Relativistic Pulsar J1906+0746" (2015). Faculty & Staff Scholarship. 1091.
van Leeuwen, J., Kasian, L., Stairs, I. H., Lorimer, D. R. (2015). The Binary Companion Of Young, Relativistic Pulsar J1906+0746. The Astrophysical Journal, 798(2), 118. http://doi.org/10.1088/0004-637X/798/2/118