A determination of the white-dwarf masses in wide binary radio-pulsar systems

The paper concerns a determination of the mass of the white dwarf in wide binary radio-pulsar systems, including the mass of neutron star PSR 1855 + 09. The binary pulsars considered consist of systems with long orbital periods, low mass functions and circular orbits. The determination of the white-dwarf mass is based on a constraint to the orbital solution, i.e. that the giant progenitor of the present white dwarf secondary should have filled its Roche lobe while spinning up the pulsar companion by mass transfer. Employment of this constraint leads to the mass of the white dwarf in these type of binary pulsars, and to an upper limit of approx. 1.2 M solar mass to PSR 1855 + 09. (U.K.)