Completing the Spin-down Measurements of Two Nearby Isolated Neutron Stars

The seven nearest thermally emitting neutron stars may be the best way to sampleneutron stars demography, and may offer the best prospects for measuring neutronstar radii. But both tasks are limited by our ignorance of their magneticfields; hence we have been determining timing solutions with Chandra and XMM.The results so far show a tight grouping of magnetic fields in a range betweennormal pulsars and magnetars. This is surprising and interesting, butlowerthanexpected spindown rates mean that for two sources spindown wasdetected only marginally. We propose two short observations of each of those twosources to complete our timing solutions. We will then have precise spindownmeasurements for all six thermally emitting neutron stars with confirmed periodicities. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]