Probing the physics of transitional ms pulsars through X-ray and optical pulses

The Xray emission of transitional ms pulsars in the disk state is highlypeculiar and is a previously unknown outcome of the diskmagnetosphereinteraction that has yet to be understood. We recently discovered that thetransitional ms pulsar PSR J1023+0038 is also an optical pulsar (Ambrosino,Papitto et al. 2017, Nature Astronomy), strongly suggesting that amagnetospheric rotationpowered process is active. Simultaneous X ray/opticalhightemporal resolution observations are needed to finally nail down themechanism, rotation or accretion power, producing optical and Xray pulsations.We propose 2x25 ks and 2x30 ks observations of PSR J1023+0038 and 3FGL J1544.61125, simultaneously to high temporal resolution optical observations. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]