Matter ejections behind the highs and lows of a transitional millisecond pulsar

In this talk, I will describe the results of the most extensive multiwavelength observational campaign ever carried out on the prototype of the class of transitional millisecond pulsars, PSR J1023+0038. The campaign aimed to find an explanation once and for all for the peculiar variability pattern shown by the source during its current active X-ray state. The results of the data analysis indicate that this phenomenology is due to changes in the innermost region of the accretion disc. These changes trigger the emission of discrete mass ejections, which occur on top of a compact jet, as testified by the detection of at least one short-duration millimetre flare at the high-to-low mode switch. The pulsar is subsequently re-enshrouded, completing the picture of the mode switches. Strong electromagnetic and gravitational field physics: From laboratories to early Universe / Magnon-antimagnon pair production by magnetic field inhomogeneities and the bosonic Klein effect Physics, University of Sao Paulo, Brazil. 3 Department of Physics, Tomsk State University, Russia, and Department of General and Experimental Physics, Herzen State Pedagogical University of Russia, Russia Similar to Dirac models of nanostructures, low-energy excitations in spin systems –magnons– can be described in terms of effective field theories. The theory describing antiferromagnets can be mapped into scalar massless electrodynamics with an external electromagnetic potential. Here, we consider the case of a constant inhomogeneous magnetic field applied to an antiferromagnet, whose characteristic magnetic moment plays the role of the electric charge, and magnons and antimagnons differ by the sign of the magnetic moment. In the framework of the effective description, we discuss how vacuum instability (the Schwinger effect) due to magnon-anti magnon production arises in this context. In particular, we show how to use the strong field QED with x-steps developed by the authors (SPG and DMG) to study magnon-anti magnon pair production characteristics by magnetic field inhomogeneities. Finally, we will examine specific examples and investigate the impact of the external field inhomogeneity on magnon pair production.