Space quantum vacuum radiation in a laser-particle collision

The probability of photon emission of a charged particle traversing a strong field becomes modified if vacuum polarization is considered. This feature is important for fundamental quantum electrodynamics processes present in extreme astrophysical environments, such as magnetars and black holes, and can be studied in a collision of a charged particle with a strong laser field. We show that for today's available 700~GeV (6.5~TeV) protons and the field provided by the next generation of lasers, the emission spectra peak is enhanced due to vacuum polarization effect by 30\% (suppressed by 65\%) in comparison to the traditionally considered Compton process in which vacuum polarization is neglected. This striking phenomenon offers a novel path to the laboratory-based manifestation of vacuum polarization.