The peculiar chemical abundance of the transitional millisecond pulsar PSR J1023+0038 – Li enhancement

Using high-resolution optical spectroscopy we determine the chemical abundance of secondary star in binary millisecond pulsar PSR J1023+0038. We measure a metallicity [Fe/H] = 0.48 +/- 0.04 which is higher than Solar value and general find that element abundances are different compared to stars X-ray binaries solar neighbourhood similar Fe content. Our results suggest was formed supernova explosion. models, where matter has been processed captured by leading anomalies, qualitatively agree with observations. Li A(Li) 3.66 0.20, anomalously high same effective temperature, irrespective age system. Furthermore, J1023+0038 Cosmic what observed young Population I so provides unambiguous evidence for fresh production. The most likely explanation interaction energy gamma-rays or relativistic protons from wind intrabinary shock CNO nuclei star's atmosphere via spallation leads substantial enrichment atmosphere.