2022RNAAS...6...30M

Line variations are studied in the mid-ultraviolet spectra of 78 Vir collected with IUE between phases of far-UV (FUV) maximum and FUV minimum. The mid-UV spectrum of 78 Vir is populated with low-lying transitions of iron-peak elements. The lines of Cr II and Ca II are found to be stronger at phase of FUV minimum, while the lines of Ni IIprobably vary in anti phase with those of chromium and calcium. Those of Fe IIand Mn IIdo not show convincing variations between the two phases. The analysis of these mid-ultraviolet spectra suggests that iron and manganese are uniformly distributed over the surface of 78 Vir, while chromium, calcium and nickel are not but more ultraviolet lines should be studied to confirm this.