2025RNAAS...9..167M

The high resolution far ultraviolet spectrum of HD 145842, a newly discovered HgMn star, is compared to that of the normal star HD 152614, which has similar effective temperature, surface gravity and projected equatorial velocity. The spectrum of HD 145842 shows stronger lines of gallium, in particular the resonance line at 1414.40 Å, and a weaker resonance line of Al II at 1670.79 Å. The line synthesis of gallium , aluminium, carbon and iron lines yields the following excesses/deficiencies: +1.70 dex for gallium, -0.70 dex for aluminium, -0.52 dex for carbon and +0.00 dex for iron. These are the first measurements of the abundances of gallium and aluminium in HD 145842. They confirm the HgMn status for this star. The most recent TESS lightcurves yield a short rotational period of HD 145842, P_rot = 1.144 days, in agreement with previously published values.