Context : To analyze spectra of hot stars , advanced non-local thermodynamic equilibrium ( NLTE ) model-atmosphere techniques are mandatory .
Reliable atomic data is crucial for the calculation of such model atmospheres .

Aims : We aim to calculate new Sr iv-vii oscillator strengths to identify for the first time Sr spectral lines in hot white dwarf ( WD ) stars and to determine the photospheric Sr abundances .
To measure the abundances of Se , Te , and I in hot WDs , we aim to compute new Se v , Te vi , and I vi oscillator strengths .

Methods : To consider radiative and collisional bound-bound transitions of Se v , Sr iv - vii , Te vi , and I vi in our NLTE atmosphere models , we calculated oscillator strengths for these ions .

Results : We newly identified four Se v , 23 Sr v , 1 Te vi , and three I vi lines in the ultraviolet ( UV ) spectrum of RE 0503 $ - $ 289 .
We measured a photospheric Sr abundance of 6.5 ^ { +3.8 } _ { -2.4 } \times 10 ^ { -4 } ( mass fraction , 9 500 - 23 800 times solar ) .
We determined the abundances of Se ( 1.6 ^ { +0.9 } _ { -0.6 } \times 10 ^ { -3 } , 8 000 - 20 000 ) , Te ( 2.5 ^ { +1.5 } _ { -0.9 } \times 10 ^ { -4 } , 11 000 - 28 000 ) , and I ( 1.4 ^ { +0.8 } _ { -0.5 } \times 10 ^ { -5 } , 2 700 - 6 700 ) .
No Se , Sr , Te , and I line was found in the UV spectra of G191 $ - $ B2B and we could determine only upper abundance limits of approximately 100 times solar .

Conclusions : All identified Se v , Sr v , Te vi , and I vi lines in the UV spectrum of RE 0503 $ - $ 289 were simultaneously well reproduced with our newly calculated oscillator strengths .