Cascade emission in electron beam ion trap plasma of W25+ ion

•Spectra of the W25+ ion are calculated using the collisional-radiative model.•Influence of cascade emission on the formation of lines is studied.•Cascade emission boosts intensities only of a few lines in the 10-30 nm range.•Emission band at 4.5-5.3 nm is affected by the cascade emission.•Time-integrated study of the line intensities is presented.

Spectra of the W25+ ion are studied using the collisional-radiative model (CRM) with an ensuing cascade emission. It is determined that the cascade emission boosts intensities only of a few lines in the 10-30 nm range. The cascade emission is responsible for the disappearance of structure of lines at about 6 nm in the electron beam ion trap plasma. Emission band at 4.5-5.3  nm is also affected by the cascade emission. The strongest lines in the CRM spectrum correspond to 4d94f4→4f3 transitions, while 4f25d→4f3 transitions arise after the cascade emission is taken into account.