Energy levels, radiative rates, and electron impact excitation rates for transitions in OVII

Aims. <br/>In this paper we report calculations for energy levels, radiative rates, and electron impact excitation rates for transitions in O vii.<br/>Methods. <br/>The grasp (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative<br/>rates. For determining the collision strengths and subsequently the excitation rates, the Dirac atomic R-matrix code (darc) and the<br/>flexible atomic code (fac) are used.<br/>Results. <br/>Oscillator strengths, radiative rates, and line strengths are reported for all E1, E2, M1, and M2 transitions among the lowest<br/>49 levels of O vii. Collision strengths have been averaged over a Maxwellian velocity distribution, and the resulting effective collision<br/>strengths are reported over a wide temperature range below 2 × 106 K. Additionally, lifetimes are also listed for all levels.<br/>Key words.