METHOD AND ARRANGEMENT FOR AN X-RAY SOURCE

There is provided an X-ray source comprising an electron source for providing an electron beam, the electron source comprising a cathode, a Wehnelt, and an anode; an electron optic arrangement configured to deflect and focus the electron beam towards a target for generation of X-ray radiation; an arrangement for determining a quantity indicative of a width of the electron beam; and a controller operatively connected to the electron source, the electron optic arrangement, and the arrangement for determining the quantity indicative of a width of the electron beam, the controller configured to compute a quantity dependent on a divergence of the electron beam at an entrance of the electron optic arrangement based on the quantity indicative of a width of the electron beam; and apply a bias voltage to the Wehnelt such that the quantity dependent on the divergence of the electron beam at the entrance of the electron optic arrangement is adjusted towards a desired value. A corresponding method is also provided.