of u03b4c close to zero and or locally have a flat slope other members of this group are shown in fig1 these are in particular pr ce and nd as well as yb above all dy and gd are suitable as members of a second group for which the color difference u03b4c increases with an increasing power see fig1 the associated color temperature in kelvin is shown in fig1 and 14 specific exemplary embodiments which relate to hoi 3 and also gdi 3 are explained in fig1 and 11 the high pressure discharge lamp with a ceramic discharge vessel is represented based on filling with 1 bar of xe 2 mg of ali 3 0 5 mg of tli and 4 mg of hoi 3 example shown by rhombi and based on filling with 1 bar of xe 2 mg of ali 3 0 5 mg of tli and 4 mg of gdi 3 example shown by stars respectively shown are u03b4c p close to zero u03b4c in units of 10 u2212 3 see fig1 and the color temperature t n in k see fig1 the two values are presented as a function of the power p in the range of from 50 to 300 w both iodides exhibit a flat profile of the color distance u03b4c p in the event of a power variation when using hoi 3 on its own the color temperature is particularly constant as a function of the power variation a suitable combination.