cathode side of the luminant body 3 and the branch 13 34 of smaller cross sectional area being placed at the anode side of the luminant body it will also be apparent from fig2 how the contactors 5 6 with leads disposed in the base 2 indicated by broken lines are connected to each respective shank 9 10 of the luminant body 3 on employment of the discharge lamp according to the invention for for example interior sterilisation of packaging containers the discharge lamp 1 is inserted down into the packaging container and is activated for a sufficient period of time effectively to neutralise all living organisms located in the packaging container so that aseptic filling of the packaging container may thereafter be undertaken in order to ensure that the lamp obtains the maximum service life and an as good as unchanged destruction effect throughout its service life the lamp is cooled during operation with the aid of coolant preferably de ionised tap water the water is led into the discharge lamp 1 via the inflow channel 7 in order via the mouth of the tube 12 to flow out in a direction towards the warmest section of the luminant body 3 i e its lower curved section 11 since the mouth of the tube 12 is not only directed towards this section of the luminant body but is also located in its immediate proximity the cooling effect at the curved section 11 of the luminant body 3 will be maximal the coolant flowing in to the liquid envelope or container 4 is thereafter forced upwards along both shanks 9 10 of the luminant.