Electromagnetic pump

1 . An arrangement for providing a liquid metal jet in a vacuum environment comprising:

a vacuum chamber;

a nozzle arranged to provide said liquid metal jet;

a jet receiver comprised within said vacuum chamber and arranged to receive liquid metal from said liquid metal jet;

a first electromagnetic pump section comprising a first inlet and a first outlet, said first inlet having a first diameter;

a second electromagnetic pump section comprising a second inlet and a second outlet, and a pumping conduit connecting said second inlet to said second outlet, said pumping conduit having a second diameter;

wherein said first outlet is arranged to provide liquid metal to said second inlet;

characterized in that said first diameter is at least 1.8 times as large as said second diameter.

2 . The arrangement of claim 1 , further comprising a feeding conduit connecting said first inlet to said second inlet, said feeding conduit having a diameter that, along said feeding conduit, decreases from the first diameter at the first inlet to the second diameter at the second inlet.

3 . The arrangement of claim 2 , wherein the feeding conduit is continuously tapered from the first inlet to the second inlet.

4 . The arrangement of claim 1 , further comprising a connecting conduit that connects the first outlet to the second inlet.

5 . The arrangement of claim 1 , further comprising a current source for providing an electrical current to both of the first and the second electromagnetic pump sections.

6 . The arrangement of claim 5 , further comprising an electrical connection between the first and the second electromagnetic pump sections providing a path for the electrical current between the first and the second electromagnetic pump.

7 . The arrangement of claim 1 , further comprising a first current source for providing an electrical current to the first electromagnetic pump and a second current source for providing an electrical current to the second electromagnetic pump.

8 . The arrangement of claim 1 , wherein said first diameter is at least 2.5 times as large as said second diameter.

9 . A liquid metal jet radiation source, comprising:

an arrangement according to claim 1 ; and

an energy source for providing an energy beam to interact with the liquid metal jet in an interaction region such that radiation is generated;

wherein said jet receiver is arranged downstream of the interaction region in a flow direction of the liquid metal jet.

10 . The liquid metal jet radiation source of claim 9 , wherein the radiation source is an X-ray source, and wherein the energy source is an electron source for providing an electron beam to interact with the liquid metal jet such that X-ray radiation is generated.

11 . A method for providing a liquid metal jet in a vacuum environment, comprising:

collecting liquid metal in a receiver, said receiver being located in a vacuum chamber;

pumping, using a first electromagnetic pump section, the liquid metal from the receiver to a second electromagnetic pump section; and

pumping, using said second electromagnetic pump section, the liquid metal to a nozzle for generating a liquid metal jet;

wherein said first electromagnetic pump section comprises a first inlet and a first outlet, said first inlet having a first diameter, and wherein said second electromagnetic pump section comprises a second inlet and a second outlet, and a pumping conduit connecting said second inlet to said second outlet, said pumping conduit having a second diameter,

characterized in that said first diameter is at least 1.8 times as large as said second diameter.

12 . The method of claim 11 , wherein pumping, using said first electromagnetic pump section, the liquid metal from the receiver to the second electromagnetic pump section comprises pumping the liquid metal through a feeding conduit connecting said first inlet to said second inlet, said feeding conduit having a diameter that, along said feeding conduit, decreases from the first diameter at the first inlet to the second diameter at the second inlet.

13 . The method of claim 11 , wherein a common current source is used for providing electrical current to both the first and the second electromagnetic pump sections.

14 . The method of claim 11 , further comprising directing an energy beam onto the liquid metal jet to generate radiation from interaction between the energy beam and the liquid metal jet.

15 . The method of claim 14 , wherein the energy beam is an electron beam that interacts with the liquid metal jet to generate X-ray radiation.