An electromagnetic pulsed gas valve operating in a strong magnetic fie
ld (B = 3-6 T) is described. The valve enables one to form a plane gas
stream with Mach number M approximate to 3 and an angular divergence
approximate to 45 degrees. A high linear density nL similar to 10(19)
cm(-2) can be obtained in a gas cloud with a typical size L approximat
e to 10 cm.