A target for producing polarized 21Na by optical pumping

We describe a target used to produce 21Na, a 22.5 s half-life positron emitter, in 2.5 bar of 20Ne gas. The 21Na was subsequently polarized in situ using a pulsed dye laser, with a maximum nuclear vector polarization |〈J〉| = 0.70(2). The 20Ne gas also serves as a buffer, increasing the diffusion time to the target chamber walls to about 12 s. Integrating over this time interval, the target gives an average activity of greater than 106 s−1 with |〈J〉| = 0.62.