Pulsed H sup - Beams from Penning SPS (Surface-Plasma Sources) Sources Equipped with Circular Emitters.

摘要

We report the H sup - beam currents and emittances produced when Penning Surface-Plasma Sources (SPS), equipped with circular emitters, are pulsed at /approximately/1% duty factor. Two sources are now under investigation: the small-angle source (SAS) and the 4X source. The 4X source is designed to test the plasma scaling laws for Penning SPS; SAS is the 1X device. The 0.16 cm sup 3 discharge volume of the SAS is /approximately/30 times smaller than that of the 4X source, 4.6 cm sup 3 . With a 0.25-cm-diam circular emitter, the SAS produces 82 mA of 27-keV H sup - beam with normalized rms emittance of 0.0053 x 0.0056 ( pi /center dot/cm/center dot/mrad) sup 2 . With a 0.26-cm-diam circular emitter, the 4X source produces 50 mA of 29-keV H sup - beam with emittance of 0.0049 x 0.0050 ( pi /center dot/cm/center dot/mrad) sup 2 . The measured data are compared with the predictions of the ion-optical code SNOW. 10 refs., 7 figs., 1 tab. (ERA citation 14:013401)