Keerthi started the Supernanogan source today. His primary goal was to test out Rick's theoretical tune calculations. He was ecstatic with the results. Rick's table gives a tentitive value for the Einzel lens. In fact the ideal value is at or even higher than the bias voltage. However, Keerthi experieced sparkdowns at those voltages. Rick's calculation gives a reasonable number for better than 50% transmission between MCIS:FC0 and IOS:FC3. The Enzel lens at full chat (10KV with the present power supply) gives a transmission of close to 90% with 11.5KV bias. So far, there are no sparkdowns. Keerthi suspects a resonance effect with the earlier sparkdowns. Presently we are observing beam and optics stability, with about 16nA of 17O3+ on IOS:FC6. I'll do some scans in a while. |