In 1986, the National Synchrotron Light Source installed a ten-period soft X-ray "mini-undulator" as a test bed for a longer device. We have used this device as a radiation source for soft X-ray holography and scanning microscopy, both of which require high brightness for practical operation. We present here calculations and measurements of the undulator output. Using beamline X-17T, we have measured the spectral intensity and brightness of the undulator. The results are in good agreement with calculations and indicate that even a short undulator, when coupled with a low-emittance storage ring, can produce extremely bright radiation. High brightness means large spatially coherent flux. We believe our measured value of 1011 photons/s/1% BW was the highest continuous spatially coherent flux then available from any source of soft X-rays.
ASJC Scopus subject areas
- Nuclear and High Energy Physics