The number of beamlines developed at NSRRC has been increasing roughly two beamlines per year since 1993, the year when there were only three photon beamlines in use, 1m-SNM, LSGM, and HSGM, after the Taiwan Light Source (TLS) was first commissioned and started operation. As of November 2003, there are twenty-eight beamlines in operation, including two hard X-ray beamlines SP12B and SP12U located at SPring-8, and five new beamlines under construction.
The beamline development at NSRRC has gone through two phases. In phase one we provided enough number of multiple-purpose beamlines to satisfy the most common needs of our user community. In phase two, besides construction of enough beamlines, we were able to provide adequate beam time for all the research experiments, meanwhile creating special beamlines to meet the specific requirements of advanced experiments. Since the storage ring of TLS is designed for generating excellent photon spectrum in the VUV and soft X-ray regions, at first we designed and constructed VUV and soft X-ray beamlines for research in these energy regions. After that, several beamlines providing photon energies from soft to hard X-rays were developed using the radiation sources from bending magnets and a wiggler insertion device to support X-ray research in Taiwan. These were followed by several white-light beamlines built for applied research and high performance undulator beamlines for special scientific research.
The spectrum in the hard X-ray region was later extended further into higher energies with the construction of two hard X-ray beamlines at SPring-8 in Japan through an international collaboration program. Recently, the number of X-ray beamline grows rapidly because there is still a high demand for hard X-ray beamlines from domestic users, and the technology of constructing a compact and high-field insertion device for generating hard X-rays in the medium-energy storage ring has matured. Three protein beamlines are currently under construction: the central beamline BL13B is for high throughput biological crystallography measurements; the two side-branched beamlines, BL13A and BL13C, are for high-resolution protein structure studies. In addition, one very special soft X-ray beamline EPU-AGM, designed for photon-in and photon-out experiments such as soft X-ray emission and inelastic scattering experiments, is also under construction.
When the new X-ray beamlines finish the construction and commission in the winter of 2003, the photon spectrum provided by all the beamlines in operation will cover a whole energy range from infrared, VUV, soft X-ray, to hard X-ray. The photon spectrum available to our users ranges from mid-infrared (about 20 μm) to 30 keV at TLS, and extends up to higher than 70 keV at SPring-8. There are more than 45 specialized end-stations developed for various types of experiments that utilize these beamlines. Details of these end-stations can be found in the NSRRC home page at http://users.nsrrc.org.tw under Research Facility/Beamlines & End Stations.
At the end of year 2004, we will have 32 beamlines in operation, including 4 diagnostic beamlines. We will then have enough beamlines and beam time to satisfy all the needs from domestic users. The beamline development will be greatly slowed down then, unless further requests arise as a result of fast growth of our users community or a special request for an advanced experiment. Up to now, the beamline development is nearly performed entirely by the beamline scientists and engineers of NSRRC because of the shortage of experienced people available in domestic user community. We now have enough people trained in beamline development; therefore, future beamline should be able developed by any research team, including the people trained at NSRRC, from university or industry company.