• K. Zengin, A.K. Çiftçi, R. Çiftçi
  Ankara University, Faculty of Sciences, Tandogan/Ankara

The Turkish Accelerator Complex (TAC) is a project for accelerator based fundamental and applied researches supported by Turkish State Planning Organization (DPT). The proposed complex is consisted of 1 GeV electron linac and 3.56 GeV positron ring for a charm factory and a few GeV proton linac. Apart from the particle factory, it is also planned to produce synchrotron radiation from positron ring. In this study the lattice structure design of the positron storage ring is made to produce the third generation synchrotron light. The parameters of complementary undulators and wigglers are determined. It is shown that the insertion devices with the proposed parameter sets produce maximal spectral brightness to cover 10 eV - 100 keV photon energy range.

• A. Mostacci, R. Da Re, L. Palumbo
  Rome University La Sapienza, Roma
• D. Alesini, L. Ficcadenti, B. Spataro
  INFN/LNF, Frascati (Roma)

We discuss the use of non resonant bead pull technique for measuring fields in standing wave accelerating structures. From the Steele perturbation theory, one can derive the relation between the magnitude and phase of the field in the cavity and the complex reflection coefficient. The effect of the bead size, the calibration of the bead and the comparison with the more common resonant techniques are addressed. As an example, we discuss the measurement on a X-band bi-periodic cavity proposed for linearizing emittance at the Frascati photo-injector SPARC.

• I. Pinayev, O. Singh
  BNL, Upton, Long Island, New York
• G. Decker
  ANL, Argonne

Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contracts DE-AC02-98CH10886 and DE-AC02-06CH11357.

The NSLS-II Light Source being built at Brookhaven National Laboratory requires submicron stability of the electron orbit in the storage ring in order to utilize fully very small emittances and electron beam sizes. This sets high stability requirements for beam position monitors and a program has been initiated for the purpose of characterizing RF beam position monitor (BPM) receivers in use at other light sources. Present state-of-the-art performance will be contrasted with more recently available technologies. The details of the program and preliminary results are presented.

• A. Kosicek, M. Znidarcic
  I-Tech, Solkan
• S. Bassanese
  ELETTRA, Basovizza

Libera Brilliance is a standard device for beam position monitoring on circular synchrotron light sources. Initially, the idea of optimizing its signal processing for the single bunch measurement came from the users community. This was afterwards followed by the idea of using it on transfer lines on the same 3rd generation light sources as well as on injector system for the FELs. The device can be used on pickup buttons and on striplines. The single pass functionality is contained in newest Libera Brilliance software Release 2.0, no hardware changes are needed. The measurement principles and first measurements with results are presented.

• C.H. Kuo, J. Chen, Y.-S. Cheng, P.C. Chiu, K.T. Hsu, K.H. Hu, D. Lee
  NSRRC, Hsinchu

Commissioning of new digital BPM system for TLS is done recently. The new BPM system could support functionalities of turn by turn data, post-mortem and 10Hz slow data acquisition. 10 kHz fast data translation through Liberas grouping mechanism also succeeded to acquire all bpm data and integrate into the orbit feedback system. Various tests are performed systematically to confirm its performance and reliability and will be discussed in this report. We also present the functionalities and infrastructure of the related diagnostic tools. It could record 10 sec orbit data simultaneously via hardware and software event trigger at 10 kHz. Turn by turn and post mortem are also supported through embedded EPICS IOC. More integrated software tools and environment will continue to be developed for future operation.