• R. Bartolini, A.I. Baldwin, M. Belgroune, I.P.S. Martin, J.H. Rowland, B. Singh
  Diamond, Oxfordshire
• J.K. Jones
  CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire

• M. Takao, M. Masaki, J. Schimizu, K. Soutome, S. Takano, H. Tanaka
  JASRI/SPring-8, Hyogo

• J.M. Thompson, A. Roodman
  SLAC, Menlo Park, California
• W. Kozanecki
  CEA/DSM/DAPNIA, Gif-sur-Yvette

We present measurements of the effective vertical emittance and IP beta function in the PEP-II Asymmetric B Factory. These beam parameters are extracted from fits to the longitudinal dependence of the luminosity and of the vertical luminous size, measured using e⁺ e^- –> mu+ mu- events recorded in the Babar detector. The results are compared, for different sets of machine conditions, to accelerator-based measurements of the optical functions of the two beams.

• Y.T. Yan, Y. Cai
  SLAC, Menlo Park, California

Eigen-mode coupling ellipses' tilt angles and axis ratios can be precisely measured with a Model-Independent Analysis (MIA) of the turn-by-turn BPM data from resonance excitation of the betatron motion. For each BPM location one can measure 4 parameters from the two resonance excitation, which completely describe the linear coupling of the location. Results from application to PEP-II storage rings are presented.

• V. Sajaev
  ANL, Argonne, Illinois
• V. Lebedev, V. Nagaslaev, A. Valishev
  Fermilab, Batavia, Illinois

Optics measurements have played an important role in improving the performance of the FNAL Tevatron collider. Initial optics measurements were performed using a small number of differential orbits, which allowed us to carry out the first round of optics corrections. However, because of insufficient accuracy, it was decided to apply the response matrix analysis method for further optics improvements. The response matrix program developed at ANL has been expanded to include coupling – the essential feature required to describe the Tevatron optics. The results of the optics calibration are presented and compared to local beta function measurements.

• B.X. Yang, M. Borland, W. Guo, K.C. Harkay, V. Sajaev
  ANL, Argonne, Illinois

We present experimental studies of synchro-betatron-coupled electron beam motion in the Advanced Photon Source storage ring. We used a vertical kicker to start the beam motion. When the vertical chromaticity is nonzero, electrons with different initial synchrotron phases have slightly different betatron frequencies from the synchronous particle, resulting in a dramatic progression of bunch-shape distortion. Depending on the chromaticity and the time following the kick, images ranging from a simple vertical tilt in the bunch to more complicated twists and bends are seen with a visible light streak camera. Turn-by-turn beam position monitor data were taken as well. We found that the experimental observations are well described by the synchro-betatron-coupled equations of motion. We are investigating the potential of using the tilted bunch to generate picosecond x-ray pulses. Also note that the fast increase in vertical beam size after the kick is dominated by the internal synchro-betatron-coupled motion of the electron bunch. Experimentally this increase could be easily confused with decoherence of vertical motion if the bunch is only imaged head-on.

• D. Dong, C.G. Huang, Z. Zusheng
  IHEP Beijing, Beijing

In this paper we will discuss Einstein's tide force predicted by Einstein's general relativity, how the new tide force would affect the beam orbits in a storage ring, and how to pick up and recognize it from the beam signals in a storage ring. The result shows this effect can be accumulated by the charged particle beam in a storage ring, it is a very interesting result.

• P. Wesolowski, I. Birkel, E. Huttel, A.-S. Müller, M. Pont, F. Pérez
  FZK, Karlsruhe

• W.K. Lau, L.-H. Chang, C.W. Chen, H.Y. Chen, P.J. Chou, K.-T. Hsu, S.Y. Hsu, T.-T. Yang
  NSRRC, Hsinchu
• M. Dehler
  PSI, Villigen

• G.A. Amatuni, Y.L. Martirosyan, R.H. Mikaelyan, V.M. Tsakanov, A. Vardanyan
  CANDLE, Yerevan

• G. Huang, W.-H. Huang, S. Zheng
  Tsinghua University, Beijing
• J.Q. Wang, D.M. Zhou
  IHEP Beijing, Beijing

A coaxial line impedance measurement platform is developed for BEPCII. A pair of gradual change impedance matching section is designed and fabricated by numerical control milling machine. The special designed RF connector is applied to strengthen the inner conductor. The algorithm of TRL calibration is applied in the system to avoid the usage of a reference pipe for each device under test. The measurement is accomplished by a VNA under the control of the software written in LabView.

• I. Hwang, M. Yoon
  POSTECH, Pohang, Kyungbuk
• Y.J. Han, E.-S. Kim, J.S. Yang
  PAL, Pohang, Kyungbuk

• N. Mityanina
  BINP SB RAS, Novosibirsk

• P.J. Chou, J. Chen, K.-T. Hsu, C.-C. Kuo, C. Wang, M.-H. Wang
  NSRRC, Hsinchu

• Y.K. Wu, J. Li
  DU/FEL, Durham, North Carolina
• J. Wu
  SLAC, Menlo Park, California

This paper reports first observations and measurements of anomalous hollow electron beams in a storage ring. In a lattice with a negative chromaticity, hollow electron beams consisting of a solid core beam inside and a large ring beam outside have been created and studied in the Duke storage ring. We report the detailed measurements of the hollow beam phenomenon, including its distinct image pattern, spectrum signature, and its evolution with time. By capturing the post-instability bursting beam, the hollow beam is a unique model system for studying the transverse instabilities, in particular, the interplay of the wake field and the lattice nonlinearity. In addition, the hollow beam can be used as a powerful tool to study the linear and nonlinear particle dynamics in the storage ring.

• D.M. Zhou, W. Kang, J.Q. Wang, L.J. Zhou
  IHEP Beijing, Beijing
• G. Huang
  TUB, Beijing

A longitudinal impedance measurement system was established for the BEPCII. The measurements, done in the frequency domain, are based on the coaxial wire method using HP/Agilent 8720ES network analyzer. The applications of the TRL calibration technique and absorbers were investigated to find a good approach for impedance measurements. The impedance, larger than 20 Ohm and below 6 GHz, can be measured using the TRL calibration technique in the experiment. And better measurement results were got using the reference pipes with the absorbers. So, this system satisfies the requirements of the BEPCII. This paper gives a review on this impedance measurements system for the BEPCII. The measurements results show that there are no serious impedance problems for BEPCII bellows and injection kickers, agreeing well with the numerical simulations. More improvements on this system are in progress.

• W. Kang, Y. Hao
  IHEP Beijing, Beijing

• T.-C. Fan, C.-S. Hwang, F.-Y. Lin
  NSRRC, Hsinchu

• L. Li, W. Chen, G. Ni, X.J. Sun
  IHEP Beijing, Beijing

• D. Shuman, W. Barry, S. Prestemon, R.D. Schlueter, C. Steier, G.D. Stover
  LBNL, Berkeley, California

Stray field from an eddy current septum magnet adversely affects the circulating beam and can be reduced using several techniques. The stray field time history typically has a fast rise section followed by a long exponential decay section when pulsed with a half sine drive current. Changing the drive current pulse to a full sine has the effect of both reducing peak stray field magnitude by ~3x, and producing a quick decay from this peak to a lower field level which then has a similar long decay time constant as that from the half sine only drive current pulse. A method for tuning the second half sine (reverse) drive current pulse to eliminate the long exponential decay section is given.

• C.-H. Chang, H.-H. Chen, T.-C. Fan, M.-H. Huang, C.-S. Hwang, J.C. Jan, W.P. Li, F.-Y. Lin, H.-C. Su
  NSRRC, Hsinchu

• I.P. Pinayev, T.V. Shaftan
  BNL, Upton, Long Island, New York

Third generation light sources require top-off operation in order to provide proper stability of the photon beam. In this paper we present the conceptual design of the fast pulsed magnets used for injection into the 3 GeV storage ring.

• V.G. Khachatryan, A. Petrosyan
  CANDLE, Yerevan

• D. Teytelman
  SLAC, Menlo Park, California

Super B-factory designs under consideration expect to reach luminosities in the 10³⁵ - 10³⁶ range. The dramatic luminosity increase relative to the existing B-factories is achieved, in part, by raising the beam currents stored in the electron and positron rings. For such machines to succeed it is necessary to consider in the RF system design not only the gap voltage and beam power, but also the beam loading effects. The main effects are the synchronous phase transients due to the uneven ring filling patterns and the longitudinal coupled-bunch instabilities driven by the fundamental impedance of the RF cavities. A systematic approach to predicting such effects and for optimizing the RF system design will be presented. Existing as well as promising new techniques for reducing the effects of heavy beam loading will be described and illustrated with examples from the existing storage rings including PEP-II, KEKB, and DAFNE.

• T.-Y. Lee
  PAL, Pohang, Kyungbuk

• R. Li, Y.S. Derbenev
  Jefferson Lab, Newport News, Virginia

The canonical formulation and the cancellation effect for bunch dynamics under collective interaction on a curved orbit were presented in Ref. [*]. Some possible controversial representations of the cancellation effect were later addressed by Geloni et al.** In this study, we discuss all the points raised in Ref. [**] based on our canonical treatment, and show how these points can be perceived from the view point of the cancellation picture.

*R. Li and Ya. S. Derbenev, Jefferson Laboratory Report No. LJAB-TN-02-054, 2003. **G. Geloni et al., DESY Report No. DESY 03-165, 2003.

• B.X. Yang, A.H. Lumpkin
  ANL, Argonne, Illinois

The Advanced Photon Source (APS) is a third generation hard x-ray source serving a large user community. In order to characterize the high-brilliance beams, the APS diagnostics beamlines have been developed into a full photon diagnostics suite. We will describe the design and capabilities of the APS visible light imaging line, the bend magnet x-ray pinhole camera, and a unique diagnostics undulator beamline. Their primary functions are to support the APS user operations by providing information on beam sizes (20 - 100 micrometers), divergence (3 – 25 microradians), and bunch length (20 – 50 ps). Through the use of examples, we will show how these complementary imaging tools are used to visualize the electron dynamics and investigate beam instabilities. Special emphasis will be put on the use of undulator radiation, which is uniquely suitable for time-resolved imaging of electron beam with high spatial resolution, and for measurements of longitudinal beam properties such as beam energy spread and momentum compaction.

• Y. Iwasaki, S. Koda, T. Okajima, Y. Takabayashi, T. Tomimasu, K. Yoshida
  Saga Synchrotron Light Source, Industry Promotion Division, Saga City
• H. Ohgaki
  Kyoto IAE, Kyoto

• T. Takahashi, M. Izawa, S. Sakanaka, K. Umemori
  KEK, Ibaraki
• T. Koseki
  RIKEN/RARF/CC, Saitama

• G.J. Waldschmidt, N.P. Di Monte, D. Horan, L.H. Morrison, G. Pile
  ANL, Argonne, Illinois

Higher-order-mode dampers were recently installed in the storage ring rf cavities at the Advanced Photon Source to eliminate longitudinal coupled-bunch instability. It was discovered that the 540-MHz cavity dipole mode created beam instability at beam currents in excess of 85 mA causing horizontal emittance blowup. Methods of compensating for the instability by detuning the cavities and adjusting the cavity water temperature were becoming more difficult at higher beam currents as tests were performed to prepare for eventual 300-mA beam current operation. Electric field passive dampers located on the median plane of each cavity were determined to be the most promising solution. Simulation models were created and verified with low-power testing of the dampers. High-power testing of the dampers as well as conditioning of the damper ceramic load were also performed at the APS 352-MHz rf test stand and compared with simulation results. Preliminary test results will be discussed.

• J. Watanabe, K. Nakayama, K. S. Sato, H. Suzuki
  Toshiba, Yokohama
• M. Izawa
  KEK, Ibaraki
• A. Jackson, G. LeBlanc, K. Zingre
  ASP, Clayton, Victoria
• T. Koseki
  RIKEN/RARF/CC, Saitama
• N. Nakamura, H. Sakai, H. Takaki
  ISSP/SRL, Chiba

• S.A. Belomestnykh, R.P.K. Kaplan, H. Padamsee, P. Quigley, J.J.R. Reilly, J. Sears, V. Veshcherevich
  Cornell University, Laboratory for Elementary-Particle Physics, Ithaca, New York
• S. Bauer, M. Pekeler, H. Vogel
  ACCEL, Bergisch Gladbach
• L.-H. Chang, C.-T. Chen, F.-Z. Hsiao, M.-C. Lin, G.-H. Luo, C. Wang, T.-T. Yang, M.-S. Yeh
  NSRRC, Hsinchu
• E. Matias, J. Stampe, M.S. de Jong
  CLS, Saskatoon, Saskatchewan

Upon signing a technology transfer agreement with Cornell University, ACCEL began producing turn-key 500 MHz superconducting cavity systems. Four such cryomodules have been delivered, commissioned and installed in accelerators for operation to date. Two more cryomodules are scheduled for testing in early 2005. One of them will be put in operation at Canadian Light Source (CLS); the other will serve as a spare at Taiwan Light Source (TLS). The commissioning results and operational experience with the cryomodules in CESR, CLS and TLS are presented.

• F.-Z. Hsiao, S. H. Chang, W. S. Chiou, H.C. Li
  NSRRC, Hsinchu

• S.-P. Kao, C.R. Chen, F.-Z. Hsiao, J.P. Wang
  NSRRC, Hsinchu

• R.H.A. Farias, J.F. Citadini, M.J. Ferreira, J.G.R.S. Franco, A.F.A. Gouveia, L.C. Jahnel, L. Liu, R.T. Neuenschwander, X.R. Resende, P.F. Tavares, G. Tosin
  LNLS, Campinas
• N.P. Abreu
  UNICAMP, Campinas, São Paulo

We present the results of the commissioning of a 28-pole 2 T Hybrid Wiggler at the 1.37 GeV electron storage ring of the Brazilian Synchrotron Light Source. The wiggler will be used mainly for protein crystallography and was optimized for the production of 12 keV photons. The very high field and relatively large gap (22 mm) of this insertion device led to a magnetic design that includes large main and side magnets and heavily saturated poles. We present the results of the commissioning with beam, with special attention to the correction of the large linear tune-shift perturbations produced by the wiggler as well as on the reduction of beam lifetime at full energy. Since the injection at the LNLS storage ring is performed at 500 MeV we also focus on the effects of non-linearities and their impact on injection efficiency.

• K.H. Gil, J.Y. Choi, C.W. Chung, Y.-C. Kim, H.-S. Lee
  PAL, Pohang, Kyungbuk

• M. Emamian, M.D. Busch, S. Mikhailov
  DU/FEL, Durham, North Carolina
• N. Gavrilov
  BINP SB RAS, Novosibirsk

This paper presents the methodology and initial results for mechanical alignment of the booster synchrotron for the Duke FEL storage ring. The booster is a compact design and requires special considerations for alignment. The magnetic and vacuum elements of the arcs have been designed for alignment by a laser tracker system. A parametric 3D design package has been used to determine target coordinates. These target coordinates evolve from design goals to physically verified dimensions by modifying the parametric model to match mechanical measurement data after fabrication. By utilizing the functionality of the laser tracker system and a parametric 3D modeler, a direct and efficient measurement and alignment technique has been developed for a complex geometry.

• V. Popov, S.M. Hartman, S. Mikhailov, O. Oakeley, P.W. Wallace, Y.K. Wu
  DU/FEL, Durham, North Carolina

The next generation electromagnetic OK-5/Duke storage ring FEL wigglers require three 3kA/70V power supplies with current stability about 20 ppm and current ripples less than 20ppm in their full operating range. Duke FEL Laboratory acquired three out-of-service thyristor controllable power supplies (Transrex, 5kA/100V) which was built almost 30 years ago. The existing archaic firing circuit, lack of any output voltage filtering and outdated DCCT, would not be able to meet the above requirements.To deliver the desirable high performance with very limited funds, all three T-Rex power supplies have been completely rebuilt in house at DFELL. Modern high stability electronic components and a Danfysik DCCT with a high current stability have been used. New symmetrical firing circuit, efficient passive LC filter and reliable transformer-coupled active filter are used to reduce output current ripples to an appropriate level. At the present time, the first refurbished power supply in operation since August, 2004 with good overall performance. The power supply testing results of this unit will also be presented in this paper.

• V. Popov, S.M. Hartman, S. Mikhailov, O. Oakeley, P.W. Wallace, Y.K. Wu
  DU/FEL, Durham, North Carolina

The on-going Duke storage ring upgrades and the development of a new booster synchrotron injection require more than 100 units of high performance unipolar and bipolar trim power supplies in the current range of -15A to +15A. However, most of the trim power supplies on the market do not deliver two critical performance features simultaneously: a high current stability and a low current noise.An in-house trim power supply development program is then put in force to design, fabricate, and test low cost linear power supplies with current stability about 100 ppm and current ripples less than 100 ppm in a broad band. A set of unipolar power supplies (0-12A) have been designed, fabricated and successfully tested. Since August, 2004 they have been used in storage ring operation with excellent performance. The prototype of bipolar power supplies (± 15 A) has been designed and tested as well. The main design principles and their performance results of both unipolar and bipolar supplies will be presented in this paper.

• G.Y. Kurkin
  BINP SB RAS, Novosibirsk
• P. Wang
  DU/FEL, Durham, North Carolina

• G.Y. Kurkin, V.S. Arbuzov, A. Bushuev, N. Gavrilov, E.I. Gorniker, E. Kenjebulatov, M.A. Kholopov, A.A. Kondakov, Ya.G. Kruchkov, S.A. Krutikhin, I.V. Kuptsov, L.A. Mironenko, N. Mityanina, S.V. Motygin, V.N. Osipov, V. Petrov, A.M. Pilan, A.M. Popov, E. Rotov, I. Sedlyarov, A.G. Tribendis, V. Volkov
  BINP SB RAS, Novosibirsk
• S. Mikhailov, P.W. Wallace, P. Wang
  DU/FEL, Durham, North Carolina

• M. Liepe, S.A. Belomestnykh, J. Dobbins, R.P.K. Kaplan, C.R. Strohman, B.K. Stuhl
  Cornell University, Laboratory for Elementary-Particle Physics, Ithaca, New York

A new digital control system has been developed, providing great flexibility, high computational power and low latency for a wide range of control and data acquisition applications. This system is now installed in the CESR storage ring and stabilizes the vector sum field of two of the superconducting CESR 500 MHz cavities and the output power from the driving klystron. The installed control system includes in-house developed digital and RF hardware, very fast feedback and feedforward control, a state machine for automatic start-up and trip recovery, cw and pulsed mode operation, fast quench detection, and cavity frequency control. Several months of continuous operation have proven high reliability of the system. The achieved field stability surpasses requirements.

• K. Jin, Y. An, L. Feng, G. Huang, G. Liu, G. Wang, X. Zeng
  USTC/NSRL, Hefei, Anhui

• S. Kwiatkowski, K.M. Baptiste
  LBNL, Berkeley, California

ALS is one of the first third generation synchrotron light sources which has been operating since 1993 at Berkeley Lab. In the present ALS operation scenario 1.5GeV electron beam is injected from the booster into the storage ring every 8 hours where is accelerated to the final energy of 1.9GeV. The beam decays between fills from 400mA to 200mA with the time average current of 250mA. In order to increase the beam brighthess ALS team plans to increase the beam current to 500mA and maintain it constant during machine operation ("Top-Off" mode of operation). This operation scenario will require full energy injection from the booster ring into the storage ring and constant operation of the injector (10 bunches with the total charge of 1nC every 30 to 35 seconds). In this paper we will present the results of the ALS injector RF system analysis fo Top-Off mode of operation and describe the way we intent to implement the necessary modifications to the booster RF system.

• B. A. Aminov, A. Borisov, S. K. Kolesov, H. Piel
  CRE, Wuppertal
• M. Pekeler, C. Piel
  ACCEL, Bergisch Gladbach

• C. Pasotti, A. Fabris, M. Svandrlik
  ELETTRA, Basovizza, Trieste

• A. Jackson
  ASP, Clayton, Victoria

• Z. Zhao, H. Ding, H. Xu
  SINAP, Shanghai

• P.F. Tavares, J.A. Brum
  LNLS, Campinas

• V.M. Tsakanov
  CANDLE, Yerevan

• M.J. Ferreira, O.R. Bagnato, R.O. Ferraz, F. R. Francisco, A. L. Gobbi, R.M. Seraphim, M.B. Silva
  LNLS, Campinas

Following the upgrade of the LNLS injector system with the addition of a 500 MeV booster synchrotron,the storage ring in-vacuum ferrite injection kicker magnets started to show overheating due the interaction with high frequency electromagnetic fields induced by the electron beam. In this paper, we describe the design of a new ceramic chamber for the kickers which minimize this effect by decreasing the coupling impedance of the kickers and their interaction with the electron beam.

• K. Zheng, W. Li, J.H. Liu, L. Liu, B. Sun, J.H. Wang, Y.L. Yang
  USTC/NSRL, Hefei, Anhui

In this paper, we introduce a bunch tracing system which is based on a bunch-by-bunch (BxB) measurement system in Hefei Light Source (HLS), and present the analysis of the experiment results. Using an in-phase gate signal and a double balance mixer to control an external trigger of ADC, we test the reliability of the BxB system. By this system, we can trace all marked bunches in a set time slot or in manual burst mode. We can record all bunches’ data during the injection, ramping, wiggler excitation and normal operation, and provide a powerful facility for machine study.

• P. Kuske
  BESSY GmbH, Berlin

Following the pioneering work at the ALS* frequency map analysis was performed at the light source BESSY. With altogether 7 families of sextupole magnets available in the storage ring, amplitude dependent tune shifts can be made rather small. Therefore, the impact of fringe fields of dipole and quadrupole magnets as well as systematic octupole and decapole field components of the quadrupole and sextupole magnets used in addition as horizontal, vertical and skew gradient correctors are clearly visible in the measured maps. Insertion devices with their known systematic and usually unknown random non-linear field components impact the appearance of the frequency maps even more strongly. In the talk the current status of the experiments as well as the results of the theoretical modeling will be presented.

*"Global Dynamics of the Advanced Light Source Revealed through Experimental Frequency Map Analysis," D. Robin, et al., Phys. Rev. Lett. 85, 558 (2000).

• C. Steier, D. Robin
  LBNL, Berkeley, California
• W. Decking
  DESY, Hamburg
• J. Laskar
  IMCCE, Paris
• L.S.N. Nadolski
  SOLEIL, Gif-sur-Yvette
• Y.K. Wu
  DU/FEL, Durham, North Carolina

The momentum aperture of a storage ring is a very important parameter that strongly influences the performance, especially the beam lifetime. For the special case of synchrotron light sources with small emittance like the Advanced Light Source (ALS), the momentum aperture depends strongly on the transverse dynamics. It is very sensitive to machine conditions such as the tunes, chromaticities, lattice symmetry, and spurious coupling, since depending on those conditions the Touschek scattered particles explore different resonance regions in the phase space. In light sources, the momentum aperture usually also depends strongly on the vertical physical aperture. Applying frequency analysis techniques in simulations and for turn-by-turn orbit measurement data provides a very powerful tool to measure and understand limitations of the dynamic momentum aperture. The techniques presented are applicable to other light sources, as well as damping rings and many types of colliders.

• Y. Papaphilippou, L. Farvacque, J.-L. Revol, V. Serriere
  ESRF, Grenoble
• S.-L. Bailey
  The College of William and Mary, Williamsburg

• C. Biscari, D. Alesini, G. Benedetti, M.E. Biagini, R. Boni, M. Boscolo, A. Clozza, G.O. Delle Monache, G. Di Pirro, A. Drago, A. Gallo, A. Ghigo, S. Guiducci, M. Incurvati, C. Ligi, F. Marcellini, G. Mazzitelli, C. Milardi, L. Pellegrino, M.A. Preger, P. Raimondi, R. Ricci, C. Sanelli, M. Serio, F. Sgamma, B. Spataro, A. Stecchi, A. Stella, C. Vaccarezza, M. Vescovi, M. Zobov
  INFN/LNF, Frascati (Roma)
• J.M. Byrd, F. Sannibale
  LBNL, Berkeley, California
• J.D. Fox, D. Teytelman
  SLAC, Menlo Park, California
• E. Levichev, P.A. Piminov, D.N. Shatilov
  BINP SB RAS, Novosibirsk
• C. Pagani
  INFN/LASA, Segrate (MI)

• K. Holldack, S. Khan, T. Quast
  BESSY GmbH, Berlin
• R. Mitzner
  Universität Muenster, Physikalisches Institut, Muenster

The laser-induced energy modulation of relativistic electrons in the BESSY II storage ring was studied by temporal and spectral characterization of femtosecond far infrared (THz) pulses being emitted due to the fact that dispersive elements convert the energy modulation into a longitudinal density modulation. Bunch shapes down to 3 ps and phase noise effects as well as the length of the femtosecond density modulation and its temporal decay were measured. The THz diagnostics is crucial for the operation of the recently commissioned undulator based "femtosecond slicing" source at BESSY.

• E. Huttel, A. Ben Kalefa, I. Birkel, A.-S. Müller, P. Wesolowski
  FZK, Karlsruhe
• M. Giovannozzi
  CERN, Geneva
• M. Pont, F. Pérez
  CELLS, Bellaterra (Cerdanyola del Vallès)

• A.-S. Müller, I. Birkel, B. Gasharova, E. Huttel, R. Kubat, Y.-L. Mathis, W. Mexner, D.A. Moss, F. Pérez, R. Rossmanith, P. Wesolowski, M. Wuensch
  FZK, Karlsruhe
• C. J. Hirschmugl
  UWM, Milwaukee, Wisconsin
• M. Pont
  CELLS, Bellaterra (Cerdanyola del Vallès)

• S. Sakanaka, T. Mitsuhashi, T. Obina, K. Umemori
  KEK, Ibaraki

*M. Bai et al., Phys. Rev. ST Accel. Beams 3, 064001 (2000).

• E.S. Park, J. Choi, H.-S. Kang, M. Kim, E.-H. Lee, T.-Y. Lee
  PAL, Pohang, Kyungbuk

• G.-H. Luo, H.-P. Chang, C.-C. Kuo, K.-K. Lin, H.-J. Tsai, M.-H. Wang
  NSRRC, Hsinchu

• V.P. Suller
  CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
• M.G. Fedurin, P. Jines, T.A. Miller
  LSU/CAMD, Baton Rouge, Louisiana

• R. Bartolini, A.I. Baldwin, M. Belgroune, C. Christou, V.C. Kempson, I.P.S. Martin, J.H. Rowland, B. Singh
  Diamond, Oxfordshire
• D.J. Holder, J.K. Jones, S.L. Smith, J.A. Varley, N.G. Wyles
  CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire

• G. Decker, N. Sereno
  ANL, Argonne, Illinois

A method for obtaining very short pulses using modulation of the accelerating voltage gradient is described and simulation results given. The idea is to operate the two rf stations with a phase separation adjusted so that the synchronous particle resides on the crest of one of the sources. Phase modulation of the on-crest system at twice the synchrotron frequency induces a longitudinal bunch shape oscillation with significantly reduced bunch length occurring twice each synchrotron period. Pulsed and steady-state operation will be discussed using various accelerator parameters.

• C. Yao, M. Borland, A. Grelick, A.H. Lumpkin, N. Sereno
  ANL, Argonne, Illinois

A particle accumulator ring (PAR) is used at the Advanced Photon Source (APS) to collect multiple linac bunches and compress them into a 0.3-ns (rms) single bunch for booster injection. A 9.77-MHz fundamental rf system and a 117.3-MHz harmonic rf system are employed for initial beam capture and bunch length compression. Satellite bunches with very low charge form due to rf phase drifts or beam loading change. These satellites, when injected into the booster and then into the storage ring (SR), cause bunch impurity at three buckets from the target bucket. Storage ring and booster bunch cleaning was tried but proved to be difficult due to the top-up mode of operation in the storage ring and tune drift in the booster synchrotron. Recently we implemented a PAR bunch-cleaning system with tune-modulated harmonic rf knockout. Preliminary tests gave a measured SR bunch purity of better than 10-6, which shows that the cleaning method is feasible and could achieve a bunch purity goal of 10-8. This report describes the system configuration, test results, and system performance.

• T.V. Shaftan, A. Blednykh, S. Chouhan, E.D. Johnson, S.L. Kramer, S. Krinsky, J.B. Murphy, I.P. Pinayev, S. Pjerov, B. Podobedov, G. Rakowsky, J. Rose, T. Tanabe, J.-M. Wang, X.J. Wang, L.-H. Yu
  BNL, Upton, Long Island, New York

• H. Nishimura, R.J. Donahue, D. Robin, C. Steier
  LBNL, Berkeley, California

The ALS is planning to operate with top-off injection at higher beam currents and smaller vertical beam size. As part of a radiation safety study for top-off, we carried out two kinds of tracking studies: (1) to confirm that the injected beam cannot go into users’ photon beam lines, and (2) to control the location of beam dump when the storage ring RF is tripped. (1) is done by tracking electrons from a photon beam line to the injection sector inversely by including the magnetic field profiles, varying the field strength with geometric aperture limits to conclude that it is impossible. (2) is done by tracking an electron with radiation in the 6-dim space for different combinations of vertical scrapers for the realistic lattice with errors.

• H. Nishimura, T. Scarvie
  LBNL, Berkeley, California

New storage ring lattices have traditionally been commissioned using a trial-and-error approach, where the number of turns circulated is slowly built up until enough beam is stored to correct the orbit. We have found that by combining the calculated response matrix of magnet misalignments from a linear model of a new lattice with the measured steering magnet response matrix used during normal operations, it is possible to make an educated guess for the steering magnet settings that will immediately allow beam circulation in the new lattice. “Effective” magnet misalignments are simply those that are sufficiently close to the real misalignments to make the first guess good enough to circulate beam; the relationship between effective and real magnet misalignments is also discussed in the paper. This predictive steering method makes the process of establishing enough circulating beam for SVD-based orbit correction in a new lattice very efficient.

• D. Robin, J.M. Byrd, P. Fischer, P.A. Heimann, D.H. Kim, S. Kwiatkowski, D. Li, F. Sannibale, C. Steier, W. Wan, W. Wittmer, A. Zholents
  LBNL, Berkeley, California

A scheme is studied for producing ps length pulses of x-ray radiation from the Advanced Light Source (ALS) using two RF deflecting cavities. The cavities create vertical displacements of electrons correlated with their longitudinal position in the bunch. The two cavities separated by 180 degrees of vertical phase advance. This allows the vertical kick from one cavity to be compensated by the vertical kick of the other. The location of the cavities corresponds to the end of one straight section and the beginning of the following straight section. Halfway between the cavities a bending magnet source is located. The radiation from the bend can be compressed to ~1 ps in duration.

• G.D. Stover, K.M. Baptiste, W. Barry, J. Gath, J. Julian, S. Kwiatkowski, S. Prestemon, R.D. Schlueter, D. Shuman, C. Steier
  LBNL, Berkeley, California

ALS top-off mode of operation will require injection of the electron beam from the Booster Ring into the Storage Ring at the full ALS energy level of 1.9GeV. Currently the Booster delivers a beam at 1.5GeV to the Storage Ring where it is then ramped to the full energy and stored for the user operation. The higher Booster beam energy will require the pulse magnets in the Booster and Storage Rings to operate at proportionally higher magnetic gap fields. Our group studied and tested the possible design and installation modifications required to operate the magnets and drivers at "top-off" levels. Our results and experiments show that with minor electrical modifications all the existing pulse magnet systems can be used at the higher energy levels, and the increased operational stresses should have a negligible impact on magnet reliability. Furthermore, simple electrical modifications to the storage ring thick septum will greatly reduce the present level of septum stray leakage fields into the storage ring beam.

• F. Wang, dc. Cheever, M. Farkhondeh, W.A. Franklin, W. Graves, E. Ihloff, C. Tschalaer, D. Wang, D. Wang, T. Zwart, J. van der Laan
  MIT, Middleton, Massachusetts
• G.L. Carr, B. Podobedov
  BNL, Upton, Long Island, New York
• F. Sannibale
  LBNL, Berkeley, California

• Y.K. Wu, M.D. Busch, M. Emamian, J.F. Faircloth, J. Gustavsson, S.M. Hartman, C. Howell, M. Johnson, J. Li, S. Mikhailov, O. Oakeley, J. Patterson, M. Pentico, V. Popov, V. Rathbone, G. Swift, P.W. Wallace, P. Wang
  DU/FEL, Durham, North Carolina

The Duke FEL lab operates a unique UV/VUV storage ring FEL and an FEL driven, nearly monochromatic, highly polarized, high intensity Compton gamma-ray source. The Duke storage ring light source is undergoing several phases of upgrade in order to significantly improve light source capabilities and performance. The 2004 phase included an upgrade of the RF system with a high-order mode damped RF cavity and a new 34 meter long straight section lattice to host new FEL wigglers in the next phase. This upgrade was completed in August 2004 and storage ring and light source commissioning were completed in November 2004. This paper will provide an overview of this upgrade project and report our commissioning experience of the storage ring and light sources.

• H. Zhang, L. Wang
  USTC/NSRL, Hefei, Anhui
• Y.L. Li
  DESY, Hamburg

• C.J. Bocchetta, D. Bulfone, G. D'Auria, G. De Ninno, B. Diviacco, A. Fabris, R. Fabris, M. Ferianis, A. Gambitta, F. Iazzourene, E. Karantzoulis, M. Lonza, F.M. Mazzolini, M. Svandrlik, L. Tosi, R. Visintini, D.Z. Zangrando
  ELETTRA, Basovizza, Trieste

• S. Hashimoto, A. Ando
  University of Hyogo, Laboratory of Advanced Science and Technology for Industry (LASTI), Kamigori-cho, Ako-gun, Hyogo
• Y. Shoji
  LASTI, Ako-gun, Hyogo
• T. Takahashi
  KURRI, Osaka

• D. Einfeld, E. Al-Dmour, J. Campmany, M. Muñoz, M. Pont, F. Pérez
  CELLS, Bellaterra (Cerdanyola del Vallès)

• T.-S. F. Wang, J. T. Kwan
  LANL, Los Alamos, New Mexico

The technical feasibility of an explosives detection system based on the nuclear resonance absorption (NRA) of gamma rays in nitrogen-rich materials was demonstrated at Los Alamos National Laboratory (LANL) in 1993 by using an RFQ proton accelerator and a tomographic imaging prototype.* The study is being continued recently to examine deployment of such an active interrogation system in realistic scenarios. The approach is to use a cyclotron and electron-cooling-equipped storage rings(s) to provide the high quality and high current proton beam needed in a practical application. In this work, we investigate the storage ring requirements for a variant of the airport luggage inspection system considered in the earlier LANL experiments. Estimations are carried out based on the required inspection throughput, the gamma ray yield, the proton beam emittance growth due to scattering with the photon-production target, beam current limit in the storage ring, and the electron cooling rate. Studies using scaling and reasonable parameter values indicate that it is possible to use no more than a few storage rings in a practical NRA luggage inspection system.

*R. E. Morgado et al., SPIE Conf. Proc. 2092, International Society for Optical Engineering, Bellingham, WA, 1993, p. 503.

• R. Merl, T. Spickermann
  LANL, Los Alamos, New Mexico

Custom instrumentation has been developed at the Los Alamos Neutron Science Center to measure the Proton Storage Ring (PSR) beam energy. The PSR accumulates up to 4x10¹³ protons from the linear accelerator for delivery to a spallation neutron source. The energy of the beam injected into the PSR must be adjusted so that the revolution frequency matches the ring buncher frequency, otherwise a large momentum spread will cause increased losses in high-dispersion areas. Errors in injected beam energy appear as deviations from the ideal revolution frequency. A low-cost, custom, reconfigurable VME module has been adapted to calculate the PSR revolution frequency in real-time. The module connects directly to an analog wall current monitor output and uses analog signal conditioning electronics, an analog to digital converter, field programmable gate arrays, and an embedded floating-point digital signal processor to calculate the revolution frequency. This is an improvement over the previously used method of manually measuring the frequency with an oscilloscope. Accelerator physicists can now simply observe the PSR frequency, which is dependent on beam energy, on a control room display.

LA-UR-04-8661.

• R.J. Smith, M. Dufau, B.G. Martlew
  CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
• G. Cox
  CCLRC/DL, Daresbury, Warrington, Cheshire

The installation of a new APPLE/II undulator with user controlled polarisation has necessitated the upgrade of the Electron Beam Position Monitoring (EBPM) detector electronics and position feedback systems. The upgraded installation will utilise commercially available multiplexed detection electronics, coupled with a two phase control system interface replacement. Phase one involves the replacement of the existing G-64 based read-back system with direct analogue connections to the VME beam steering and Feedback system. This allows existing monitoring and feedback software to work with improved update rates (~ 1Hz -> ~ 8Hz). Phase two will see the installation of new high-performance control system front ends and will allow real-time monitoring at up to 100Hz and provide snapshots with resolution of 1-10 KHz.

• R.M. Lill, F. Lenkszus, E. Norum, A. Pietryla
  ANL, Argonne, Illinois

The Advanced Photon Source (APS) is a third-generation synchrotron light source in its tenth year of operation. The storage ring employs three different types of beam position monitor (BPM) systems to measure and control beam motion. The monopulse radio frequency (rf) BPM is a broadband (10 MHz) system, which is considered to be the backbone of orbit control. The rf BPM system was designed to measure single-turn and multi-turn beam positions. The rf BPMs are presently suffering from an aging data acquisition system. By replacing only the data acquisition we will revitalize this system for another decade and demonstrate a cost-effective approach to improved beam stability, reliability, and enhanced postmortem capabilities. In this paper we present the design of an eight-channel ADC/digitizer VXI board with a sampling rate of 88 MHz (per channel) and 14-bit resolution coupled with a field-programmable gate array and embedded central processing. We will discuss the upgrade system specifications, design, and prototype test results.

• A.H. Lumpkin, B.X. Yang
  ANL, Argonne, Illinois
• F. Sakamoto
  UTNL, Ibaraki

The Advanced Photon Source (APS) is a hard x-ray user facility based on a 7-GeV storage ring (SR). To accommodate the requests of the diverse user community, the APS normally runs with a 24-singlets fill pattern, a hybrid fill with a singlet and eight septuplets, or a 324-singlet fill pattern. In all cases the total stored beam current is 100 mA, with the lattice providing a natural emittance of about 2.5 nm rad. The first two patterns are used with a top-up mode that involves injection of one pulse of ~2.5 nC every two minutes into the designated SR bucket. Since the partition of bunch current varies for the different fills as well as the loading of the rf cavities, dual-sweep streak camera measurements (Hamamatsu model C5680) have been performed to characterize the average and individual bunch lengths in the fill patterns and the phase slew that occurs within the patterns. The bunch lengths vary from 32 ps (σ) within the septuplet to 50 ps (σ) for the singlet in the hybrid fill. The phase slew is significant in the hybrid fill across the eight septuplets. Example streak images of each pattern will be presented and discussed.

• M. Hahn
  ESRF, Grenoble
• R. Kersevan
  ORNL, Oak Ridge, Tennessee

• E.-S. Kim, Y.J. Han, J.Y. Huang, I.S. Ko, P.C.D. Park, S.J. Park
  PAL, Pohang, Kyungbuk
• H. Hukuma, H. Ikeda
  KEK, Ibaraki

• K.R. Kim, C.W. Chung, H.S. Han, H.-G. Kim, Y.-C. Kim, I.S. Ko, B.H. Lee
  PAL, Pohang, Kyungbuk

The cooling water system has been utilized for absorbing heat generated by a multitude of electromagnetic power delivering networks at PLS. The separate cooling water distribution systems for the storage ring, beam transport line and linear accelerator have been operated with a different operating temperature of supplying water. All water used for heat removal from the accelerator components are deionised and filtered to provide with over 2 MO-cm specific resistance. The operating pressures and flows of input water are also controlled with flow balancing scheme at a specified range. The operating temperature of components in the accelerator is sustained as tight as below ±0.1 deg C to minimize the influence of temperature fluctuation on the beam energy and stability. Although the PLS cooling systems were initially installed with a high degree of flexibility to allow for easy maintenance, a number of system improvements have been employed to enhance operational reliability and to incorporate the newly developed operating interfaces such as EPICS accelerator control systems. The important design and operational features of PLS cooling water systems are presented as well as lessons learned from around 10-years normal operation.

• J.-C. Chang, Z.-D. Tsai
  NSRRC, Hsinchu
• J.-R. Chen
  NTHU, Hsinchu
• M. Ke
  NTUT, Taipei

• D.-J. Wang, H.C. Ho, Z.-D. Tsai, J. Wang
  NSRRC, Hsinchu

• F.T. Degasperi
  FATEC-SP, Sao Paulo, SP
• M.N. Martins, J. Takahashi
  USP/LAL, Bairro Butantan
• L.L. Verardi
  IBILCE - UNESP, Sao Jose do Rio Preto, SP

This work presents numerical results for the pressure field distribution along the axis of conical tube with outgassing plus a transient degassing. Several areas of applied physics deal with problems in high-vacuum and ultra high-vacuum technology that present tubular form. In many cases one finds conical tubes, which are frequently present in particle accelerators, colliders, storage rings and several electron devices. This work presents and describes in detail the pressure field in a conical tube with a transient gas source, for instance, when particles from the beam hit the walls, plus the steady state outgassing. Mathematical and physical formulations are detailed, and the boundary conditions are discussed. These concepts and approach are applied to usual realistic cases, with typical laboratory dimensions.

• A.Z. Chen, T. G. Anderson, B.M. Hanna
  Fermilab, Batavia, Illinois

NEG pumping strips were installed inside four Tevatron B2 Magnets in order to improve the vacuum environment in B2 magnets that have embedded unbakable vacuum chamber. The prelimary results shown the total presure in that region was significant reduced. Complelte testing and opertation results will be available soon.

• Y. Wang, L. Fan, C. Y. Guan, D. M. Jiang, J. P. Wang, W. Wei, F. Y. Zhao
  USTC/NSRL, Hefei, Anhui

• Y.-H. Liu, J.-C. Chang, J.-R. Chen, Y. Lin, Z.-D. Tsai
  NSRRC, Hsinchu

The purpose of this paper is to declare the improvement on electrical and grounding systems in NSRRC. In electrical power system, an Automated Voltage Regulator (AVR) was established to RF system in 2003. The variation of voltage supply from Taiwan Power Company (TPC) is reduced from 3% to 0.2% through the AVR system. And a Supervisory Control and Data Acquisition (SCADA) system was also setup to monitoring the electrical power conditions in each power station. After the high precision grounding systems were constructed in 2004, the stability of beam line was raised. For comprehending the grounding current and noise control, a grounding monitoring system with 32 channels was built in the storage ring. The grounding currents of 4 kickers, one septum and grounding bus are on-line acquisition. Two Electromagnetic Field (EMF) apparatuses were also installed to collect electrical and magnetic fields in the R1 section. It was observed that the electromagnetic field was correlated to grounding currents in certain locations. Injection effects were clearly found in most monitored data. Some improvement works, including expansion of the grounding monitoring system composing analytical software will integrate in the next step.

• J.H. Wang, H. He, W. Li, J.H. Liu, L. Liu, B. Sun, Y.L. Yang, K. Zheng, Z.R. Zhou
  USTC/NSRL, Hefei, Anhui

• J.H. Wang, W. Li, J.H. Liu, L. Liu, B. Sun, Y.L. Yang, K. Zheng
  USTC/NSRL, Hefei, Anhui

• L. Wang, G. Feng, W. Li, H. Xu, H. Zhang
  USTC/NSRL, Hefei, Anhui

• Y.L. Yang, J.H. Liu, L. Liu, B. Sun, J.H. Wang, K. Zheng
  USTC/NSRL, Hefei, Anhui

• E. Matias, R. Berg, T. Johnson, R. Tanner, T. Wilson, G. Wright, H.Z. Zhang
  CLS, Saskatoon, Saskatchewan

• L.S.N. Nadolski, J. Chinkumo, K. Ho, N.L. Leclercq, M.O. Ounsy, S. Petit
  SOLEIL, Gif-sur-Yvette

The SOLEIL control system, namely TANGO developed in collaboration with ESRF, is now mature and stable. TANGO has also been chosen now by several other laboratories. High-level control applications implemented in the control room for the storage ring, the two transfer lines, and the booster will be described in this paper. Three kinds of tools for commissioning are used. First the generic TANGO tools (alarms, simple graphical control applications), which allow us to control in a simple way any TANGO Device Server. Secondly a Matlab Middle Layer (adapted from ALS and SPEAR3): Matlab is fully interconnected with TANGO; it is used primarily for writing Physics control applications. Finally Globalscreen, a commercial SCADA software devoted for building operation applications has been selected (panels for controlling or displaying setpoint, readback values, status of equipments). In addition an overview of the historical and short-term databases for the accelerators will be given. They have been developed in house and tested during the first commissioning.

• A. Lehrach, S. An, K. Bongardt, J. Dietrich, R. Eichhorn, B. Lorentz, R. Maier, S. Martin, D. Prasuhn, Y. Senichev, E.A. Senicheva, H. Stockhorst, R. Tölle, E. Zaplatin
  FZJ, Jülich
• O. Boine-Frankenheim, A. Dolinskii, M. Steck
  GSI, Darmstadt
• B. Gålnander, D. Reistad
  TSL, Uppsala
• F.H. Hinterberger
  Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik,, Bonn

• S. Mikhailov, M.D. Busch, M. Emamian, J.F. Faircloth, S.M. Hartman, J. Li, V. Popov, G. Swift, V. Vylet, P.W. Wallace, P. Wang, Y.K. Wu
  DU/FEL, Durham, North Carolina
• O. Anchugov, N. Gavrilov, G.Y. Kurkin, Yu. Matveev, D. Shvedov, N. Vinokurov
  BINP SB RAS, Protvino, Moscow Region

This paper presents the current status of the booster synchrotron for the Duke FEL storage ring. The booster will provide full energy injection into the storage ring in a wide energy range from 0.27 to 1.2 GeV. When operating the Duke FEL storage ring as the High Intensity Gamma Source (HIGS) to produce gamma photons above 20 MeV with Compton scattering, continuous electron loss occurs. The top-off mode operation of the booster injector will enable the continuous operation of the HIGS facility by replenishing the lost electrons. The design requirement for a compact booster with the single bunch extraction capability remains a challenge for the machine development. Presently, the booster project is in the installation phase. The magnetic elements, vacuum chambers, injection and extraction kickers have been fabricated in the Budker Institute of Nuclear Physics, Russia. The diagnostic and control system is being developed in the FEL lab, Duke University. The commissioning of the booster synchrotron is planned for fall 2005.

• K.-I. Kanazawa, H. Fukuma, H. Hisamatsu, Y. Suetsugu
  KEK, Ibaraki

• T. Kikuchi, S. Kawata
  Utsunomiya University, Utsunomiya
• K. Horioka
  TIT, Yokohama
• T. Katayama
  CNS, Saitama

• D. Schmied, E. Burtin, P. Guerin, M. Hahn, R. Kersevan
  ESRF, Grenoble

• Y. Tanimoto, T. Nogami, T. Obina
  KEK, Ibaraki

• G.Y. Kurkin
  BINP SB RAS, Novosibirsk
• S.M. Hartman, S. Mikhailov, Y.K. Wu
  DU/FEL, Durham, North Carolina
• I.P. Pinayev
  BNL, Upton, Long Island, New York

A dedicated booster synchrotron is being constructed at the Duke FEL Laboratory to provide full energy injection into the main electron storage ring. A new timing system has been developed to coordinate the injection of electron bunches from the linac to the booster, the ramping of energy in the booster, and extraction of bunches into the main ring. The timing system will allow the extraction of any bunch in the booster into any selected bucket in the main ring to provide top-off injection for any of the various operational bunch patterns of the main ring. A new master oscillator has also been developed for the RF system of the booster. The oscillator may be tuned independently or phase-locked to the master oscillator of the main ring. The issues of the soft phase locking process of the new master oscillator are discussed. The timing system and new oscillator have been fabricated and tested and are ready for operation.

• C.R. Chen, F.D. Chang, S.-P. Kao, Joseph. Liu, R.J. Sheu, J.P. Wang
  NSRRC, Hsinchu

• S.M. Hartman, S. Mikhailov, Y.K. Wu
  DU/FEL, Durham, North Carolina

The Duke FEL is developing a booster synchrotron to provide full energy injection into the Duke electron storage ring. In this paper, we describe the development of the control system for the booster. Requirements include the competing needs of simple and reliable turn-key operation for the machine as a booster; and the sophistication and flexibility of operation of the machine as a storage ring for commissioning, machine studies and as a light source. To simplify operations and machine studies, the high level controls will present the system in terms of the physics quantities of the accelerator, allowing a tight integration between the physics model and the low level hardware control, as we have previously implemented for Duke storage ring.

• S.M. Hartman
  DU/FEL, Durham, North Carolina

We analyze some recent experiences with commercial off the shelf (COTS) I/O hardware modules, comparing manufacturer specifications with our in-house measurements. Discrepancies between quoted specifications and measured performance under accelerator laboratory conditions have been observed. In some cases, design or manufacturing faults have been found which could have impact on the overall performance of the accelerator.

• G. Liu, X. Bao, C. Li, W. Li, J. Wang, Xie. Xie, K. Xuan
  USTC/NSRL, Hefei, Anhui
• J. Li
  DU/FEL, Durham, North Carolina

• H. Ohgaki
  Kyoto IAE, Kyoto
• Y. Iwasaki, S. Koda, Y. Takabayashi, T. Tomimasu, K. Yoshida
  Saga Synchrotron Light Source, Industry Promotion Division, Saga City
• H. Toyokawa
  AIST, Ibaraki

• M. Borland
  ANL, Argonne, Illinois

The code {\tt elegant} is widely used for simulation of linacs for drivers for free-electron lasers. Less well known is that elegant is also a very capable code for simulation of storage rings. In this paper, we show a newly-developed graphical user interface that allows the user to easily take advantage of these capabilities. The interface is designed for use on a Linux cluster, providing very high throughput. It can also be used on a single computer. Among the features it gives access to are basic calculations (Twiss parameters, radiation integrals), phase-space tracking, nonlinear dispersion, dynamic aperture (on- and off-momentum), frequency map analysis, and collective effects (IBS, bunch-lengthening). Using a cluster, it is easy to get highly detailed dynamic aperture and frequency map results in a surprisingly short time.

• H. Shang, M. Borland
  ANL, Argonne, Illinois

Optimization is commonly used in accelerator design to find linear optics solutions. Such optimizations are usually fairly fast as linear optics computations are themselves fast. For high-brightness storage rings, optimization of nonlinear elements (e.g., sextupoles) is also important in obtaining sufficient dynamic aperture. However, this can be very time onsuming as the basic calculations are time consuming. We have developed an efficient parallel Simplex optimizer that runs on a Linux cluster. It can optimize the result of running essentially any program or script that returns a penalty function value. We have used this optimizer with elegant to optimize dynamic aperture of storage ring designs. We discuss the optimization algorithm and performance, design of penalty functions, and optimization results.

• H. Okamoto
  HU/AdSM, Higashi-Hiroshima