Paper |
Title |
Page |
TUPC019 |
A Retarding Field Detector to Measure the Actual Energy of Electrons Participating in E-cloud Formation in Accelerators
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1086 |
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- R. Cimino, M. Commisso, T. Demma, S. Guiducci, P. Liu, A. R. Raco, V. Tullio, G. Viviani
INFN/LNF, Frascati (Roma)
- P. Vilmercati
ELETTRA, Basovizza, Trieste
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Electron cloud related phenomena can cause potentially detrimental effects on beam stability in many planned and under construction accelerators. The possibility to reduce such unwanted phenomena lies on the observation that, machine commissioning does reduce Secondary Electron Yield (SEY). Such SEY reduction (scrubbing) is due to the fact that electrons produced during e-cloud formation hit the accelerator wall, modifying their surface properties. Scrubbing has been studied only as a function of impinging electron dose but never as a function of the e-cloud electron energy. Simulations predict that the e-cloud is formed by electrons with very low energies (<50 eV). Given the potentially lower scrubbing efficiency for equal dose of very low energy electrons compared to medium energy one, it would be important to measure the actual energy of the electrons forming the cloud in real accelerators. For this reason we decided to construct an optimized retarding Field energy electrometer to be installed in accelerators. Here we will describe what solutions have been adopted during the design phase of such home made detector and some laboratory test will be showed and discussed.
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TUPP031 |
Electron Cloud Simulations for DAΦNE
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1604 |
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- T. Demma, R. Cimino, S. Guiducci, C. Vaccarezza, M. Zobov
INFN/LNF, Frascati (Roma)
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After the first experimental observations compatible with the presence of the electron cloud effect in the DAΦNE positron ring, a systematic study has been performed regarding the electron cloud build-up. To assess the effects of the electron cloud, simulations of the cloud build up were carried out using ECLOUD. In particular, we discuss modifications to the secondary emission model, build up for various filling patterns and different wiggler magnetic field models. The obtained numerical results are compared with experimental observations.
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WEPP039 |
Design of a 1036 cm-2 s-1 Super-B Factory
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2605 |
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- J. Seeman, K. J. Bertsche, A. Novokhatski, M. K. Sullivan, U. Wienands, W. Wittmer
SLAC, Menlo Park, California
- S. Bettoni
CERN, Geneva
- M. E. Biagini, R. Boni, M. Boscolo, T. Demma, A. Drago, S. Guiducci, P. Raimondi, S. Tomassini, M. Zobov
INFN/LNF, Frascati (Roma)
- A. Bogomyagkov, I. Koop, E. B. Levichev, S. A. Nikitin, P. A. Piminov, D. N. Shatilov
BINP SB RAS, Novosibirsk
- G. Marchiori
INFN-Pisa, Pisa
- E. Paoloni
University of Pisa and INFN, Pisa
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Submitted for the High Luminosity Study Group for an Asymmetric Super-B-Factory: Parameters are being studied for a high luminosity e+e- collider operating at the Upsilon 4S that would deliver a luminosity of 1 to 2 x 1036/cm2/s. This collider would use a novel combination of linear collider and storage ring techniques. In this scheme an electron beam and a positron beam are stored in low-emittance damping rings similar to those designed for a Linear Collider (LC) or the next generation light source. A LC style interaction region is included in the ring to produce sub-millimeter vertical beta functions at the collision point. A large crossing angle (±25 mrad) is used at the collision point to allow beam separation. A crab-waist scheme is used to reduce the hourglass effect and restore peak luminosity. Beam currents of about 1.8 A in 1400 bunches can produce a luminosity of 1036/cm2/s with upgrade possibilities. Design parameters and beam dynamics effects are discussed.
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WEXG02 |
Crabbed Waist Collisions in DAΦNE and Super-B Design
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1898 |
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- P. Raimondi, D. Alesini, M. E. Biagini, C. Biscari, R. Boni, M. Boscolo, F. Bossi, B. Buonomo, A. Clozza, G. O. Delle Monache, T. Demma, E. Di Pasquale, G. Di Pirro, A. Drago, A. Gallo, A. Ghigo, S. Guiducci, C. Ligi, F. Marcellini, G. Mazzitelli, C. Milardi, F. Murtas, L. Pellegrino, M. A. Preger, L. Quintieri, R. Ricci, U. Rotundo, C. Sanelli, M. Serio, F. Sgamma, B. Spataro, A. Stecchi, A. Stella, S. Tomassini, C. Vaccarezza, M. Zobov
INFN/LNF, Frascati (Roma)
- N. Arnaud, D. Breton, P. Roudeau, A. Stocchi, V. Variola, B. F. Viaud
LAL, Orsay
- S. Bettoni
CERN, Geneva
- P. Branchini
roma3, Rome
- M. Esposito
Rome University La Sapienza, Roma
- I. Koop, E. B. Levichev, P. A. Piminov, D. N. Shatilov, V. V. Smaluk
BINP SB RAS, Novosibirsk
- K. Ohmi
KEK, Ibaraki
- E. Paoloni
University of Pisa and INFN, Pisa
- M. Schioppa
INFN Gruppo di Cosenza, Arcavacata di Rende (Cosenza)
- D. Teytelman
SLAC, Menlo Park, California
- P. Valente
INFN-Roma, Roma
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The new idea of increasing the luminosity of a collider with crabbed waist collisions and first experimental results from DAΦNE using this concept are presented. Consequences for the design of future factories will be discussed. An outlook to the performance reach with crabbed waist collisions is given, with emphasis on future B Factories.
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Slides
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WEPP036 |
DAΦNE Setup and Operation with the Crab-Waist Collision Scheme
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2599 |
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- C. Milardi, D. Alesini, M. E. Biagini, C. Biscari, R. Boni, M. Boscolo, F. Bossi, B. Buonomo, A. Clozza, G. O. Delle Monache, T. Demma, E. Di Pasquale, G. Di Pirro, A. Drago, A. Gallo, A. Ghigo, S. Guiducci, C. Ligi, F. Marcellini, G. Mazzitelli, F. Murtas, L. Pellegrino, M. A. Preger, L. Quintieri, P. Raimondi, R. Ricci, U. Rotundo, C. Sanelli, M. Serio, F. Sgamma, B. Spataro, A. Stecchi, A. Stella, S. Tomassini, C. Vaccarezza, M. Zobov
INFN/LNF, Frascati (Roma)
- N. Arnaud, D. Breton, P. Roudeau, A. Stocchi, V. Variola, B. F. Viaud
LAL, Orsay
- S. Bettoni
CERN, Geneva
- P. Branchini
roma3, Rome
- M. Esposito
Rome University La Sapienza, Roma
- I. Koop, E. B. Levichev, P. A. Piminov, D. N. Shatilov
BINP SB RAS, Novosibirsk
- K. Ohmi
KEK, Ibaraki
- E. Paoloni
University of Pisa and INFN, Pisa
- M. Schioppa
INFN Gruppo di Cosenza, Arcavacata di Rende (Cosenza)
- V. V. Smaluk
BINP, Novosibirsk
- P. Valente
INFN-Roma, Roma
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In the second half of 2007 a major upgrade has been implemented on the Frascati DAΦNE collider in order to test the novel idea of Crab Waist collisions. New vacuum chambers and permanent quadrupole magnets have been designed, fabricated and installed to realize the new configuration. At the same time the performances of relevant hardware components, such as fast injection kickers and shielded bellows have been improved relying on new design concepts. The collider has been successfully commissioned in this new configuration. The paper describes the new layout as well as several experimental results about linear and non-linear optics setup and optimization, damping of beam instabilities and discusses the obtained luminosity performances.
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