Author: Zobov, M.
Paper Title Page
MOXAT0102
The DAΦNE Legacy to Future Colliders  
 
  • M. Zobov
    LNF-INFN, Frascati, Italy
 
  25 years ago the first beam was stored in the DAΦNE electron-positron collider working at the energy of Phi resonance (1.02 GeV c.m.). Since then much efforts have been dedicated to obtain the luminosity substantially higher than that ever achieved at the colliders operated in this energy range and to provide data for several experimental detectors aimed at studying the high energy and nuclear physics. Careful beam optics modeling and nonlinear dynamics studies, design of the low impedance vacuum chamber, suppression of a variety of beam instabilities and investigation of beam-beam interaction have helped to reach the impressive result. Several novel ideas in the accelerator physics have been proposed and/or tested at DAΦNE for the first time. In particular, the Crab waist concept originally proposed and then tested at Frascati has been already successfully applied in SuperKEKB and now it is considered for implementation in the future electron-positron factories. In this paper we discuss the relevant advanced accelerator studies performed at DAΦNE which can be also of some interest to other circular colliders.  
slides icon Slides MOXAT0102 [7.467 MB]  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEXAT0104
Beam-beam Simulations including Coupling Impedance  
 
  • Y. Zhang, N. Wang
    IHEP, Beijing, People’s Republic of China
  • M. Migliorati
    Sapienza University of Rome, Rome, Italy
  • K. Ohmi, D. Zhou
    KEK, Ibaraki, Japan
  • M. Zobov
    LNF-INFN, Frascati, Italy
 
  The design performance of future e+e ring colliders has been pushed to new extreme based on the crab-waist scheme. The new found coherent head-tail instability (X-Z instability) may induce the horizontal beam size blowup and reduce the machine performance. The longitudinal coupling impedance would distort the phase space: lengthen the bunch and bring incoherent synchrotron tune spread. The simulation study has found the clear influence of longitudinal impedance on the X-Z instability in both CEPC and FCCee. With the evolvement of future machine design process, the transverse impedance has also been included. The results show that a vertical beam-beam TMCI-like instability may be induced when the impedance is considered. It is first found in e+e colliders. Some similar study at SuperKEKB will also be presented. It could be expected or concluded that different effect would couple and determine the final performance together in present and future high performance crab-waist colliders. Separate effect study seems not enough to evaluate and predict the machine performance/stability.  
slides icon Slides WEXAT0104 [3.976 MB]  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEYAT0104
Collective Effects Studies in FCC-ee  
 
  • E. Carideo
    CERN, Meyrin, Switzerland
  • M. Behtouei, B. Spataro, M. Zobov
    LNF-INFN, Frascati, Italy
  • M. Migliorati
    INFN-Roma1, Rome, Italy
 
  The high luminosity foreseen in the future electron-positron circular collider (FCC-ee) necessitates very intense multi-bunch colliding beams with very small transverse beam sizes at the collision points. This requires emittances comparable to those of the modern synchrotron light sources. At the same time, the stored beam currents should be close to the best values achieved in the last generation of particle factories. This combination of opposite factors represents a big challenge in order to preserve a high beam quality avoiding, at the same time, a machine performance degradation. As a consequence, a careful study of the collective effects and some solutions for the mitigation of foreseen instabilities is required. In this contribution we discuss the current status of these studies.  
slides icon Slides WEYAT0104 [15.810 MB]  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)