Paper  Title  Page 

TUOCAB01  A New Code for Orbit Response Matrix Analysis  804 


Funding: NSF PHY0552389, DOE DEFG0292ER40747 The Orbit Response Matrix (ORM) has been successfully used extensively in accelerator modeling. However, in many cases, the existing codes can not find a correct model. We develop a new code that solve the convergence and coupling problems. We test our code by carrying out systematic study of accelerator models. Effects measurement errors and the completeness of information will be addressed in this study. Possible inclusion of phase information will be discussed. 

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TUPMS007  NSLS VUV Ring Lifetime Study  1203 


Beam lifetime at VUV ring of National Synchrotron Light Source(NSLS) at BNL is limited by Touschek effect. This effect is affected by momentum acceptance and beam density. The geometry near injection septum, dynamic aperture and the RF acceptance all can limit the over all momentum acceptance. Extensive experiments including coupling, gas scattering, RF acceptance, have been done for understanding the lifetime, and the result is confirmed with theoretical predictions.  
TUPMS074  Collective Effects in the NSLSII Storage Ring  1344 


Funding: This work was supported by Department of Energy contract DEAC0298CH10886. A new highbrightness synchrotron light source (NSLSII) is under design at BNL. The 3GeV NSLSII storage ring has a doublebend achromatic lattice with damping wigglers installed in zerodispersion straights to reduce the emittance below 1nm. In this note, we present an overview of the impact of collective effects upon the performance of the storage ring. Subjects discussed include Touschek lifetime, intrabeam scattering, instability thresholds due to ring impedance, and use of a thirdharmonic Landau cavity. 

TUPMS078  IBS Effects in a Wiggler Dominated Light Source  1353 


Intrabeam scattering (IBS) is often thought of as a fundamental limitation to achieving lower emittance and hence higher brightness in modern storage ring light sources. However, as we show in this paper analytically and by simulations using SAD code, this limitation may no longer be relevant in a wiggler dominated 3rd generation light source. Instead, lowering the emittance by increasing the amount of wiggler radiation does not result in significant IBS induced emittance blowup, as higher beam density (and IBS rates) is compensated by faster radiation damping. We show that under some practical assumptions the relative ratio of the emittance including the IBS effect to the emittance at zero current is emittance independent.  
WEOAC04  Impedance Minimization by Nonlinear Tapering  2006 


There exist analytical approximations that express the transverse geometric impedance of tapered transitions in the inductive regime as a functional of the transition boundary and its derivatives. Assuming the initial and final crosssections and the transition length are fixed, one can minimize these functionals by appropriate choice of the boundary variation with the longitudinal coordinate. In this paper we numerically investigate how well this works for the cases of optimized tapered transitions in circular, elliptical and rectangular geometry by running ABCI, ECHO, and GDFIDL EM field solvers. We show that a significant reduction of impedance for optimized boundary compared to that of a linear taper is indeed possible in some cases, and then we compare this reduction to analytical predictions.  
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