Abstracts Brochure - CERN

WEPCH150
WEPCH151
WEPCH152
28-Jun-06 16:00 - 18:00 WEPCH — Poster Session
it is often a very tedious exercise to compare results from the two types of codes in any great detail. As described in
a companion paper in these proceedings, differences in the choice of phase space variables, as well as the inherent
differences between the Lie algebraic and matrix formulations, make for unwieldy and complex relations between
results from the two types of codes. Computational capabilities have been added to the PBO Lab software that
automates the calculation of transfer matrices from Lie maps, and that converts phase space distributions between
the different representations used by the codes considered here. Graphical and quantitative comparison tools have
been developed for quick and easy visual comparisons of transfer maps and matrices.
Accelerator Markup Language
D. Sagan, M. Forster (Cornell University, Laboratory for Elementary-Particle
Physics) D.A. Bates, A. Wolski (LBNL) T. Larrieu, Y.
Roblin (Jefferson Lab) T.A. Pelaia (ORNL) S. Reiche (UCLA) F.
Schmidt (CERN) P. Tenenbaum, M. Woodley (SLAC) N.J. Walker
(DESY) R.M. Zwaska (The University of Texas at Austin)
316
A major problem in accelerator physics has
been the sharing of lattice description files
between programs. At present, there is no
generally accepted lattice format that is comprehensive
enough to meet current needs. To
alleviate this problem, a lattice description
format called Accelerator Markup Language
(AML) has been created. AML is based upon the standard Extensible Markup Language (XML) format which gives
AML the needed flexibility to be easily extended to changing requirements. In conjunction with AML, A set of parsing
routines is being developed to speed the integration of AML into any program. These routines, collectively known as
the Universal Accelerator Parser (UAP), will have the added feature of being able to translate MAD compatible lattice
files and will also contain the needed hooks so that it will be a relatively simple matter to extend UAP to accommodate
other lattice formats. Back parser routines to create AML and MAD lattice files will also be part of the UAP package.
A Study of Nonlinear Effects and Correction in Colliders
High-order models of the 50-GeV Muon Col-
C. Johnstone (Fermilab)
lider and the ILC have been developed using
the code COSY. Studies using these models
have been performed of the significant nonlinearities and the impact of correction schemes. In particular the dynamic
aperture dependence of the Muon Collider was studied and corrected and the dependence of spot size aberrations in
the ILC.
Comment on Healy’s Symplectification Algorithm
For long-term tracking, it is important to have
W.W. MacKay (BNL)
symplectic maps for the various electromagnetic
elements in an accelerator ring. While
many standard elements are handled well by modern tracking programs, new magnet configurations (e.g., a helical
dipole with a superimposed solenoid) are being used in real accelerators. Transport matrices and higher terms may
be calculated by numerical integration through model-generated or measured field maps. The resulting matrices are
most likely not quite symplectic due to numerical errors in the integrators as well as the field maps. In his thesis*,
Healy presented a simple algorithm to symplectify a matrix. This paper presents a discussion of limitations of this
method.