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Movement analysis

This operation finds closed orbits and analyses both stable and unstable motions for up to 15 different momenta.
NOTE: no kicks simulating synchrotron oscillation (gkick parameter T $<$ 0 ) may exist in the lattice. Results are meaningless in the presence of such kicks.

Input Format 

MOVEment analysis ..... (up to 80 char)
nprint nturn nanal nit nener ncoef dist
x x' y y' l $\delta_{1} \dots \delta_{{\rm nener}}$
naplt delmin delmax dnumin dnumax dbmin dbmax ncol nline
Parameter definitions

nprint $\textstyle \parbox{10cm}{ print action for the
closed orbit information}$

0 $\textstyle \parbox{10cm}{ action after every element}$

n $\textstyle \parbox{10cm}{ action after every n turn}$

nturn $\textstyle \parbox{10cm}{ number of turns over
which analysis is performed. It
enables user to study higher order resonances.}$

nanal

0 $\textstyle \parbox{10cm}{ no stability analysis is done,
only the closed orbit is
computed.}$

1 $\textstyle \parbox{10cm}{ stability analysis is
performed (both stable and
unstable).}$

2 $\textstyle \parbox{10cm}{ gives information about an
order two resonance. (nturn
must then be equal to 2.)}$

3 $\textstyle \parbox{10cm}{ gives information about
an order three resonance.
(nturn must then be equal to 3.)}$

NOTE: in both cases where NANAL is equal to 2 or 3 the resonance motion analyzed is supposed to occur in the horizontal phase plane. If the user wants to study resonance in the vertical plane, the machine should be set up so that its planes are exchanged. In the versions subsequent to April 1 1988, the coordinates of the particles close to the unstable fixed point of the first momentum are stored for subsequent use in a tracking operation. See the demo3 input file for its use

nit $\textstyle \parbox{10cm}{ number of iterations
used. ABS(nit) iterations are
...
...ormed. If nit is negative only the results of the
last iteration are printed.}$

nener $\textstyle \parbox{10cm}{ number of momenta for
which the analysis is performed.
(max 15)}$

ncoef $\textstyle \parbox{10cm}{ number of coefficients
to be used in the Taylor
ex...
... fixed at 0.01(1momentum can be changed by the CONStant definition
operation.}$

dist $\textstyle \parbox{10cm}{ indicates the 'distance'
(in phase space) from the
...
...e lower value
depending on the size of the phase space occupied by
the beam.}$

x,x',y,y',l $\textstyle \parbox{10cm}{estimate of the coordinates of the
closed orbit.}$

$\delta_{i}$ $\textstyle \parbox{10cm}{ Momenta(dp/p) for which
the analysis is
performed. i = 1 to nener}$

naplt

0 $\textstyle \parbox{10cm}{ no plot of the Taylor expansion
is required}$

1 $\textstyle \parbox{10cm}{ a plot is required}$

delmin delmax $\textstyle \parbox{10cm}{ min max of dp/p
for the plot.}$

dnumin dnumax $\textstyle \parbox{10cm}{ min max for dnu
(the first momentum serves as the
reference to compute the tune difference dnu).}$

dbmin dbmax $\textstyle \parbox{10cm}{ min max for relative
difference in betas.}$

ncol nline $\textstyle \parbox{10cm}{ number of columns and
lines desired for plot.}$



Examples

The first example comes from demo2 where it is used to analyse the momentum dependence of the parameters of a stable motion.

The second, taken from demo3, illustrates the study of a third order resonance, and the use of a subsequent tracking operation to obtain the separatrices associated to the third order resonance.

MOVEMENT ANALYSIS (CHROMATIC EXPANSION) NO GRAPH
1 1 1 -4 15 6 0.00001
0 0 0 0 0
0.0 -.00001 0.00001 -.00003 0.00003
-.0001 0.0001 -.0003 0.0003 -.001 0.001
-.003 0.003 -.006 0.006
0,

MOVEMENT ANALYSIS TO FIND UNSTABLE CLOSED ORBIT NEAR .03 .002 0 0
1 3 3 -4 1 0 .00001 0.03 0.002 0.0 0.0 0.0 0.00 0,
tracking the 10 particles generated by the movemenet analysis just above
1 -2 0 1600
0
11
-.010 0.010 -.002 0.002
-.0006 0.0006 .0003 0.0003
51 51,


next up previous
Next: Output control Up: Use and description of Previous: Modification of element data
Dobrin Kaltchev 2004-10-20