Longitudinal beam dynamic simulation of CTF3 (CL

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Longitudinal beam dynamic simulation of CTF3 (CL
CT) with MathCAD ,Placet and Parmila and an
initial bunch length measurement
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Comparison between MathCAD, Placet and Parmila
1- The base program is MathCAD and focus on
Longitudinal simulation and at the moment
contains Wakefield effect and no space charge
effect. 2- Parmila was used by Peter Urschütz to
calculate beam after Injector(point A) and after
girder 3(point B) and after first chicane(point
C) and contains space charge effect and no
Wakefield effect. 3- Placet model that Andrea
Latina gave me starts from point C and was used
for point D and E and contains Wakefield effect
and no space charge effect.
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Point A (after Injector) with Parmila
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Point B with Parmila and MathCAD (without
Wakefield effect)
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Point C(after chicane) with Parmila and
MathCAD(without Wakefield effect)
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Point C with MathCAD with and without Wakefield
effect
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Point D(after Girder 15) with MathCAD and Placet
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Point D with MathCAD with and without Wakefield
effect
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Point E with MathCAD with and without phase
changing of Girder 15
We changed the phase of Girder 15 by
20. R560.45 here
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Bunch length calculation per phase of Girder 15
in point E with MathCAD
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Non-linearity between c?t and ?P/P and transverse
correlation in Placet model
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Calibration of device RF Deflector
Chicane optics bunch length measurements - 2004
13/25
A. Dabrowski, 17 October 2007
CTF3 Technical meeting
Bunch length monitoring
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Measurement RF deflector 2007
Measurement method( scan method)
Change the 1.5 GHz RF deflector phase and measure
the average intensity of a thin band on the
middle of screen per each phase. The phase of RFD
related to bunch length by c/f factor. (c is
speed of light and f1.5 GHz)
Standard deviation c/f 2.84 0.35 mm
Slide H. Shaker
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Measurement RF deflector 2006-2007
Single Image method 1) Measure the bunch
length in monitor in pixel units for a single
image 2) Calibrate the monitor by finding the
equivalence between pixel unit and length unit
(mm) by measuring the relationship between the
center of the image position per RF deflector
phase Advantage Scan method vs. Single Image
method ?Avoid non-linearity effects from the
screen ?Image can be bigger than the screen
(improved resolution) Disadvantage ?Need to
assume bunch shape remains constant during the
scan
Example of Calibration curve for Single Image
method ref. D.Alesini et al CTFF3-010 INFN
Slide H. Shaker
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Measurement RF deflector 2007
May 2007 Bunch length 2.45 0.28 mm Phase of
MKS constant for 7 measurements, Scan method
used
Bunch Length (mm)
December 2007 Example Bunch length _at_ 240
degrees MKS13 2.75 0.27 mm
Bunch Length (mm)
Klystron 13 Phase (degree)
Slide H. Shaker