TREDI test for CSR

TREDI test forCSR

L. Giannessi – M. Quattromini

Presented at

TREDI : SELF FIELDS & Retarded Potentials

EnB

Rn

n

Rn

nnE

ret

23

2

31

1

1

c

tRtt

R

Rn

)( timeRetarded

R(t’)Target

Source

Trajectories are stored and the fields evaluation requires bracketing of the retarded condition.

• Cpu – memory consuming• Non trivial field reglarization by grid assignement (Parmela mode)• “extended particles” requires careful treatment of ret. condition

TREDI Features

• 15000 lines in C language;

• Scalar & Parallel (MPI 2.0);

• Unix & Windows versions;

• Tcl/Tk Gui (pre-processing);

• Mathematica & MathCad frontends (post-processing);

• Output format in NCSA HDF5 format (solve endian-ness/alignement problems)

Conclusions of Zehuten workshop

• The noise suppression method has reduced the effects of SF on longitudinal phase space, without being completely effective in the transverse phase space

• A rigorous model of fields regularization, relying on a realistic momentum dispersion of macroparticles will be soon implemented

• The low number of macroparticles in severely limiting the reliability of the results

• Diagnostic on fields will be implemented to improve insight on the smoothing procedure

• The reason of the slow down of the code must be understood

• Before the end of the workshop the 1000 particles case will be finished - we will see.

Effect of Noise (1st bend - no screening)

six months after Zehuten, Chia Laguna… Introduced radiative energy loss (ISR)

Now use HDF5 data format support to fix endianess/alignmentsproblems (output portability to different platforms)

?? Improved acceleration fields smothness (more work required, no manifestly covariant, CPU consuming)

Fields blow up when we have collinear divergencies –

Solution: target macro particles are given a finite extension in space

Big speed up (improved retarded time condition routine):

six months ago: very few particles (300 particles 4h on an IBM SP3/16 nodes - 400 MHz each)

Now: 1000 particles 35m on an equivalent platform10000 particles in 27h on a 32CPUs platform

improvements and bug fixes; recently introduced a “Parmela-like” mode (instantaneous interactions,MUCH faster still experimental)

In Zehuten: Phase space at exit still noisy !Definitions

2 1.5 1 0.5 0 0.52

1

0

1

2X Projection

X (mm)

Px

(mc)

0.1 0.05 0 0.05 0.10.2

0.1

0

0.1

0.2Y Projection

Y (mm)

Py

(mc)

Step s 94Z 15.881

Angle 1.819 105

Optic functionsx 0.724

x 6.403

x 0.238

y 1.099

y 15.131

y 0.146

z 2.406

z 7.384 103

z 919.209

0.08 0.06 0.04 0.02 0 0.02 0.04 0.06400

200

0

200Z Projection

Z (mm)

Pz

(mc)

0 5 10 150

0.1

0.2

X - Z Trajectory

Z (m)

X (

mm

)

After changes to field regularization

0 10 20 30 40 50 60 70 80 90 1000

1

2

3

Charge (%)

Em

ittan

ce/(

% C

harg

e)

.

0 10 20 30 40 50 60 70 80 90 1001

10

100

Charge (%)

Emitt

ance

/(% C

harg

e)

85

.

0 10 20 30 40 50 60 70 80 90 1001

10

100

Charge (%)

Emitt

ance

/(% C

harg

e)

85

.

Ex=1.8 mm-mrad

Ex=2.3 mm-mrad

5 GeV – 1 nC Gaussian

0.15 0.09 0.03 0 0.09 0.150.3

0.18

0.05

0

X Projection

X (mm)

Px

(mc)

0.15 0.09 0.03 0 0.09 0.150.2

0.1

0

0.1

0.2Y Projection

Y (mm)

Py

(mc)

Step k s( ) 1914Z 16.001

Angle 5.711 107


x 8.328

x 0.228

y 1.255

y 17.635

y 0.146

z 7.76

z 0.022

z 2.753 103

x 1.844 104 mm mrad

y 9.812 105 mm mrad

z 0.019mm mrad

0.08 0.06 0.04 0.02 0 0.02 0.04200

100

0

100

200

300Z Projection

Z (mm)

Pz

(mc)

0 5.33 10.67 160

0.15

0.3X - Z Trajectory

Z (m)

X (

mm

)

View Phase Space

5 GeV – 1 nC Gaussian

0 2 4 6 8 10 12 14 16 180

5 105

1 104

1.5 104

2 104

time*c (m)

Z R

MS

(m

)

0 2 4 6 8 10 12 14 16 180

5 104

0.001

0.0015

0.002

time*c (m)

X R

MS

(m

)

0 2 4 6 8 10 12 14 16 180.02

0.015

0.01

0.005

0

time*c (m)

Ene

rgy

chan

ge (

%)

0 2 4 6 8 10 12 14 16 180.7165

0.717

0.7175

0.718

0.7185

time*c (m)

Ene

rgy

Spr

ead

(%)

5 GeV - 1 nC Gaussian

60 40 20 0 20 40 600

1

2

3

4

XYZ

Slice Emittance

Z (um)

Em

ittan

ce (

mm

-mra

d)

60 40 20 0 20 40 600

2

4

6

8Current vs longitudinal coordinate

Z (um)

I (K

A)

60 40 20 0 20 40 600

0.075

0.15Slice Energy Spread

Z (um)

Ene

rgy

spre

ad (

%)

60 40 20 0 20 40 600.025

0.02

0.015

0.01

0.005

0

mean energy variation (%)

Energy variation from beam 0

Z (um)

5 GeV – 0.5 nC Gaussian

0 2 4 6 8 10 12 14 16 180

5 105

1 104

1.5 104

2 104

time*c (m)

Z R

MS

(m

)

0 2 4 6 8 10 12 14 16 180

5 104

0.001

0.0015

0.002

time*c (m)

X R

MS

(m

)

0 2 4 6 8 10 12 14 16 180.015

0.01

0.005

0

time*c (m)

Ene

rgy

chan

ge (

%)

0 2 4 6 8 10 12 14 16 180.7174

0.7176

0.7178

0.718

0.7182

0.7184

time*c (m)

Ene

rgy

Spr

ead

(%)


0.1 0.05 0 0.05 0.10.2

0.1

0

0.1

0.2X Projection

X (mm)

Px

(mc)

0.15 0.09 0.03 0 0.09 0.150.2

0.1

0

0.1

0.2Y Projection

Y (mm)

Py

(mc)

Step k s( ) 1927Z 16

Angle 5.822 107


x 7.076

x 0.193

y 1.307

y 17.884

y 0.151

z 7.818

z 0.022

z 2.773 103

x 1.312 104

mm mrad

y 9.816 105

mm mrad

z 0.018mm mrad

0.08 0.06 0.04 0.02 0 0.02 0.04 0.06200

100

0

100

200

300Z Projection

Z (mm)

Pz

(mc)

0 5.33 10.67 160

0.15

0.3X - Z Trajectory

Z (m)

X (

mm

)

View Phase Space


60 40 20 0 20 40 600

0.5

1

1.5

2

2.5

XYZ

Slice Emittance

Z (um)

Em

ittan

ce (

mm

-mra

d)

60 40 20 0 20 40 600

1

2

3


Z (um)

I (K

A)

60 40 20 0 20 40 600

0.075


Z (um)

Ene

rgy

spre

ad (

%)

60 40 20 0 20 40 600.015

0.01

0.005

0



Z (um)

5 GeV – 1.0 nC Uniform

0.15 0.09 0.03 0 0.09 0.150.4

0.2

0

0.2

0.4X Projection

X (mm)

Px

(mc)

0.15 0.09 0.03 0 0.09 0.150.2

0.1

0

0.1

0.2Y Projection

Y (mm)

Py

(mc)

Step k s( ) 1935Z 16.001

Angle 3.95 108


x 8.156

x 0.234

y 1.248

y 17.524

y 0.146

z 11.448

z 0.032

z 4.102 103

x 1.824 104 mm mrad

y 9.789 105 mm mrad

z 0.013mm mrad

0.04 0.02 0 0.02 0.04200

100

0

100

200Z Projection

Z (mm)

Pz

(mc)

0 5.33 10.67 160

0.15

0.3X - Z Trajectory

Z (m)

X (

mm

)

View Phase Space


0 2 4 6 8 10 12 14 16 180

5 105

1 104

1.5 104

2 104

time*c (m)

Z R

MS

(m

)

0 2 4 6 8 10 12 14 16 180

5 104

0.001

0.0015

0.002

time*c (m)

X R

MS

(m

)

0 2 4 6 8 10 12 14 16 180.02

0.015

0.01

0.005

0

time*c (m)

Ene

rgy

chan

ge (

%)

0 2 4 6 8 10 12 14 16 180.718

0.7185

0.719

0.7195

0.72

time*c (m)

Ene

rgy

Spr

ead

(%)


40 20 0 20 400

0.5

1

1.5

2

2.5

XYZ

Slice Emittance

Z (um)

Em

ittan

ce (

mm

-mra

d)

40 20 0 20 400

2

4

6


Z (um)

I (K

A)

40 20 0 20 400

0.02

0.04

0.06


Z (um)

Ene

rgy

spre

ad (

%)

40 20 0 20 400.02

0.015

0.01



Z (um)

500 MeV 1.0nC Gaussian

1 0.5 0 0.5 10.2

0.1

0

0.1

0.2X Projection

X (mm)

Px

(mc)

0.4 0.2 0 0.2 0.40.04

0.02

0

0.02

0.04Y Projection

Y (mm)

Py

(mc)

Step k s( ) 1908Z 16.001

Angle 4.071 106


x 8.576

x 0.243

y 0.694

y 13.95

y 0.106

z 4.087

z 0.013

z 1.399 103

x 6.781 103 mm mrad

y 1.058 103 mm mrad

z 0.035mm mrad

0.08 0.06 0.04 0.02 0 0.02 0.0420

10

0

10

20

30Z Projection

Z (mm)

Pz

(mc)

0 5.33 10.67 160

0.15

0.3X - Z Trajectory

Z (m)

X (

mm

)

View Phase Space


0 2 4 6 8 10 12 14 16 180

5 105

1 104

1.5 104

2 104

time*c (m)

Z R

MS

(m

)

0 2 4 6 8 10 12 14 16 180

5 104

0.001

0.0015

0.002

time*c (m)

X R

MS

(m

)

0 2 4 6 8 10 12 14 16 180.15

0.083

0.017

0

time*c (m)

Ene

rgy

chan

ge (

%)

0 2 4 6 8 10 12 14 16 180.69

0.7

0.71

0.72

time*c (m)

Ene

rgy

Spr

ead

(%)


60 40 20 0 20 40 600

2

4

6

8

XYZ

Slice Emittance

Z (um)

Em

ittan

ce (

mm

-mra

d)

60 40 20 0 20 40 600

2

4

6


Z (um)

I (K

A)

60 40 20 0 20 40 600

0.15


Z (um)

Ene

rgy

spre

ad (

%)

60 40 20 0 20 40 600.2

0.15

0.1

0.05

0



Z (um)

ICFA Beam Dynamics mini workshopCoherent Synchrotron Radiation and its impact on

the dynamics of high brightness electron beamsJanuary 14-18, 2002 at DESY-Zeuthen (Berlin, GERMANY)

http://www.desy.de/csr

3D E E

3D TRAFIC4 -0.058 -0.002 1.4

TREDI* -0.041 0.017 2.3

2D Program by R.LI -0.056 -0.006 1.32

1D Elegant -0.045 -0.0043 1.55

CSR_CALC -0.043 -0.004 1.52

Program by M. Dohlus -0.045 -0.011 1.62

* 15% cut of charge to reduce noise

-0.018 -0.001 1.85

Conclusions

• The agreement with other codes is improved with the new macroparticles model

• The cpu time is greatly reduced, this allows to run a larger number of macroparticles, but not yet sufficient to simulate microbunching.

• Fields regularization requires more work (still time consuming, not covariant)

• The code provides reasonable results in a wide range of conditions … start to FEL simulations ?

TREDI test for CSR

Documents

Transcript of TREDI test for CSR