x-band based injector layout: s2e modelling€¦ · 3d design •3d tracking with space charge for...

X-Band Based Injector Layout: S2E modelling

[email protected]

Oct 2nd, Geneva, 2019

mailto:[email protected]

Outline

• Overview of the facility layout and LINAC module

• At Mid-term Review Meeting 2019

• Further 1D simulation design study with more linearizer options

• 3D simulation study by A. Aksoy

• Summary and coming work

3

Baseline and module layout for two modes (HX@100 Hz & SX@1 kHz)https://espace.cern.ch/compactlight/_layouts/15/start.aspx#/XLS%20wiki/

Low Energy LINAC Section High Energy LINAC Section

https://espace.cern.ch/compactlight/XLS%20wiki/RF-module.aspx

https://espace.cern.ch/compactlight/_layouts/15/start.aspx#/XLS%20wiki/

https://espace.cern.ch/compactlight/XLS%20wiki/RF-module.aspx

At 2019 Mid-term Review (Helsinki)1D X+K scheme at HX mode 1D stability and tolerance study

*X. Liu, Mid-term Review Meeting, Jul 3, 2019https://indico.cern.ch/event/804400/contributions/3484991/

https://indico.cern.ch/event/804400/contributions/3484991/

More linearizer options!S-Band Acc

3 GHz, N? Cell 15 MV/m

X-Band Lnz12 GHz, N? Cell

G MV/m

Undulatorlu ,K,

N? section

1S-Band gun

3 GHz, 1.6? Cell 100 MV?

BC1Chicane

X-Band Acc12 GHz, N? Cell

G MV/m

BC2Chicane


G MV/m

2C-Band gun

6 GHz, 3.6? Cell 200 MV?

C-Band Acc6 GHz, N? Cell

G MV/m


G MV/m

BC1Chicane


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m

3X-Band gun12 GHz, 5.6? Cell

300 MV?

BC1Dogleg


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


G MV/m


300 MV?

BC1Chicane


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


G MV/m

K-Band lnz36 GHz, N? Cell

G MV/m

InjectorDesign Linac Design

Undulator Design

S2E modeling

S-Band Acc3 GHz, N? Cell

15 MV/m


G MV/m

Undulatorlu ,K,

N? section

1S-Band gun

3 GHz, 1.6? Cell 100 MV?

BC1Chicane


G MV/m

BC2Chicane


G MV/m

2C-Band gun

6 GHz, 3.6? Cell 200 MV?


G MV/m


G MV/m

BC1Chicane


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


300 MV?

BC1Dogleg


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


G MV/m


300 MV?

BC1Chicane


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


G MV/m


G MV/m

V-Band lnz48GHz


15 MV/m


G MV/m

Undulatorlu ,K,

N? section

1S-Band gun

3 GHz, 1.6? Cell 100 MV?

BC1Chicane


G MV/m

BC2Chicane


G MV/m

2C-Band gun

6 GHz, 3.6? Cell 200 MV?


G MV/m


G MV/m

BC1Chicane


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


300 MV?

BC1Dogleg


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


G MV/m


300 MV?

BC1Chicane


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


G MV/m


G MV/m


15 MV/m


G MV/m

Undulatorlu ,K,

N? section

1S-Band gun

3 GHz, 1.6? Cell 100 MV?

BC1Chicane


G MV/m

BC2Chicane


G MV/m

2C-Band gun

6 GHz, 3.6? Cell 200 MV?


G MV/m


G MV/m

BC1Chicane


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


300 MV?

BC1Dogleg


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


G MV/m


300 MV?

BC1Chicane


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


G MV/m


G MV/m


15 MV/m


G MV/m

Undulatorlu ,K,

N? section

1S-Band gun

3 GHz, 1.6? Cell 100 MV?

BC1Chicane


G MV/m

BC2Chicane


G MV/m

2C-Band gun

6 GHz, 3.6? Cell 200 MV?


G MV/m


G MV/m

BC1Chicane


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


300 MV?

BC1Dogleg


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


G MV/m


300 MV?

BC1Chicane


G MV/m

Undulatorlu ,K,

N? section

BC2Chicane


G MV/m


G MV/m


G MV/m

𝐗𝟎 𝐗𝟏 𝐗𝟐

K/V/𝑁𝑜𝑛𝑒

Gradient Vs Length for Linearizers*

* Curtesy by X. Wu(WP4)

RF/Linearizers specifications

* a [mm] g [mm] l [mm] Eacc [MV/m] length [m] Voltage [MV]Klystron power

K-band(36 GHz)

2

2.17586 2.77586

30.46 0.66 20.104

3MW *41.8 37.41 0.54 20.201

2 29.595 0.75 22.196

2 25 0.75 18.75 2MW *4

V-band(48 GHz)

1.5 1.707 2.082 32.24 0.47 15.15282 MW *3

2 1.707 2.082 18.22 0.83 15.1226

𝐗𝟎 𝐗𝟏 𝐗𝟐

𝐾/𝑉

<a> [mm] Phase advance/cell [MV/m] Length[m]

X-band 3.5 120 65 (HX) (108 cells)*X. Wu(WP4)

<- old setting

K-band (36 GHz)

a=1.8mm, L=0.54m, g=37.4 MV/m a=2mm, L=0.66m, g=30.5 MV/m

BC1BC1

BC1 BC1

INJINJ

INJ INJ

BC2

BC2

BC2

BC2

END

END

END

END

a=2mm, L=0.75m, g=29.6 MV/m a=2mm, L=0.75m, g=25 MV/m

Improved from Helsinki ->

𝐼 > 5𝑘𝐴Δ𝐸

𝐸< 0.05%

Bunch length < 2um

t[mm/c]

A. Aksoy

Bonus I: V-band(48 GHz)

a=1.5mm, L=0.47m, g=32.2 MV/m a=2mm, L=0.83m, g=18.2 MV/m


𝐸< 0.05%

Bunch length < 2um

BC1INJ

BC2 END

BC1INJ

BC2 END

Bonus II: without linearizer!

Longitudinal wakefield from the x-band structure works like a passive linearizer.


𝐸< 0.05%

Bunch length < 2um

BC1INJ

BC2 END

X0

X1

BC1INJ

BC2 END

X0

X1

LINAC design results in terms of linearizers

a[mm]-L[m]𝝓𝟎

[degree]Linearizer

[MV]𝑹𝟓𝟔,𝑩𝑪𝟏

[m]𝝓𝟏

[degree]𝑹𝟓𝟔,𝑩𝑪𝟐

[m]𝝓𝟐

[degree]

k-band(36GHz)

1.8-0.54 11.24 6.06 -0.0258 37.73 -0.0064 27.19

2-0.66 13.43 9.59 -0.0214 41.36 -0.0053 32.62

2-0.75 17.15 19.06 -0.0146 37.08 -0.0055 -16.56

2-0.75 [L]* 13.25 7.06 -0.0214 36.53 -0.0063 -1.02

v-band(48GHz)1.5-0.47 22.20 14.26 -0.0113 25.14 -0.0063 33.17

2-0.83 21.27 12.46 -0.0117 23.21 -0.0074 13.28

none- 9.51 - -0.0273 29.97 -0.0088 -18.34

- 8.34 - -0.0307 29.11 -0.0094 -16.79

* Low gradient, namely the old setting for k-band structure• All cases fulfil the requirements• Two-chicane layout turns out to be better• Required voltage for k-band is lower than linear estimation• Synchronize phase for LINAC-1 and LINAC-2 is large, further optimization can be done

Wakefield dominated design !

𝑉𝑙𝑛𝑧 =1

ℎ2𝑉𝑥𝐶𝑜𝑠 𝜙𝑥 , ℎ𝑘 = 3, hv = 4

Lattice Design and module layout*

*A. Aksoy (WP6), WP2 meeting, Sep 13, 2019https://indico.cern.ch/event/847553/

https://indico.cern.ch/event/847553/

InjectorLINAC-end

X+K scheme 3D Simulation for LINAC* *A. Aksoy (WP6), WP2 meeting, Sep 13, 2019https://indico.cern.ch/event/847553/

https://indico.cern.ch/event/847553/

Status of S2E Modeling for X+K scheme

Injector LINAC FEL/undulator

1D Design

• Longitudinal beam dynamics

• HX based Linac parameters

• SX mode operation optimization

• Linearizer RF parameters and bunch compressor

3D Design

• Transverse/longitudinal beam dynamics

• Lattice design and module layout

• Verify with 1D optimization results

• Optimize the lattice design & linaclayout

Stability & Tolerance

Study

• (1D tested)

• HX mode

• SX mode

WP43D Design

• 3D tracking with space charge for x-band injector 1D analysis

• Undulator reviews

• Scheme comparison

• Semi-/analytical tools and simulation tools

3D simulation

• undulator design

• FEL performance evaluation

We’re here!

Summary and coming work

• Conclusion• 1D optimization tool is powerful and there are many working cases for different• For X+K scheme, different linearizer design will result in different linac settings and

they all seem good. Needs to be check in 3D simulation.

• Coming work• A. Aksoy pointed out that there is discrepancy between 1D results (with Track1D)

and 3D results (with PLACET), the reason(s) must be understood• Longitudinal beam intensity profile needs to be improved in 3D simulation• Undulator simulation to be included with existing/coming beam distribution to

complete the S2E simulation workflow• Synchronize with other schemes (e.g. S+X+K, C+X+K, no K) in progress/simulation

tools• Tolerance/stability study in 3D case

x-band based injector layout: s2e modelling€¦ · 3d design •3d tracking with space charge for...

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