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Page 1: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 1

PITZ Shutdown 2007

J.Bähr

PITZ, DESY

Technisches Seminar 3.Juli 2007

Page 2: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 2

Outline• Outline

1. Introduction

2. Explanations: PITZ, XFEL, Emittance,…

3. PITZ more detailed

4. Shutdown: Why and what

5. Manpower and coordination

6. Outlook

Page 3: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 3

1.Introduction- A long shutdown at PITZ is planned starting

from 20/08/2007 until beginning of November

- Most modules of the vacuum beamline will be dismounted and re-mounted in a new scheme

- The Conditioning Test Stand (CTS) will be mounted in the tunnel bearing gun 4.1

- The rf system 1 will be re-organized for the use of a 10 MW klystron

- Many further tasks

Page 4: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 4

2. Explanations: PITZ, XFEL, Emittance …

• What is that:• PITZ,XFEL,FLASH,emittance, laser, SASE,

space charge, electron gun…• What is the connection between:

– FEL and emittance– Emittance and space charge– A gun and a TV tube– PITZ and the XFEL,FLASH– …

Page 5: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 5

Setup PITZ1.6 completed !transverse emittance

gunboosterquads

longitudinal phase space masks

Gun

Page 6: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 6

PITZ• PITZ:“ Photo injector

Test Facility“• Test and optimize

electron sources for FELs: FLASH,XFEL

• X-FEL:

European X-ray FEL project

e-gun

Page 7: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 7

„FEL-Microscope“• FEL: „Free Electron Laser“:

„Microscope“ Motivation!!!• Resolution R:

about wavelength R~ λ

for microscopes• The higher the beam

energy , the smaller • better) the resolution R of

the „microscope“• c=νλ ,E=hv E=hc/λ

λ~1/E • Resolution ~ λ~1/E

• Resolution of microscopes

Device Energy

Electron/

photon

Resolution Object

Light micro-scope

1 eV (light) 1 µm Biologic cell

Electron micro-scope

~70 keV ~O(10 nm)

Magnifica-tion: 10**5

Big molecules

FLASH 500 MeV/

200eV

~7nm Molecules

XFEL 3 GeV ~1 Angstr. Atoms

Page 8: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 8

FEL

• FEL: Free electron laser :SASE principle

e-GunLinear accelerator Undulator: Magnetic structure

E-beam

Light/electro-magnradiation

Beam dump

SASE principle:„Self amplified radiation by stimulated emission“

PITZ

Page 9: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 9

The gun

• The gun:– Laser input port – Cathode– rf coupler– Solenoid magnets– Resonator– Vacuum tubes

Page 10: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 10

Comparison of an e-gun and a TV tubeGun-TV

TV Gun

Bild Bild

Cathode thermal Photo effect acceleration Electro static Rf Voltage accel. ~4kV ~6 MV Electron energy ~4 keV

W=Q*U=1e*4kV 6 MeV

El. Field strength E=U/d=4kV/0.2m=20kV/m 60MV/m Deflection Electro static Dipole magnet (if

wanted visualisation TV screen + eye Flourescence screen

+ TV camera (no access)

radiation X-rays X-rays Create image deflection Move laser spot

Page 11: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 11

Comparison between TV tube and an electron gun

Focusing using solenoids

Page 12: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 12

Mis-unerstanding• If one does not consider the motivation and

the context one could assume:

• PITZ is a not effective designed, rather huge built TV tube with enormous running parameters, where one has no access and the TV program is not interesting for typical citizens and difficult to regard and only remotely because there is no access possible. The screen size is much too low (about 2“).

Page 13: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 13

FLASH• FLASH: Free electron LASer in Hamburg

• (earlier TTF)

Brilliance: Photons in solid angle and per area unit pro wavelength intervall

Gun

LINAC Undulator

PITZ

Page 14: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 14

Laser• LASER: „Light Emission by Stimulated Emission of

Radiation“• Characteristics of laser light:

1. High energy density :“parallel“ ray of light instead of divergent bundle

2. Coherence: phase relations between parts of the light ray: possibility of interference Holography

3. Monochromatic light: only one wavelength (visible-invisible)

Resolution R~ λ~1/E

Page 15: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 15

Electromagnetic spectrum

Resolution R~ λ~1/E

Page 16: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 16

Emittance• Emittance : Characteristic of electron

beam• For FEL small emittance

necessary!!!• Optimization of e-gun:

Minimalization of transverse emittance

• - EMSY: Emittance measurement system

• Emittance cannot be improved after the source!!

• Emittance

• Divergent electron beam• ε : diameter * angle• ε = d * α in mm *mrad• Example : • Beam diameter : 1mm• Divergence α =0.05 °=

1mrad ε = 1mm mrad

d

α

Page 17: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 17

Space charge and emittance• Space charge:• 10,000,000,000 electrons

per bunch (1 nC)• About 1mm³ bunch size strong forces• What is to be done:

– Solenoid magnet: focusing– High acceleration in the gun

40MV/m 60 MV/m /June 2007)

– Laser profiles:long.,transv.– 1nC = 0.000,000,001 As– In 1ps = 0.000,000,000,001s– 1nC in 20 ps: 50A in 20ps

• Longitudinal Laser profile: rectangular

• Transverse Laser profile : rectangular

Page 18: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 18

Emittance

1. What emittance has been measured by PITZ?

2. What are the goals?

3. World record?

Page 19: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 19

εx,y ~ (e- beam size) • (e- beam angular divergence)

Why injector so important ?What is emittance ?

Why it must be small ?

n = 1mm mrad

length of the undulator

n = 2 mm mrad

n = 4 mm mrad

Q = 1 nCou

tpu

t p

eak

po

wer

of

th

e V

UV

-FE

L @

6.4

nm

(

GW

)

path length in the undulator (m)

VUV-FEL

peak power

• smaller emittance new horizons: shorter wavelength, higher repetition rate

• XFEL goal: 0.9 mm mrad@injector = 1.4 mm mrad@undulator

n = 1 mm mrad

ou

tpu

t p

eak

po

wer

of

th

e X

FE

L S

AS

E2

@ 0

.1 n

m

(G

W)

path length in the undulator (m)

n = 2 mm mrad

n = 3 mm mrad

peak current: 5 kAenergy spread: 2.5 MeV

XFEL

absolute numbers

Page 20: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 20

Emittance• Emittance results:

0.8

1.2

1.6

2.0

2.4

2.8

3.2

320 322 324 326 328 330Imain, A

no

rm. e

mit

tan

ce /

mm

mra

d ExEySQRT(Ex*Ey)measured @ PITZ:

p = 5.2 MeV/c

Q = 1 nC = m

Ibuck = Imain * 0.075(100% rms projected emittance)

Results fromPITZ1: 2005 (Gun1) VUV-FEL13nm

XFEL

WR

VUV-FEL 6nm

Page 21: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 21

Emittance• Results 2006: Gun3.1

0,5

1,0

1,5

2,0

2,5

3,0

278 280 282 284 286 288 290Imain [A]

no

rm. p

roje

cte

d e

mit

tan

ce

[mm

mra

d]

Emitt(x)Emitt(y)

ASTRA simulation

Page 22: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 22

Setup PITZ1.6 completed !transverse emittance

gunboosterquads

longitudinal phase space masks

Page 23: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 23

Present layout of PITZ

Page 24: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 24

PITZ• Simplified scheme

DDC

Rf-coupler

rf

Laser beam

E-gun

Diagnostics

Booster cavityDiagnosticsBeam dump

Not in scale!!

Page 25: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 25

PITZ diagnostics

Measure Device

Beam:Profile, diameter Screen station (TV), wire scanner

Charge Faraday cup,

ICT (Integrating current transformer)

Beam energy Spectrometer,

dipole magnet

Bunch length Streak camera

Emittance EMSY

Page 26: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 26

PITZ : Auxiliary system• Auxiliary systems• Vacuum

• Photocathode laser and laser beamline

• Cooling and climatization

• Rf system: 2 Klystrons 5-10 MW, modulators,…

• Electronics

• Controls

Page 27: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 27

PITZ history

PITZ history Year Gun Project

stage Remarks

1999 Decision directorate 2000 Construction 2001 Gun2 PITZ1 Commissioning 13/01/2002 Gun2 PITZ1 1st photoelectrons 2003 Gun2 PITZ1 Nov.:Gun2: HH 2004 Gun1 Dec.: upgrad 2005 Gun1 PITZ1.5 Upgrade, booster,

10MW klystron 2006 Gun1 PITZ1.6 57MW/m Gun3.1 Conditioning,

Characterization, Gun3.1HH

2007 Gun3.2 PITZ1.6 Cond.,Charact. 2007 PITZ1.7

Page 28: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 28

PITZ : The shutdown• Why?• Insert HEDA1: High energy

dispersive arm• Move booster downstream

(higher gun gradient)• Space for new CDS booster

(2008)• Minor change of sequence

of diagnostics elements• Prepare for PITZ 2

beamline 2008• Reconstruction of low

energy section (New DDC,..)

• Further tasks• Extension of laser hutch• New laser• New klystron 10MW for rf1• New technical interlock• Many small tasks

– TV system– Exchange YAG screen– EMSYs…– …

• PITZ1.6 PITZ1.7

Page 29: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 29

PITZ : The shutdown• Major changes in beam

line

GunBooster

Dipole Diagnostics Beam dump

Beam dump

Reconstructed low energy section

HEDA1

New HEDA1

HE diagnostics

modified

PITZ1.6

PITZ1.7

Page 30: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 30

PITZ 1.6, PITZ 1.7PITZ 1.6

PITZ 1.7

Page 31: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 31

PITZ : The shutdown• Vacuum work:

– Dismount modules– CTS: Conditioning test stand:

Gun 4.1– Mount modules – Mount HEDA1– Reconstruction Low energy

section:• DDC• Dipole…

– ……– Parallel work of two teams New dipole HEDA1 – 180 grad

Page 32: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 32

PITZ : The shutdown• RF group:• Reconstruction rf system1• Exchange klystron 5MW10MW• Waveguides to CTS• Investigation of T-combiner • ………

• Electronics:• New technical interlock• Connect all new/moved components, tests• ……….

Page 33: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 33

PITZ : The shutdown• Controls

• Control and data aquisition of elements of reconstructed beam line and CTS

• Control for new laser

• Control of rf1

• …..

Page 34: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 34

PITZ : The shutdown• Technical infrastructure• Second crane in tunnel• Reconstruction laser hutch• New climatisation and cooling for laser and

laser hutch• Extension of cooling in tunnel new elements

and CTS• Upgrade of cooling systems• ……• Partially done by external firms

Page 35: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 35

PITZ : The shutdown• Laser hutch and laser• Extension of Laser: longitudinal profile: flat top with

rise and fall time of 1-2ps(10**-12)• Dismount laser• Extension of laser hutch• Climatisation, cooling , network, electric power• Cleaning• Mount new laser table• Mount new laser• Commissioning of laser: Beginning of November

Page 36: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 36

PITZ : The shutdown• To do: Preparation and during shutdown

• Sequence of work

• Coordination between technical groups

• Delivery of components

• End of shutdown

• Start running with new laser in test mode: Beginning of November

Page 37: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 37

PITZ : The shutdown• Flow chart

Page 38: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 38

PITZ : Outlook• Outlook

• PITZ1.7 PITZ 2 : 2008• HEDA2 :July 2008• Tomography module (March 2008)• Magnets• Rf deflector as option• CDS Booster (Jan. 2008) • Beam dump : 2m³ concreteJuly 2008

Page 39: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 39

Comparison: PITZ1.6 ↔ PITZ2.0PITZ1.6:

PITZ2.0:

TESLA

CDS

• dipole is ready and tested,• technical design of dispersive arm ready,• parts in fabrication• installation starting August 20

• preliminary dispersive arm and beam dumps have to be replaced by final components• physics design is ongoing• sweeper under fabrication

tomography module + RF deflector are realized depending on EU contracts,basic design available for both devices

tomography module + RF deflector are realized depending on EU contracts,basic design available for both devices

Page 40: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 40

Acknowledgement• Thanks to F.Stephan, S. Rimjaem and S.

Khodyachykh for providing transparencies and photos

• Thanks to S.Niedworok and Chr. Iezzi for the poster

Page 41: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 41

PITZ shutdown 2007

• The end

Page 42: PITZ Shutdown 2007

J.Bähr, PITZ, Technisches Seminar, 3.Juli, 2007يح- 42

0,8

1,2

1,6

2,0

2,4

2,8

3,2

320 322 324 326 328 330

Imain, A

norm

. em

ittan

ce /

mm

mra

d ExEySQRT(Ex*Ey)measured @ PITZ:

p = 5.2 MeV/c

Q = 1 nC = m

Ibuck = Imain * 0.075(100% rms projected emittance)

Results from PITZ1:

Particularities, Results from PITZ1• PITZ source must drive super conducting linac long pulse trains, i.e. high average power, good stability

• XFEL goes to very short wavelength very good emittance required

0.2

0.3

0.4

0.5

0.6

0.7

800 1000 1200 1400 1600 1800 2000 2200

t / sec

a.u. Forw ard pow er

R eflected pow er

e.g. 800 µs

~ log(power)long RF pulse:

amplified output train

pulse train from the oscillator

10 Hz, 800µs, 1 MHz

long laser pulse train:

VUV-FEL, 6nm

XFEL

C

WR

measured @ VUV-FEL:

p = 127 MeV/c

Q = 1 nC

• regularly obtain 2.1 mm mrad (100% rms projected emittance)

• minimum 1.1 mm mrad (90% rms projected emittance)

PITZ gun installed at VUV-FEL in 2004

Page 43: PITZ Shutdown 2007

first preliminary emittance results (not optimized yet !)

in operation: gun + booster 13.7 MeV/c

current booster: TESLA prototype

3,5

4

4,5

5

5,5

6

6,5

7

7,5

2 3 4 5 6 7 8

gun peak power, MW

Pm

ean

, MeV

/c

38,4 44,3 49,6 54,3 58,7 62,7Ecath, MV/m

max. mean momentum ↔ gun power

goal: 60 MV/m

measured at PITZ2 (momentum of dark

current edge)

p = 12.8 MeV/c, Q = 1 nC,gun = max_p, booster = min_dp

obtained at PITZ1

0

1

2

3

4

5

6

7

8

262 264 266 268 270 272 274 276 278 280 282

Imain, A

Em

itta

nce

, [m

m-m

rad

]

Xemittance, measured

Yemittance, measured

Simulation (ASTRA)

First Results from PITZ2

Status: • new gun cavity (#3) installed and under conditioning now• upgrade of beamline ongoing


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