ELBE Superconducting RF Photoinjector

                                 
  SRF-Gun Logo  

ELBE Superconducting RF photoinjector (SRF Gun)

 SRF-Gun Design Cryostat  
   

 

  
                                 
 
                                 
 

Introduction

The production of beams with low-emittance as well as high average current is one of the key techniques for future electron accelerators and next generation light sources. The superconducting radio-frequency photo electron source (SRF gun) has the potential to fulfil these requirements. Even though proposed about twenty years ago (pdf_1) the SRF gun is still a subject of research and development. The greatest challenges have been the development of a suitable acceleration cavity and the difficulties associated with the photo cathode. But within the last years remarkable progress has been achieved.

 

In 2002, it was shown in a proof-of-principle experiment with a niobium half-cell cavity at HZDR that a normal-conducting semiconductor photo cathode can be operated in a superconducting cavity, and the first electron beam could be produced with a SRF gun (pdf_2)

 

In 2004 the project for the ELBE SRF gun was launched. The goals of this project are to build a new electron source with 1 mA average current in cw-operation and low emittance for the ELBE superconducting linear accelerator, as well as to demonstrate the capability for the future applications in FEL light sources and energy recovery linacs. The injector together with the UV driver laser system and the diagnostic beam line were developed and constructed in collaboration with the German institutes DESY, HZB, MBI, and the project was one task in the Coordinated Accelerator Research in Europe (CARE) activity supported by the European Commission. Furthermore there has been a strong financial support by the German Federal Ministry of Education and Research. The SRF gun project at HZDR has two main goals: the installation of a high-brightness photo-injector for ELBE, and contributing to the SRF gun development as a promising future technology. Now the operating SRF gun has opened a unique opportunity for experimental studies like long term photo cathodes operation and lifetime, cavity quality degradation, or emittance compensation methods.

 

  •         The SRF gun was installed in the ELBE accelerator hall in summer 2007.

  •         On November 12, 2007, the first accelerated electron beam was generated which was extracted from a Cu photo cathode. (first beam 12.11.2007)

  •         In March 2008 the cathode transfer system was mounted and the first set of Cs2Te photo cathodes was produced. Since May 2008 the gun has been operated with these cathodes.

  •         In the winter shutdown 2009/10 the connection beam line was installed, which now allows to inject the electron beam into the ELBE accelerator.

  •         In February 2010 the SRF gun beam was injected into ELBE for the first time. After some shifts for machine optimisation and beam parameter studies, it is scheduled to use the beam for user experiments.  

        
 
   
                                 
 

Parameters

  
                                 
     
parameter
present cavity
new cavity – design parameters
measured ´08
ELBE
high charge
ELBE
high charge
final electron energy
2.1 MeV
3 MeV
≤9.5 MeV
peak field
13.5 MV/m
18 MV/m
50 MV/m
laser rep. rate
1 – 125 kHz
13 MHz
2 – 250 kHz
13 MHz
≤500 kHz
laser pulse length (FWHM)
15 ps
4 ps
15 ps
4 ps
15 ps
laser spot size
2.7 mm
5.2 mm
5.2 mm
2 mm
5 mm
bunch charge
≤ 200 pC
77 pC
400 pC
77 pC
1 nC
max. aver. Current
1 µA
1 mA
100 µA
1 mA
0.5 mA
peak current
13 A
20 A
26 A
20 A
67 A
transverse. norm. emittance (rms)
3±1 mm mrad 
2 mm mrad
7.5 mm mrad
1 mm mrad
2.5 mm mrad
@ 80 pC
  		      FZD SRF Gun cavity & cathodecooler  
                         
 
 
 

Documentation

A. Arnold Simulation und Messung der Hochfrequenzeigenschaften einer supraleitenden Photo-Elektronenquelle Dissertation,Fakultät für Informatik und Elektrotechnik der Universität Rostock, 2012
A. Arnold, et al. Theoretical and Practical HOM-Analysis of the Rossendorf SRF-Gun LINAC´12, September 09-14, 2012, Tel Aviv, Israel
R. Xiang, et al. Research Activities on Photocathodes for HZDR SRF Gun IPAC2012, New Orleans, USA, from May 20 - 25, 2012
J. Teichert, et al. Status and future plans for the SRF gun at ELBE FLS 2012– ICFA Beam Dynamic Workshop, March 5-9, 2012, Newport News, USA
J. Rudolph,  et al. Slice-Emittance Measurements at ELBE/SRF-Injector DIPAC 2011, May 16 – 18, 2011, Hamburg, Germany, p. 416
A. Arnold, J. Teichert Overview on superconducting photoinjectors Phys. Rev. Special Topics AB 14, 024801 (2011)
J. Teichert, et al. Operation of the superconducting RF photo gun at ELBE Journal of Physics: Conference Series 298 (2011) 012008
R. Xiang, et al. Cs2Te normal conducting photocathodes in the superconducting rf gun (pdf) Phys. Rev. Special Topics AB 13, 043501 (2010)
J. Teichert The New Superconducting RF Photoinjector – a High-Average Current & High-Brightness Gun (pdf) The Second Workshop on High Average Power & High Brightness Beams January 14-16, 2009, Los Angeles, USA
J.W. Lewellen, et al. ERL 2009 WG1 Summary Paper: Drive Lasers and RF Gun Operation and Challenges(pdf) Proc. ERL Workshop, Ithaca, USA, June 8-12, 2009
R. Xiang, et al. Running Experience of the Superconducting RF Photoinjector at HZDR(pdf) Proceedings of FEL´09, August 23-28, 2009, Liverpool, UK
R. Xiang, et al. The Properties of Normal Conducting Cathodes in HZDR Superconducting Gun(pdf) Proc. SRF 2009 Conference, Sept. 20-25, 2009, Berlin & Dresden, Germany
A. Arnold Overview of Superconducting Photoinjectors(pdf) Proc. SRF 2009 Conference, Sept. 20-25, 2009, Berlin & Dresden, Germany
P. Murcek, et al. Modified 3½-Cell SC Cavity Made of Large Grain Niobium for the HZDR SRF Photoinjector(pdf) Proc. SRF 2009 Conference, Sept. 20-25, 2009, Berlin & Dresden, Germany
R. Xiang, et al. Low Emittance Polarized Electron Source Based on HZDR Superconducting RF Gun(pdf) Proceedings of PST2009 , published by World Scientific. Oral contribution in the XIIIth International Workshop on Polarized Sources, Targets & Polarimetry (PST2009), September 07-11, 2009 , Ferrara, Italy
A. Arnold, et al. A high-brightness SRF photo electron injector for FEL light sources(pdf) Nucl. Instr. and Meth. A 593 (2008) 57
T. Kamps, et al. Electron beam diagnostics for a superconducting radio frequency photoelectron injector(pdf) Review of Scientific Instruments 79, 093301 (2008)
T. Kamps, et al. Commissioning of Electron Beam Diagnostics for a SRF Photoelectron Injector(pdf) 2008 Beam Instrumentation Workshop, May 4-8, 2008, Lake Tahoe, USA
J. Teichert, et al. Commissioning Results of the Superconducting Photo-Injector at ELBE(pdf) EPAC2008
J. Teichert, et al. Commissioning and Test Results of the Superconducting RF Gun at ELBE Sixth PHIN Collaboration Meeting, Lecce, 17 -18 July 2008
J. Teichert, et al. Status and Future of the SRF Gun Project at ELBE Sixth PHIN Collaboration Meeting, Lecce, 17 -18 July 2008
J. Teichert, et al. Initial Commissioning Experience with the Superconducting RF Photoinjector(pdf) Proceedings of FEL´08, August 24 -29, 2008, Gyeongju, Korea.
J. Teichert, et al. The Superconducting RF Photoinjector at ELBE – First Operational Experience(pdf) PESP workshop, October 1-3, 2008, Newport News, USA.
A. Arnold, et al. Measurements of the Rossendorf SRF-Gun Cavity Characteristics(pdf) PESP workshop, October 1-3, 2008, Newport News, USA.
J. Teichert, et al. The New Superconducting RF Photoinjector at the ELBE Linac The IEEE Nuclear Science Symposium and Medical Imaging Conference, Dresden19-25 October 2008, Germany
F. Staufenbiel, et al. Beam dynamics studies for a 3 ½ cell superconducting RF photo injector operating at low and high bunch charge (pdf) NIM A, Vol. 584(2008)259
K. Möller, et al. Development of a superconducting radio frequency photoelectron injector (pdf) NIM A, Vol. 577(2007)440
G. Klemz, I. Will A Beam Shaper for the Optical Beamline of RF Photoinjectors FEL2006, Berlin, Germany
I. Will, et al. Photocathode Laser for the Superconducting Photo Injector at the Helmholtz-Zentrum Dresden-Rossendorf FEL2006, Berlin, Germany
D. Janssen, et al. High Peak Current Design of a Superconducting Cavity for a SRF Photoinjector FEL2006, Berlin, Germany
A. Arnold, et al. First RF-Measurements at the 3.5-Cell SRF-Photo-Gun Cavity in Rossendorf FEL2006, Berlin, Germany
J. Teichert, et al. Cryomodule and Tuning System of the Superconducting RF Photo-Injector FEL2006, Berlin, Germany
D. Janssen, et al. Progress of the Rossendorf SRF Gun Project (pdf) EPAC2006
C. Beard, et al. 3-1/2 Cell Superconducting RF Gun Simulations (pdf) EPAC2006
F. Staufenbiel Advantages of the Superconducting 3½ Cell SRF Gun in Rossendorf (pdf) FLS2006 Workshop, DESY, Germany
D. Janssen, et al. Technology challenges for SRF guns as ERL sources in view of Rossendorf work NIM A, Vol. 557(2006)80
F. Staufenbiel, et al. Test of the photocathode cooling system of the 3½ cell SRF gun PHYSICA C, Special issue, (2006)
J. Sekutowicz Superconducting RF Photoinjectors (pdf) Phy. App. High Brigt Elec. Beam 2005
T. Kamps, et al. Diagnostics Beamline for the SRF Gun Project (pdf) FEL2005, California, USA
J. Teichert, et al. Progress of the Rossendorf SRF Gun Project (pdf) FEL2005, California, USA
F. Staufenbiel, et al. Status of the 3½ cell SRF gun project in Rossendorf (poster in pdf), (article in pdf) SRF2005, NY, USA, July 2005
A. Arnold, et al. Field Profile Measurement of the 3½ cell SRF-GUN (poster in pdf) SRF2005, NY, USA, July 2005
D. Janssen Review of Superconducting RF Guns (pdf) SRF2005, NY, USA, July 2005
R. Xiang, et al. Status of the 3½ cell SRF gun project in ROSSENDORF (pdf) PAC2005
D. Janssen Axial rf Power Input intoPhotocathode Electron Guns (pdf) PAC2005
D. Janssen, M. Dohlus The Influence of the Main Coupler Field on the Transverse Emittance of a Superconducting RF Gun (pdf) EPAC2004
D. Janssen, V. Volkov Emittance Compensation of a Superconducting RF Photoelectron Gun by a Magnetic RF Field (pdf) EPAC2004
J. Teichert, et al. A Superconducting Photo-Injector with 3+1/2- Cell Cavity for the ELBE Linac (pdf) EPAC2004
D. Janssen, et al. First operation of a superconducting RF-gun NIM A, Vol. 507(2003)314
V. Volkov, D. Janssen RF Focussing - An Instrument for Beam Quality Improvement in Superconducting RF Guns (pdf) EPAC2000
D. Janssen, et al. A Superconducting RF Gun Current Status of the Drossel Collaboration (pdf) PAC1999

 

  
Contact: Dr. Jochen Teichert .
Last modified: May 03, 2010