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Current Pojects |
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I am presently designing electron beam diagnostics for the PSI X-ray free electron laser (Swiss FEL).
I am involved in the following projects:
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Diagnostics for the SwissFEL Injector Test Facility
To demonstrate the feasibility of the Swiss FEL project, we are presently designing a test accelerator that will accelerate electrons to an energy of 250 MeV. I am developing instrumentation to measure slice parameters of the electron beam.
 Group weblog (available only from PSI and ETHZ computers)
Wiki (available only from PSI and ETHZ computers)
Media gallery: Overview
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Transverse Profile Monitors
Profile monitors, consisting of YAG and LuAG scintillators, OTR targets and wire scanners, are installed at several locations along the SwissFEL Injector Test Facility.
Media gallery
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Open Positions |
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We currently have open positions:
Internship
Characterization of ultraviolet transition radiation monitor for SwissFEL
Please let me know if you would like to apply!
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Previous Projects at SLAC, DESY and RWTH Aachen University |
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Plasma Wakefield Acceleration
Free electromagnetic waves in vacuum have a transverse electric fields
and are therefore of limited use for particle acceleration. In conventional
radio-frequency (RF) accelerators, a metallic cavity is used to confine
the electromagnetic field and to allow a mode with a longitudinal component.
However, the field and therefore the energy gain is limited by breakdown
effects on the material surface.
This difficulty could be overcome by employing plasma waves for particle
acceleration. Unlike electromagnetic waves in vacuum, these can have
a longitudinal component. The electric field can reach very high values
of several Gigavolt per meter.
Proposal for our experiment E-167
Media gallery
Group homepage
Group weblog (available only from SLAC computers)
Publications and Presentations
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Photonic Band Gap Fiber Accelerator
Under certain circumstances, a hollow-core quartz fiber has an electromagnetic
mode that has a longitudinal electric field whose phase velocity is
equal to the speed of light. These fibers could possibly be used to
accelerate relativistic particles.
Media Gallery
Weblogs: Photonic Band Gap Studies, Experimental Verification (available only from SLAC computers)
Publications and Presentations
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Measurement of Bunch Length using Coherent Radiation
The electric field that can be achieved in a plasma wakefield accelerator
depends on the beam current that enters the plasma. Characterization
of sub-picosecond electron bunches is not trivial, and several methods
are employed, to determine the length and possibly the shape of the
bunch.
Read more...
Media gallery
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Characterization of Cameras for Accelerator Use
Cameras are used to determine the transverse shape of the electron
beam. The light created by optical transition radiation (OTR) is imaged
on a CCD detector. The performance of these cameras is being evaluated.
Read more...
Gallery: cameras in the TTF accelerator
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VUV Free Electron Laser Photon Diagnostics
PhD thesis / Doktorarbeit
Abstract
Zusammenfassung
PDF: colour
version (one column, 12pt font, 15MB)
PDF: black-and-white
version (two columns, 10pt font, 13MB)
Disputation / Defense
Deutsch: PDF
(4.3MB)
English: PDF
(4.2MB)
Figures from the thesis (PDF and JPG, respectively)
Photo gallery: Coherence measurements
Media gallery: TESLA Test Facility and VUV Free Electron Laser
Publications and Presentations
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Timing measurements with Electro-Optical Sampling
Group weblog (password required)
Publications and Presentations
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Data Acquisition
Concept of a data acquisition system for TTF
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Beam Trajectory Monitor
Photo gallery
Project details
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Public Relations
Transparencies of my talk for DESY visitors
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Twin Microstrip Gas Detectors
Diploma thesis
Gallery
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F-Praktikum
Gallery
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Selected Publications |
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See a full list of publications here |
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Please note that most articles are copyrighted by the journal.
They may require a subscription or charge a fee for downloading the
full text. However, I would be happy to send you a reprint, if you like.
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| 2009 |
R. Ischebeck et al.
Screen Monitor Design for the SwissFEL
Proceedings of DIPAC2009
Full text |
| 2008 |
M. Thompson et al.
Breakdown Limits on Gigavolt-per-Meter Electron-Beam-Driven Wakefields in Dielectric Structures
Phys. Rev. Lett. 100, 214801 (2008)
Full text (requires subscription of the journal) |
| 2007 |
C. Huang et al.
Hosing Instability in the Blow-Out Regime for Plasma-Wakefield Acceleration
Phys. Rev. Lett. 99, 255001 (2007)
Full text (requires subscription of the journal)
E. Oz et al.
Ionization-Induced Electron Trapping in Ultrarelativistic Plasma Wakes
Phys. Rev. Lett. 98, 084801 (2007)
Abstract
Full text (requires subscription of the journal)
I. Blumenfeld et al.
Energy Doubling of 42 GeV Electrons in a Metre-Scale
Plasma Wakefield Accelerator
Nature 445, p. 741 (2007)
Abstract Full text (requires subscription of the journal)
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| 2006 |
D. Johnson et al.
Positron Production by X Rays Emitted by Betatron Motion in a Plasma Wiggler
Phys. Rev. Lett. 97, 175003 (2006)
Abstract
Full text
(requires subscription of the journal)
V. Ayvazyan et al.
First operation of a free-electron laser generating
GW power radiation at 32 nm wavelength
Eur. Phys. J. D
Abstract
Full text
(requires subscription of the journal)
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| 2005 |
K. J. Gaffney et al.
Observation of Structural Anisotropy and the Onset
of Liquidlike Motion During the Nonthermal Melting of InSb
Phys. Rev. Lett. 95, 125701 (2005)
Abstract
Full text
(requires subscription of the journal)
A. Cavalieri et al.
Clocking Femtosecond X Rays
Phys. Rev. Lett. 94, 114801 (2005)
Abstract
Full text
(requires subscription of the journal)
A. M. Lindenberg et al.
Atomic-Scale Visualization of Inertial Dynamics
Science 15 April 2005; 308: 392-395
Full text (requires
subscription of the journal)
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| 2003 |
R. Ischebeck
Transverse Coherence of a VUV Free Electron Laser
Doktorarbeit, Universität Hamburg
Abstract (english)
Zusammenfassung
(deutsch) Full
text (colour) Full
text (b/w)
V. Ayvazyan et al.
Study of the statistical properties of the radiation
from a VUV SASE FEL operating in the femtosecond regime
Nucl. Instrum. Meth. A 507 (2003), 368–372
Abstract
Full
text (requires subscription of the journal)
R. Ischebeck et al.
Study of the Transverse Coherence at the
TTF Free Electron Laser
Nucl. Instrum. Meth.
A 507 (2003), 175–180
Abstract
Full
Text (requires subscription of the journal)
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V. Ayvazyan et al.
A new powerful source for coherent VUV radiation:
Demonstration of exponential growth and saturation at the TTF free-electron
laser
Eur. Phys. J. D 20 (2002) 1, 149-156
Abstract
Full
text (requires subscription of the journal)
V. Ayvazyan et al.
Study of the Statistical Properties of the
Radiation from a VUV SASE FEL Operating in the Femtosecond Regime
Nucl.Instrum.Meth.A507:368-372,2003
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| 2001 |
V. Ayvazyan et al.
Generation of GW Radiation Pulses from a
VUV Free-Electron Laser Operating in the Femtosecond Regime
Phys. Rev. Lett. 88, 104802 (2002)
Abstract
Full
text (requires subscription of the journal)
S. Hillert et al.
Test Results on the Silicon Pixel Detector
for the TTF-FEL Beam Trajectory Monitor
Nucl. Instrum. Meth. A 458 (2001) 710-719
Abstract
Full
text (requires subscription of the journal)
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| 2000 |
J. Andruszkow et al.
First Observation of Self-Amplified Spontaneous
Emission in a Free-Electron Laser at 109 nm Wavelength
Phys. Rev. Lett. Oct 30, 2000 - Vol 85, Iss
18, pp. 3825-3829
Abstract
Full
text (requires subscription of the journal)
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| 1999 |
M. Ackermann et al.
Large scale test of wedge shaped Micro Strip
Gas Counters
Nucl. Instrum. Meth. A 436 (1999) 3, 313-25
Abstract
Full
text (requires subscription of the journal)
R. Ischebeck
Bau eines Zwillings-Mikrostreifengasdetektors
zur Bestimmung der zweiten Ortskoordinate in der Vorwärts-Spurkammer
des CMS
Diplomarbeit, PITHA 99/01
Abstract
(english) Zusammenfassung
(deutsch) Volltext
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More Publications...
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Selected Talks |
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Click here to see all presentations.
Please note that slides showing unpublished results have been removed.
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Free Electron Laser Conference in Shanghai, China
Talk:
SwissFEL Longitudinal Diagnostics Response Matrix
Download Slides (PDF, 2.8 MB)
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Beschleunigerseminar in Mainz, Germany
Talk:
The X-Ray Laser SwissFEL
Download Slides (PDF, 12.3 MB)
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Seminar at SPring8, Japan
Talk:
SwissFEL Diagnostics Layout
Download Slides (PDF, 6 MB)
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X-Ray Science at the Femtosecond to Attosecond Frontier in Los Angeles, California
Invited Talk:
Synchronization and Longitudinal Diagnostics for XFELs
Download Slides (PDF, 13.9 MB)
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SLAC National Accelerator Laboratory in Menlo Park, California
Talk:
The PSI XFEL
Download Slides (PDF, 7.3 MB)
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Kolloquium der LMU und TU München, Germany
Invited Talk:
Advanced Accelerator Concepts
Download Slides (PDF, 12.6 MB)
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DPG Frühjahrstagung in München, Germany
Invited Talk:
Beschleuniger jenseits von LHC und ILC
Download Slides (in German; PDF, 10.4 MB)
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Paul-Scherrer-Institut in Villigen, Switzerland
Invited Talk:
Energy Doubling of 42 GeV Electrons in a Plasma Wakefield Accelerator
Download Slides (PDF, 4.3 MB)
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Colloquium at the Max-Planck-Institut für Physik (Werner-Heisenberg-Institut) in Munich, Germany
Invited Talk:
Accelerators Beyond LHC and ILC
Download Slides (PDF, 3.9 MB)
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Group Seminar at the Max-Planck-Institut für Quantenoptik in Munich, Germany
Energy Doubling of 42 GeV Electrons
Download Slides (PDF, 3.5 MB)
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Stanford Collider Seminar at Stanford, California
Invited Presentation:
Advanced Accelerator Research
Download Slides (PDF, 2.8 MB)
Download Handout (PDF, 0.1 MB)
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Linear Accelerator Conference 2006 in Knoxville, Tennessee
Invited Talk:
Energy Doubling of 42 GeV Electrons
Download Slides (PDF, 2.6 MB)
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Advanced Accelerator Concepts Workshop 2006 in Lake Geneva, Wisconsin
Invited Talk:
Energy Doubling of 42 GeV Electrons
Download Slides (PDF, 2.1 MB)
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Beschleunigerseminar, Universität Hamburg / DESY in Hamburg, Germany
Invited Talk:
Electron Acceleration by 43 GeV in a Plasma Wakefield Accelerator
Download Slides (PDF, 10.8 MB)
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APS, Division of Plasma Physics, Annual Meeting in Denver, Colorado
Invited Talk:
First Results of the E-167 Experiment
Download Slides (PDF, 5.6 MB)
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Disputation / Thesis Defense at Universität Hamburg, Germany
Transverse Coherence of a Vacuum Ultraviolet Free Electron Laser
Räumliche Kohärenz eines Freie-Elektronen-Lasers im Vakuum-Ultraviolett
Download English Slides (PDF, 4.2 MB)
Download German Slides (PDF, 4.3 MB)
Download Included Movies (ZIP, 67.8 MB)
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Free Electron Laser Conference FEL2002 in Argonne, Illinois
Invited Talk:
Study of the Transverse Coherence at the TTF Free Electron Laser
Download Slides (PDF, 1.7 MB) |
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More Talks...
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Posters |
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PAC 2005
Bunch Length Measurements using Coherent Radiation
PDF
(9.8MB)
PAC 2005
Resolution of Transverse Electron Beam Measurements using Optical Transition
Radiation
PDF
(2.8MB)
EPAC 2004
Measurement of the Transverse Coherence of a VUV Free Electron Laser
PDF
(3.8MB)
Coherence Measurements — First Results
PDF medium
resolution (1MB) — high
resolution (6MB)
The TTF & FELTeam
PDF
(11MB)
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Computer Programs |
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Optimization of LiTrack with a Genetic Algorithm
Optimizes a LiTrack simulation to achieve a goal such as fitting the measured energy spectrum. Description — Source Code (MATLAB)
CIA — Camera Image Acquisition
Allows to take pictures with the digital and anslogue cameras in the
accelerator. Performs a variety of filters and analysis routines on
the images. (Replaces Camera
Tool and Image
Processing (Photondiag))
Source
Code (MATLAB) ZIP
file
DAQ — Data Acquisition for the TTF
Stores data from the accelerator in ROOT files.
Description
— Source
Code (C++)
ScanTool
Varies one parameter of the accelerator and observes and records the
effect on one or several measured variables.
Screenshot
— Source
Code (MATLAB)
Analysis Routines to determine the Transverse Coherence of
the FEL
I have written these MATLAB analysis routines for my PhD thesis. Only
the most interesting functions are given here, the more technical stuff
(like plotting) is available upon request.
image processing: correction for detrimental effects of the fluorescent
crystal and of the camera optics: processimage.m
first analysis method: determine the visibility in the centre of the
diffraction pattern: analysis_vis.m
function that finds maxima and minima: find_maxima.m
second analysis method: fit a function that accounts for the near
field diffraction pattern to the data: analysis_fit.m
The fitted function: intenserrvec5.m
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Files for internal access |
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FLADocuments
Publications
(globally accessible) — Media
(accessible within the DESY network) — Plots
(globally accessible)
new FLA library
Photon Diagnostics
Papers
— Talks
— Media
(Photos, Movies, Drawings, Logos) — Plots
(requires password)
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See also... |
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my private home page (which has not been updated in years...)
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Photos from the LINAC10 Social Event |
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Photos from the Future Light Sources workshop FLS2010 at SLAC |
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Photos from the Mini-Workshop on Characterization of High Brightness Beams, 26-30 May 2008 at Zeuthen |
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Connect with me on Facebook, xing.com or linkedin.com |
