IPAC2013 - List of Authors (Khan, S.)

Paper	Title	Page
MOPEA014	Temporal and Spectral Observation of Laser-induced THz Radiation at DELTA	94
	P. Ungelenk, H. Huck, M. Huck, M. Höner, S. Khan, R. Molo, A. Schick DELTA, Dortmund, Germany N. Hiller, V. Judin KIT, Karlsruhe, Germany
	Funding: Work supported by the DFG, the BMBF, the Federal State NRW, the Initiative and Networking Fund of the Helmholtz Association, and the German Federal Ministry of Education and Research. Coherent THz pulses caused by a laser-induced density modulation of the electron bunches are routinely produced and observed at DELTA, a 1.5 GeV synchrotron light source operated by the TU Dortmund University. New measurements performed with a fast hot-electron bolometer allow insight into the turn-by-turn evolution of these pulses. Furthermore, first results from a Fourier transform infrared spectrometer, which is currently under commissioning, are presented.

MOPME008	Beam Diagnostics by Using Bunch-by-bunch Feedback Systems at the DELTA Storage Ring	485
	M. Höner, H. Huck, M. Huck, S. Khan, R. Molo, A. Schick, P. Ungelenk DELTA, Dortmund, Germany
	Funding: Work supported by BMBF (05K10PEB) At DELTA, a 1.5-GeV electron storage ring operated by the TU Dortmund University, longitudinal and transverse bunch-by-bunch feedback systems are in use to detect and suppress multi-bunch instabilities. Besides that, the digital feedback systems are excellent diagnostics tools. As an example, by exciting a certain number of bunches within the bunch train, the coupling to the non-excited bunches can be investigated below and above the instability threshold. Other examples include studies of the injection process and monitoring bunch oscillations during sudden beam loss. First experimental results will be presented in this paper.

TUPWO007	Investigation of the Magnetic Chicane of the New Short-Pulse Facility at the DELTA Storage Ring	1889
	R. Molo, J.A. Grewe, H. Huck, M. Huck, M. Höner, S. Khan, A. Schick, P. Ungelenk DELTA, Dortmund, Germany
	Funding: Supported by DFG, BMBF, and the Federal State NRW. The new short-pulse facility at DELTA (a 1.5-GeV synchrotron light source) based on coherent harmonic generation (CHG) utilizes an electromagnetic undulator which can be configured as optical klystron (undulator – chicane – undulator). To optimize the CHG signal, the energy modulation of the electrons in the first undulator and the dispersion of the magnetic chicane (i.e. the R56 matrix element) have to be optimized. Since the R56 value of the present chicane is not sufficient, it is planned to rewire the magnetic coils to create a more efficient chicane. Simulations of the present chicane will be compared to measurements of the R56 matrix element and a new chicane configuration will be presented which increases the R56 value by a factor of ten.

WEPWA005	Experimental Characterization of the Coherent Harmonic Generation Source at the DELTA Storage Ring	2132
	M. Huck, H. Huck, M. Höner, S. Khan, R. Molo, A. Schick, P. Ungelenk DELTA, Dortmund, Germany S. Cramm, L. Plucinski, C.M. Schneider Forschungszentrum Jülich, Peter-Gruenberg-Institut-6, Jülich, Germany S. Döring, L. Plucinski, C.M. Schneider Universität Duisburg-Essen, Duisburg, Germany
	Funding: Work supported by DFG, BMBF, and by the Federal State NRW. The short-pulse facility at the 1.5-GeV synchrotron light source DELTA, operated by the TU Dortmund University, generates coherent VUV and THz radiation by Coherent Harmonic Generation (CHG). Here, a femtosecond laser pulse interacts with an electron bunch in an undulator causing a periodic energy modulation and subsequent micro-bunching, which gives rise to coherent radiation at harmonics of the seed wavelength. Rather than using Ti:Sapphire laser pulses at 795 nm directly, the second harmonic is employed for seeding since 2012. After significant modifications of the seed laser beamline and the dispersive chicane to improve the microbunching, the last commissioning steps include characterization of the CHG radiation and preparing the experimental setup at an existing VUV beamline for time-resolved photoemission spectroscopy. In this paper, the status of the project and recent experimental results are presented.

Paper

Title

Page

Temporal and Spectral Observation of Laser-induced THz Radiation at DELTA

94

P. Ungelenk, H. Huck, M. Huck, M. Höner, S. Khan, R. Molo, A. Schick
DELTA, Dortmund, Germany
N. Hiller, V. Judin
KIT, Karlsruhe, Germany

Funding: Work supported by the DFG, the BMBF, the Federal State NRW, the Initiative and Networking Fund of the Helmholtz Association, and the German Federal Ministry of Education and Research.
Coherent THz pulses caused by a laser-induced density modulation of the electron bunches are routinely produced and observed at DELTA, a 1.5 GeV synchrotron light source operated by the TU Dortmund University. New measurements performed with a fast hot-electron bolometer allow insight into the turn-by-turn evolution of these pulses. Furthermore, first results from a Fourier transform infrared spectrometer, which is currently under commissioning, are presented.

MOPME008

Beam Diagnostics by Using Bunch-by-bunch Feedback Systems at the DELTA Storage Ring

485

M. Höner, H. Huck, M. Huck, S. Khan, R. Molo, A. Schick, P. Ungelenk
DELTA, Dortmund, Germany

Funding: Work supported by BMBF (05K10PEB)
At DELTA, a 1.5-GeV electron storage ring operated by the TU Dortmund University, longitudinal and transverse bunch-by-bunch feedback systems are in use to detect and suppress multi-bunch instabilities. Besides that, the digital feedback systems are excellent diagnostics tools. As an example, by exciting a certain number of bunches within the bunch train, the coupling to the non-excited bunches can be investigated below and above the instability threshold. Other examples include studies of the injection process and monitoring bunch oscillations during sudden beam loss. First experimental results will be presented in this paper.

TUPWO007

Investigation of the Magnetic Chicane of the New Short-Pulse Facility at the DELTA Storage Ring

1889

R. Molo, J.A. Grewe, H. Huck, M. Huck, M. Höner, S. Khan, A. Schick, P. Ungelenk
DELTA, Dortmund, Germany

Funding: Supported by DFG, BMBF, and the Federal State NRW.
The new short-pulse facility at DELTA (a 1.5-GeV synchrotron light source) based on coherent harmonic generation (CHG) utilizes an electromagnetic undulator which can be configured as optical klystron (undulator – chicane – undulator). To optimize the CHG signal, the energy modulation of the electrons in the first undulator and the dispersion of the magnetic chicane (i.e. the R56 matrix element) have to be optimized. Since the R56 value of the present chicane is not sufficient, it is planned to rewire the magnetic coils to create a more efficient chicane. Simulations of the present chicane will be compared to measurements of the R56 matrix element and a new chicane configuration will be presented which increases the R56 value by a factor of ten.

WEPWA005

Experimental Characterization of the Coherent Harmonic Generation Source at the DELTA Storage Ring

2132

M. Huck, H. Huck, M. Höner, S. Khan, R. Molo, A. Schick, P. Ungelenk
DELTA, Dortmund, Germany
S. Cramm, L. Plucinski, C.M. Schneider
Forschungszentrum Jülich, Peter-Gruenberg-Institut-6, Jülich, Germany
S. Döring, L. Plucinski, C.M. Schneider
Universität Duisburg-Essen, Duisburg, Germany

Funding: Work supported by DFG, BMBF, and by the Federal State NRW.
The short-pulse facility at the 1.5-GeV synchrotron light source DELTA, operated by the TU Dortmund University, generates coherent VUV and THz radiation by Coherent Harmonic Generation (CHG). Here, a femtosecond laser pulse interacts with an electron bunch in an undulator causing a periodic energy modulation and subsequent micro-bunching, which gives rise to coherent radiation at harmonics of the seed wavelength. Rather than using Ti:Sapphire laser pulses at 795 nm directly, the second harmonic is employed for seeding since 2012. After significant modifications of the seed laser beamline and the dispersive chicane to improve the microbunching, the last commissioning steps include characterization of the CHG radiation and preparing the experimental setup at an existing VUV beamline for time-resolved photoemission spectroscopy. In this paper, the status of the project and recent experimental results are presented.