2nd European Advanced Accelerator Concepts Workshop

Session

WG5 - High-gradient plasma structures/Advanced beam diagnostics

14 Sept 2015, 16:00

La Biodola, Isola d'Elba

Conveners

WG5 - High-gradient plasma structures/Advanced beam diagnostics

• Brigitte CROS (LPGP-CNRS-UP11)
• Enrica Chiadroni (LNF)

WG5 - High-gradient plasma structures/Advanced beam diagnostics

• Enrica Chiadroni (LNF)
• Brigitte CROS (LPGP-CNRS-UP11)

WG5 - High-gradient plasma structures/Advanced beam diagnostics

• Enrica Chiadroni (LNF)
• Brigitte CROS (LPGP-CNRS-UP11)

WG5 - High-gradient plasma structures/Advanced beam diagnostics

• Brigitte CROS (LPGP-CNRS-UP11)
• Enrica Chiadroni (LNF)

203. Wakefield electron acceleration in guiding structures under real 3-D nonsymmetrical conditions

Prof. Nikolay Andreev (Joint Institute for High Temperatures of RAS)

14/09/2015, 16:00

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

The nonlinear structures of wakefields exited by the laser and ion bunch drivers are analyzed. The effect of noncollinear electron bunch injection into the wakefields is examined and conditions for an effective trapping of electrons are found. The effect of non-symmetric focusing of the laser radiation into a capillary waveguide and plasma channel on the structure of wakefields and on the...

160. Electron acceleration in deep plasma channels in the Bubble regime

Prof. Alexander Pukhov (uni duesseldorf)

14/09/2015, 16:20

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

We study hollow plasma channels with smooth boundaries for laser-driven electron acceleration in the bubble regime. Contrary to the uniform plasma case, the laser forms no optical shock and no etching at the front. This increases the effective bubble phase velocity and energy gain. The longitudinal field has a plateau that allows for mono-energetic acceleration. We observe as low as 1e−3 r.m.s....

103. Propagation of high-intensity femtosecond laser pulses through ablating metal waveguides

Prof. Konstantin Lotov (Novosibirsk State University)

14/09/2015, 16:40

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

Recent experiments at the Institute of Laser Physics SB RAS are reported. In the experiments, high-intensity, high-contrast (<1e-8), 50 fs laser pulses propagate through 20-mm-long, about 0.05-mm-wide copper waveguides of the triangular cross-section. The triangular shape is chosen for its manufacturability. The transmission through waveguides is 70% for input intensities up to 1e17 W/cm2. The...

84. Continuous-Flow Plasma Target for LWFA: Concept Towards High Repetition Rates

Mr Niels Delbos (University of Hamburg / Center for Free Electron Laser Science)

14/09/2015, 17:00

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

Stable and high-repetition operation of a plasma-target for Laser Wakefield Acceleration is a key element for reliable, accessible and reproducible experiments. Many LWFA experiments rely on targets, which operate with short bursts of gas in order to reduce gas load within the system to a minimum. However, even in burst mode it requires considerable time to reduce the pressure to a level low...

95. Progress of self-modulation experiments with electron and positron beams in plasma wakefield experiments at FACET

Dr Erik Adli (University of Oslo)

14/09/2015, 18:00

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

The E209 experiment at FACET studies the physics of the self-modulation instability in long electron and positron beams in dense plasmas. We report on initial results from experiments in Lithium, Argon and Hydrogen plasmas. We highlight the various experimental challenges, and steps taken to overcome them.

154. Characterisation of Bright X-ray Beams by Powder Diffraction

Mr Gavin Cheung (University of Oxford)

14/09/2015, 18:20

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

It is well known that plasma accelerators can generate bright, energetic X-ray beams via transverse betatron oscillations of the accelerating electron bunch. Many of the applications of betatron radiation require the radiation to be well characterised, but this is difficult owing to large shot-to-shot fluctuations. It is therefore desirable to develop single-shot, non-invasive methods for...

133. Experimental considerations on emittance growth in the Drive Beam recombination at CTF3.

Davide Gamba (CERN; John Adams Institute (JAI))

14/09/2015, 18:40

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

One of the main objective of the CLIC Test Facility (CTF3) at CERN is to demonstrate the two-beam acceleration scheme of CLIC. A key point to ensure stable power production is to obtain a stable and loss-less Drive Beam recombination without spoiling the initial beam quality. The projected emittance of the recombined beam is a clear measurement of the quality of the full process: orbit and...

200. Inverse Compton Scattering as a diagnostic of electron beams

Dr Matthew Streeter (DESY)

14/09/2015, 19:00

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

The interaction of an intense laser pulse with a relativistic electron beam results in a burst of highly energetic photons, via the Inverse Compton Scattering (ICS) process. For a GeV electron beam, photons are generated with energies in excess of 10 MeV, far exceeding the energies possible from magnetic undulators. Characterizing such a photon source presents a real challenge for diagnostic...

91. Laser-ionized plasma source for plasma wakefield accelerators

Dr Erdem Oz (Max Planck for Physics)

15/09/2015, 15:00

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

In 2016, AWAKE will be the first experiment to use a high energy, 400 GeV, CERN proton bunch to drive a plasma wakefield. AWAKE requires a unique plasma source. It is a 10 meter long, 2 mm diameter, laser-ionized Rb plasma with a density range of 10^14 to 10^15 cm^-3 . Plasma density variations as small as 0.2 % can have a detrimental effect on the acceleration of the injected electron bunch...

165. Influence of realistic plasma density profile on ionization-induced electron injection driven by laser wakefield

Mr Thomas Audet (Laboratoire de physique des Gazs e des Plasmas, CNRS UMR - Université Paris Sud)

15/09/2015, 15:20

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

Several important issues have to be addressed to optimize a laser plasma accelerator (LPA) for specific applications. In particular, for high energy physics, a multi-staged scheme consisting of one injector and several LPA stages connected by transmission lines appears most promising. In the frame of the CILEX project, multi-stage experiments are planned with the multi-PW facility APOLLON....

205. Spectroscopic determination of electron density and species distribution

Dr Lucas Schaper (University Hamburg / DESY)

15/09/2015, 15:40

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

For particle acceleration in plasmas one of the key issues for stable and reproducible beams is control over and knowledge of the background plasma parameters. Sophisticated electron injection and laser beam transport mechanisms require not only specific plasma parameters but also e.g. a longitudinal and transverse density profile. In addition the species distribution and ionisation- and...

41. Opto-acoustic measurements of the plasma density within a gas-filled capillary plasma source

Dr Angelo Biagioni (LNF)

15/09/2015, 16:00

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

Plasma density represents a very important parameter for both laser wakefield acceleration and plasma wakefield acceleration, which use a gas-filled capillary plasma source. Several techniques can be used to measure the plasma density within a capillary discharge, which are mainly based on optical diagnostic methods, as an example the well-known spectroscopic method using the Stark broadening...

195. Bunch Profile Reconstruction and Evolution of Laser-Wakefield accelerated Electron Bunches by Single-Shot Measurement of Coherent Transition Radiation

Mr Matthias Heigoldt (Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching, Germany)

15/09/2015, 16:30

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

A unique property of laser-wakefield accelerated electron bunches is their ultra-short duration, resulting in peak currents in the kA range, which may benefit future applications such as laboratory scale X-ray sources or ultrafast time resolved measurements. We present single-shot, high-resolution measurements of the longitudinal bunch profile based on detection of coherent transition...

114. Broadband (UV - mid-IR) spectrometer for single-shot femtosecond electron bunch measurement

Mr Omid Zarini (Helmholtz-Zentrum Dresden-Rossendorf)

15/09/2015, 16:50

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

Laser-wakefield accelerators (LWFA) feature electron bunch durations ranging from several fs to tens of fs. Precise knowledge of the longitudinal profile of such fS electron bunches is essential for the design of future table-top Xray sources and remains a big challenge due to the resolution limit of existing diagnostic techniques. Measurement of broadband coherent and incoherent transition...

82. Longitudinal phase space diagnostic for ultrashort bunches

Irene Dornmair (University of Hamburg)

15/09/2015, 17:10

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

Ultrashort electron bunches of few femtoseconds length are highly desirable for a large number of applications such as ultrafast electron diffraction, free-electron lasers or for external injection into plasma wakefields. As the plasma wavelength determines the length scale in plasma accelerators, also the bunches produced by this technique intrinsically are very short. A precise knowledge of...

10. Synchronization of ebeam and laser beam in 'Trojan horse' plasma wakefield experiment

Mr Yunfeng Xi (UCLA)

15/09/2015, 18:00

WG5 - High-gradient plasma structures/Advanced beam diagnostics

talk

We observed Electro_Optic Sampling(EOS) signals on ZnTe and GaP with different thicknesses. The critical step for "Trojan horse" plasma wakefield acceleration experiment (E210) in FACET is to synchronize electron beam and laser beam at hundreds of femtosecond level to guarantee laser is injected into plasma bubble generated by driver bunch. EOS is a reliable technique to synchronize beams and...