Conveners
WG5_Parallel
- Bernhard Schmidt (DESY)
- Olle Lundh (Lund University)
WG5_Parallel
- Olle Lundh (Lund University)
- Bernhard Schmidt (DESY)
WG5_Parallel
- Olle Lundh (Lund University)
- Bernhard Schmidt (DESY)
WG5_Parallel
- Bernhard Schmidt (DESY)
- Olle Lundh (Lund University)
Mr
Omid Zarini
(Helmholtz-Zentrum Dresden-Rossendorf)
25/09/2017, 16:00
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Laser-wakefield accelerators (LWFA) feature electron bunch durations about a few fs. Precise knowledge of the longitudinal profile of such ultra-short electron bunches is essential for the design of future table-top Xray light-sources and remains a big challenge due to the resolution limit of existing diagnostic techniques and also limited reproducibility of electron bunches.
Measurement of...
Ms
Mozhgan Hayati
(University of Bern)
25/09/2017, 16:20
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
We propose a new concept for a femto- to sub-femtosecond resolution electron streaking detector. It is based on a split ring resonator (SRR), which is loaded by a single cycle THz pulse. The methodology relies on a resonant THz sub-wavelength structure irradiated with an intense single cycle THz pulse. The deflecting electrodes and the RF streaking field of a standard streaking device are...
Ms
Maria Katharina Weikum
(DESY / University of Strathclyde)
25/09/2017, 16:40
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
With electron beam durations down to femtoseconds and sub-femtoseconds achievable in current state-of-the-art accelerators, longitudinal bunch length diagnostics with resolution at the attosecond level are required. In this paper, we present such a novel measurement device which combines a high power laser modulator with an RF deflecting cavity in the orthogonal direction. While the laser...
Mr
Daniel Marx
(DESY)
25/09/2017, 17:00
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
A transverse deflecting structure is a well-known device for the characterization of the longitudinal properties of an electron bunch in a linear accelerator. The standard use of such a cavity involves streaking the bunch along a transverse axis and analysing the image on a subsequent screen to find the bunch length and the slice properties along the other transverse axis. A novel X-band...
Fabrizio Giuseppe Bisesto
(LNF)
25/09/2017, 17:15
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (> 100 GV/m), enabling acceleration of electrons to GeV energy in few centimeters. Due to the instabilities occurring during the process, single shot diagnostics are essential to properly characterize it.
In this work, an overview of the single shot...
Prof.
Thomas Feurer
(University of Bern)
25/09/2017, 18:00
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Plasmon- or phonon-polaritons excited at plane or structured interfaces or in in sub-wavelength resonators by strong THz pulses are interesting candidates for miniaturized accelerator components. Often these structures show either electric or magnetic near-field enhancement alleviating the need for a strong driving THz source. Today laser-driven THz sources can produce single-cycle pulses with...
Spencer Gessner
(CERN)
25/09/2017, 18:20
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
The evolution of plasmas on timescales much longer than the beam-plasma interaction time is of interest for potential high repetition rate applications. In the AWAKE experiment, a terawatt-class laser is used to ionize a ten meter-long Rb vapor during or before the transit of a 400 GeV proton beam. The proton beam is modulated by the plasma through a process called the Self-Modulation...
Mr
Manuel Kirchen
(University of Hamburg)
25/09/2017, 18:40
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Plasma-based accelerators offer the possibility to drive future compact light sources and high-energy physics applications. Achieving good beam quality, especially a small beam energy spread, is still one of the major challenges. Here, we propose to use a periodically modulated plasma density to actively shape the longitudinal fields acting on an electron bunch in the linear wakefield regime....
Dr
Erdem Oz
(Max Planck for Physics)
25/09/2017, 19:00
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
The World’s first proton driven plasma wakefield accelerator experiments AWAKE at CERN has started at the end of 2016. For the first stage of the experiments self-modulation-instability (SMI) is studied. SMI develops as the 12 cm long 400 GeV proton bunch traverses the plasma where it gets transversely modulated over 10 meters by the transverse forces in the plasma. In the second phase of the...
Mr
Thomas Audet
(Laboratoire de Physique des Gaz et des Plasmas, CNRS-Université Paris-Sud, 91405 Orsay)
25/09/2017, 19:15
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Laser plasma acceleration (LPA) is a promising scheme for compact high energy accelerators and the multi-staged scheme is actively investigated in relation with several large scale projects such as CILEX / Apollon and EuPRAXIA. However, several issues have to be addressed to optimize electron properties.
In particular, the target density average and its fluctuations are crucial parameters...
Dr
Roxana Tarkeshian
(Universität Bern)
26/09/2017, 16:00
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
We present a novel diagnostics to characterize high brightness electron beams. The technique, based on the tunnel ionization of a neutral gas by the intense (GV/m) self-field of the electron beam, can be used to measure the volumetric charge density of the beam; e. g. to reconstruct pulse durations shorter than few femtoseconds or to measure transverse beam sizes below the micron level. ...
Mr
Maxwell LaBerge
(HZDR/University of Texas at Austin)
26/09/2017, 16:20
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Because of their tiny accelerating cavities, laser-plasma accelerators (LPAs) can produce extremely low-emittance e-beams, but to date the smallest transverse LPA e-beam sizes have been characterized only indirectly inside the LPA by betatron x-ray spectroscopy. Here we report observations of visible optical transition radiation (OTR) imaged from a foil placed immediately (<1mm) outside a...
Mr
Paul Scherkl
(SUPA, University of Strathclyde, and the Cockcroft Institute)
26/09/2017, 16:40
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Advanced particle accelerators and their applications rely on exact synchronization and alignment of laser pulses with respect to charged particle beams. Prominent examples are pump-probe experiments with free electron lasers and plasma photocathode accelerators..
The presentation discusses a novel technique which harnesses enhanced plasma recombination glow from impact ionization from...
Mr
Simon Bohlen
(DESY/University of Hamburg)
26/09/2017, 17:00
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
The results of calibrating three independent charge measurement diagnostics with electron bunches from a laser wakefield accelerator are presented. The detectors used are phosphor screens (type DRZ), an integrated current transformer (ICT/Toroid), and a cavity-based dark current monitor (DaMon). The simultaneous use of all three measurement techniques allowed the cross-calibration of the DRZ,...
Mr
Jan-Hendrik Roeckemann
(DESY)
26/09/2017, 18:00
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Active plasma lenses are a key component for advanced accelerator concepts due to their high, tunable gradients (short focal length), radial symmetry (focusing in both planes) and compact design. A detailed characterization of their properties is inevitable in order to fully decipher and control the relevant plasma processes and bring active plasma lenses up to current accelerator standards in...
Mr
Carl Andreas Lindstrøm
(University of Oslo)
26/09/2017, 18:20
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Future plasma-based accelerators will need strong and compact focusing elements to complement the high gradient acceleration, in particular for beam transport between plasma stages. Using discharge capillary (active) plasma lenses is a promising technology, providing axially symmetric (focusing only) large magnetic field gradients at cm-scale. This is achieved by passing a strong discharge...
Prof.
Roman Walczak
(University of Oxford)
26/09/2017, 18:40
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
It has now been shown experimentally that electrons can be accelerated to 4-GeV energies in a plasma wakefield driven by a single high-intensity laser pulse. However, such laser systems have limited repetition rates and low wall-plug efficiency. An alternative method is to resonantly excite plasma oscillations using a train of laser pulses of lower intensity spaced by the plasma period to...
Mr
Robert Shalloo
(JAI, University of Oxford)
26/09/2017, 19:00
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Design parameters for the next generation of laser plasma accelerators show the need for low density (~1e17cm-3) plasma channels of the order of hundreds of millimetres long with the capability to operate at repetition rates up to 1kHz.
Although gas-filled capillary discharge waveguides have been operated at repetition rates of 1kHz, it is not yet clear if they could guide high-energy laser...
Francesco Filippi
(LNF)
26/09/2017, 19:15
WG5 - High-Gradient Plasma Structures/Advanced Beam Diagnostics
talk
Plasma confinement inside capillaries has been developed in the past years for plasma-based acceleration to ensure a stable and repeatable plasma density distribution during the interaction with either particles or laser beams. In particular, in gas-filled capillaries, the neutral gas is ionized by a discharge current and confined to let it evolves leading to a stable and almost predictable...
