EMP and debris mitigation workshop

Feb 24, 2022, 8:00 AM → Feb 25, 2022, 12:00 PM Europe/Amsterdam

About the workshop

The event is organized in the framework of the IMPULSE project, Task 4.2 (Definition of a standard approach to the target supply and debris shielding) and aims to bring together scientists from ELI pillars, their partners from major European laboratories and users, to debate critical issues on Electromagnetic Pulse (EMP) and debris encountered in high power laser experiments. The meeting is intending to be focused on:

• specific EMP and debris problems encountered in the fs lasermatter interaction experiments,
• the recent experimental and theoretical results on EMP,
• the damage induced by debris,
• current status and implementation of EMP and debris shielding within the ELI facilities and partners: STFC, HZDR and TUD as well as in other high power laser facilities,
• Strategies, requirements and efficient technical solution for mitigation the EMP and debris.

The workshop meeting will be organized by ELI-NP online via Zoom, due to the COVID19 pandemic situation.

Topics:

1. Updates on the experimental and theoretical results on EMP.
2. Strategies, solutions, requirements, open questions for EMP and debris shielding with respect to target types and materials, their geometry (dimension and shape) and laser parameters (energy, contrast, intensity, etc.).

 

Deadline for registration

17 February, 2022

Abstract submission

Abstract submission for EMP and debris mitigation workshop is open until February 17.

Abstracts may be submitted for consideration as an oral contribution.

 

Schedule:

The workshop program will be available soon.

 

Local contacts:

Marius Gugiu: marius.gugiu@eli-np.ro

Mihail Cernaianu: mihail.cernaianu@eli-np.ro

Impulse Task 4.2 participating institutions: ELI-DC, ELI-ALPS, ELI-BEAMS, ELI-NP, ELI-ALSP, HZDR, TUD, STFC

Thursday, February 24

SESSION I: STRATEGIES, SOLUTIONS, REQUIREMENTS, OPEN QUESTIONS FOR EMP AND DEBRIS SHIELDING [ 8:30 - 11:30 CET ]

Convener: Dr. Tomas Lastovicka, Dr. Marius Gugiu

1 Introduction

Speaker: Dr Mihail Cernaianu (ELI-NP)

2 EMP and Debris Mitigation Concepts @ ALI-ALPS

Very high amplitude electromagnetic pulses (EMP) are generated during the interaction of high intense laser pulses with targets. Such huge EMP can interfere or disrupt diagnostics and compromise the reliable operation of the beamlines. On the other hand, such interactions lead to the generation of a notable amount of Debris. Moreover, this introduces huge mitigation challenges for high repetition rate experiments. In this talk, we will outline the current EMP and Debris mitigation being implemented at ELI-ALPS. Furthermore, recent EMP measurements on PW-class systems will be presented.

Speaker: Dr Kwinten Nelissen (ELI ALPS)

3 EMP and Debris Mitigation Challenges in Commissioning Experiments at 1 PW level in ELI-NP

Mihail Cernaianu and Marius Gugiu
on behalf of ELI-NP team

The ELI-NP (Extreme Light Infrastructure - Nuclear Physics) research facility is approaching full operational status. Last year, the commissioning of the 1 PW experimental area has been successfully performed with a TNSA experiment on proton acceleration. In this experiment, the laser beam was focused with a peak intensity of the order of Io > 10^21 Wcm^-2, and interacted with solid targets of various thicknesses and materials. A wide parametric scan was undertaken by shooting on different target materials and thicknesses ranging from hundreds of nm to micrometers, in a configuration without and with a plasma mirror. A wide range of laser and plasma diagnostics were deployed to characterize the laser beam and the by-products of the interaction on a shot-to-shot base. The EMP measurements conducted in parallel allowed a more accurate estimation of the EMP to be generated in high-power femtosecond laser-matter experiments envisaged at this facility, in correlation with the limits of exposure for electronic equipment and personnel. The important approaches, which are considered in the design of experimental instruments, in order to obtain and maintain the overall integrity of electromagnetic shield, will be pointed out. The challenges and different technical implemented solutions will be reported. Other solutions that are under implementation or considered for future experiments will be also discussed.

Speaker: Dr. Mihail Cernaianu, Dr. Marius Gugiu (ELI-NP)

EMP workshop TNSA ELINP_moc_EMP_final.pdf

4 General Atomics Debris Shield Development

GA has served the target fabrication community with custom developmental targets as well as mass-fabricated targets for high rep-rate facilities. GA is now embarking on the fabrication of large (20-50 cm) debris shields to better serve this need in the laser facility community. Technical progress and initial demonstration samples will be presented.

Speaker: Dr Lane Carlson (General Atomics)

5 EMP and Debris Mitigation Strategies at HZDR

In this presentation, we illustrate EMP and debris mitigation strategies implemented at HZDR operated laser facilities.

Speaker: Dr Irene Prencipe (HZDR)

10:30 AM Break

6 ELIMAIA system commissioning 2021/11 - EMP measurement and mitigation

Speaker: Dr Stanislav Stancek (ELI-Beamlines)

EMP_Debris_Stanislav Stancek.pdf

7 On the nature of laser-generated electromagnetic pulse emission and the possible mitigation methods

One of the side effects of high-intensity laser-target interactions under conditions typical for laser-induced proton acceleration is an undesirable strong emission of electromagnetic signals in the MHz to multi-GHz frequency range. The physical origin of these signals is clear, but a quantitative predictive approach is still missing. In our contribution we report on a numerical study of EMP generation, performed with the use of a numerical package allowing for electromagnetic signal computation in the presence of conducting elements in parallel with particle-in-cell modeling of charged particle propagation. We make some educated assumptions on the characteristics of fast electrons escaping from the laser target and we use this as an input for the commercial Computer Simulation Technology Studio Suite package. We then compute the electromagnetic fields in the vicinity of the target and the target holder under conditions corresponding to a real life experiment performed at the 10 TW fs laser in IPPLM. We perform also simulations for some arrangements aimed at mitigation of EMP emission. Results of numerical simulations are confronted with experimental results obtained at the IPPLM facility. Our results should be useful in guiding EMP measurements and mitigation attempts at high-power high-intensity laser facilities.

Speaker: Dr Piotr Raczka (IPPLM)

11:30 AM Break

SESSION II: UPDATES ON THE EXPERIMENTAL AND THEORETICAL RESULTS ON EMP [ 15:00-16:30 CET ]

Convener: Dr Kwinten Nelissen

8 EMP monitoring and debris mitigation in the P3 chamber at ELI Beamlines

In an experimental campaign in December 2021, the HAPLS laser at ELI Beamlines delivered up to 10 J pulses in both single shot and 3.3 Hz regimes. The campaign was used to test various debris protection shields and to monitor laser-plasma intensity levels through EMP measurements. In the contribution, we also summarize EMP effects on electronics used in the P3 experimental chamber.

Speaker: Dr Tomas Lastovicka (ELI Beamlines)

EMP_Debris_Tomas_Lastovicka.pdf

9 Electro-Magnetic Pulse Measurements at the VEGA Laser Facility

We present and compare experimental studies of electromagnetic pulses (EMP) produced by the interaction of relativistic laser pulses at intensities of several 10^20 W/cm^2 with solid density targets. Passive calibrated B-field antennas with large bandwidth from 9 kHz to 400 MHz are used to detect electromagnetic pulses and excited cavity modes triggered by the laser-plasma interaction.
Both high-power 30 fs lasers, VEGA-2 with 200 TW and VEGA-3 with 1 PW, were deployed to discharge targets by hundreds of nano Coulomb. The escaping relativistic electrons trigger successive return current dynamics in the target and strong electromagnetic fields in the interaction chamber.
Building upon the study, we present prospects for a target geometry mitigating EMP and potentially applicable to particle beam collimation.

Speaker: Dr Michael Ehret (CPLU)

EMP_Debris_Michael Ehret.pdf

10 EMP Based Alignment in Laser Based Acceleration Systems

Alignment is a critical issue in laser acceleration techniques. A laser-target system is usually mechanically prealigned and further alignment optimizations are performed by optical methods (use of a test beam, CCD viewing cameras and so on). However, these methods are generally used successfully in low power laser regime. As laser power increases, most existing alignment techniques become inefficient both due to nonlinear behavior occurring in certain physical phenomena and due to electromagnetic pulses (EMPs) produced by the laser-matter interaction, which can cause equipment malfunctions.
Present work proposes a method of alignment in high-power system regime, based on EMP parasitic emissions and presents some results obtained in CETAL-PW laser system.

Speaker: Dr Aurelian Marcu (INFLPR)

Friday, February 25

11 Round table / Open discussion / Conclusions

12 Discussion of points to address for T4.2 Deliverable 4.3 - Reserved for IMPULSE members