M. GANCIU, B. MIHALCEA, M.E. OPRAN,

C. DIPLAȘU, C. TICOS, A. GROZA, C. LUCULESCU, O. STOICAN, A. SURMEIAN

INFLPR MĂGURELE, ROMANIA

B. CRAMARIUC – IT CENTER FOR SCIENCE AND TECHNOLOGY,

BUCHAREST, ROMANIA

R. VASILACHE – CANBERRA PACKARD SRL, BUCHAREST, ROMANIA

O. MARGHITU – INST. OF SPACE SCIENCE, MĂGURELE, ROMANIA

Space radiation environment can lead to extremely harsh operating conditions for on-board electronic box and systems. The characteristics of the radiation environment are highly dependent on the type of mission (date, duration and orbit).

Radiation accelerates the aging of the electronic parts and material and can lead to a degradation of electrical performance; it can also create transient phenomena on parts. Such damage at the part level can induce damage or functional failure at electronic box, subsystem, and system levels.

A rigorous methodology is needed to ensure that the radiation environment does not compromise the functionality and performance of the electronics during the system life. This methodology is called hardness assurance. It consists of those activities undertaken to ensure that the electronic piece parts placed in the space system perform to their design specifications after exposure to the space environment.

Radiation Hardness Assurance (RHA)

Radiation-hardened electronic components are being increasingly used for satellite technology applications → maintenance is not possible in such environments

Satellites (space systems) are vital components for modern technology: defense and customer

purposes, starting with military imaging satellites to consumer communication satellites Legacy systems → form, fit and function equivalents. Maintaining legacy systems running

(operational) is an alternative which leads to budget reduction and adjustment of total costs. Extending the life-time of currently operating satellites

Assessing the threats → The biggest danger for orbiting satellite technology are the Van Allen

radiation belts. Explorer 1 and Explorer 3 satellites confirmed the existence of the belt in early 1958 (James Van Allen team). The trapped radiation was first mapped out by Explorer 4, Pioneer 3 and Luna1.

Radiation hardening : a mandatory condition for space critical applications

VAN ALLEN RADIATION BELTS

Earth's inner radiation belt displays a curiously zebra-esque striped pattern, according to the latest findings from NASA's twin Van Allen Probes

http://vanallenprobes.jhuapl.edu/newscenter/newsArticles/20140319.php

Wave-particle interaction between ULF waves and energetic electrons. The South Atlantic Anomaly (SAA)

SAA leads to an increased flux of energetic particles in

this region and exposes orbiting satellites to higher-than-

usual levels of radiation. The effect is caused by the non-

concentricity of the Earth and its magnetic dipole.

http://www.ask.com/wiki/South_Atlantic_Anomaly

VAN ALLEN RADIATION BELTS PHYSICS 1

Outer electron radiation belt → toroidal shape, produced mainly by inward radial diffusion and local acceleration due to energy transfer from whistler mode plasma waves to radiation belt electrons (their number is affected by collisions with atmospheric neutrals, losses to magnetopause and the outward radial diffusion) . The belt consists of high energy electrons (0.1 – 10 MeV) and ions (energetic protons, α particles and O+ ). Wide population fluctuations as a result of geomagnetic storms triggered mainly by plasma disturbances originating in the Sun

1. Y. Y. Shprits, R. M. Thorne Geophysical Research Lett. (Washington, D.C.) 31 (8): L08805 (2004)

2. R. B. Horne, R. M. Thorne et al, Nature (London) 437 (7056): 227–230 (2005)

Inner radiation belt → high concentrations of electrons in the range of hundreds of keV and energetic protons ( > 100 MeV), trapped by the strong (relative to the outer belts) magnetic fields in the region. Proton energies higher then 50 MeV are the result of beta decay of neutrons ↘ outcome of cosmic ray collisions with upper atmosphere nuclei

3. A. A. Gusev, G. I. Pugacheva, U. B. Jayanthi, N. Schuch, Brazilian J. Phys. 33 (4): 775–781 (2003); http://image.gsfc.nasa.gov/poetry/tour/AAvan.html

Third (transient) radiation belt → ultra-relativistic electrons that move around very quickly. Electrons in this belt subject to phenomena (physics) different from those perceived in other belts

4. D. L. Turner, Y. Shprits, M. Hartinger, V. Angelopoulos, Nature Phys. 8, 208 – 212 (2012)

VAN ALLEN RADIATION BELTS PHYSICS 2

T. Konigstein et al., J. Plasma Physics, 2012, doi: 10.1017/S002377812000153

Van Allen radiation belts represent a major risk for orbiting satellite technology: highly penetrating radiation, which may inflict damage to dedicated electronics equipment embarked onboard

Different ways through which charged particles can wreak havoc on satellite electronics

Proven impact of space weather conditions on satellite communications. High energy electron activity during declining phases of the solar cycle → responsible for amplifier damage and for most of the glitches witnessed between 1996 and 2012.

High-speed eruptions of charged particles from the sun result in satellite failures. Solar flares, coronal mass ejections send highly energized particles towards the Earth. Solar storms disrupt communications systems and damage satellites.

Charged particle accumulate in satellites which causes internal charging that damages satellite amplifiers → design of redundant amplifiers

VAN ALLEN RADIATION BELTS AS MAJOR SATELLITE THREAT

Damages range from mild anomalies to full blown, catastrophic failures

Better understanding of damaging radiation could yield strategies that better safeguard astronauts and

equipment in space

Ultra-relativistic electrons within the Van Allen radiation belts penetrate the protective shielding of

satellites

Expensive state of the art technologies are being developed in agreement with numerical simulations and

testing of elaborate models

Third Van Allen belt presumably established by plasma wave whipping out electrons from the outer belt

Electron response varies according to the nature of space phenomena, while depending of their energies

Objectives

Explaining the origin of high-energy particles and mechanisms which accelerate them to

extremely high speeds , storm dynamics and their interaction with the Van Allen radiation ltsbe

VAN ALLEN RADIATION BELTS AS MAJOR SATELLITE THREATS

Earth geomagnetic field affected by the impact of interplanetary shocks. Storm Sudden Commencement (SSC) → Earth magnetic signal response to interplanetary shocks

It is unclear how these particles are produced and accelerated in the magnetosphere

In the inner magnetosphere, interaction of particles with VLF and ULF waves has been considered. Three mechanisms:

1. Prompt acceleration 2. Local acceleration by VLF waves and diffusive radial transport. Resonant interaction with VLF waves could heat particles for days 3. Diffusive radial transport by ULF waves (excited by solar wind pressure variations) VLF wave-particle interaction considered to be the primary

electron acceleration mechanism (electron resonances in the VLF frequency range)

Solar wind and interplanetary shocks → energy sources for the magnetosphere

Q-G Zong, Y-F Wang, C-J Yuan, B. Yang et al , Chinese Sci. Bull. 56 (12) , 1188-1201 (2011)

“Killer” electrons acceleration mechanisms

o Due to its use on low-Earth orbits, most consumer electronics is less tolerant to radiation

effects, as communication (commercial) satellites are exposed to far less radiation than those

placed on Geostationary orbits

o Sensors with increased ability used to gather satellite data

o Increased data traffic between satellites or back to Earth →need for more powerful algorithms

and more logic in a smaller space, as satellite costs have to be “redimensioned “

o Power issues (solar cells), thermal issues and payload issues (processing large amounts of data

and making decisions or send data to the ground)

o Processing power has to be “adjusted” to data traffic while using as little power as possible →

shrinking of transistor size : 90 nm technology → worsening SNR

o Survival of 90 nm technology to aggressive space environment conditions

o Low voltages susceptible to radiation interference

o New technologies on the consumer market : wide-bandgap technologies

o Radiation effects: total dose, constant bombardment of radiation and low dose rate effects

Radiation-hardened Space Electronics

• RHA consists of all steps performed in order to ensure that all components within a space system perform according to their design specifications after exposure to the space radiation environment

• RHA deals with environment definition, part selection, part testing, spacecraft layout, radiation tolerant design, mission/system/subsystems requirements, mitigation techniques, etc.

• Radiation Hardness Assurance goes beyond the piece part level

Radiation Hardness Assurance (RHA) revisited

Traditional accelerator facilities

The radiation environment used for ground testing should ideally be similar to the natural environment probed

by the satellite

This condition is difficult to achieve by traditional accelerator facilities

Recently, it was suggested that high power lasers (LPA) could be a better alternative for testing applications

The energy spectrum of laser accelerated particles is quite similar to the natural one (exponential energy

distribution), unlike the quasi monoenergetic spectrum of accelerated particle beams in classical accelerators

B. Hidding, T. Königstein, O. Willi, J.B. Rosenzweig, K. Nakajima, and G. Pretzler,

Nucl. Instr. Meth. A, 636 31

State of the art in testing for radiation hardening purposes

Plasma acceleration is a technique for accelerating charged particles, such as electrons,

positrons and ions, using an electric field associated with electron plasma wave or other

high-gradient plasma structures (like shock and sheath fields). The plasma acceleration

structures are created either using ultra-short laser pulses or energetic particle beams that

are matched to the plasma parameters. These techniques offer a way to build high

performance particle accelerators of much smaller size than conventional devices The

basic concepts of plasma acceleration and its possibilities were originally conceived by

Toshiki Tajima and Prof. John M. Dawson of UCLA in 1979.

LASER PLASMA ACCELERATION

Plasma Wakefield Acceleration Mechanism

http://www.aist.go.jp/aist_e/latest_research/2004/20040812/20040812.html

http://silis.phys.strath.ac.uk/

LASER PLASMA ACCELERATION (LPA) FOR OTHER TYPES OF TARGETS

S. Y. Kalmykov et al , New J. Phys. 12 (2010) 045019

http://www.scapa.ac.uk/?page_id=53

Ion acceleration from a laser-solid interaction LPA using a gas cell

nianRoma Patent Application, OSIM, A 8/00 43, 28/08/2013

Method of testing components and complex systems in the pulsed and synchronized fluxes of laser accelerated particles

Two or more pulsed fluxes of particles, that can eventually be associated with the emission of gamma or X ray

radiation

Separate (individual) laser-plasma accelerators, located at various positions and distances with regard to the

system to be tested

The instantaneous intensity of synchronized pulsed fluxes of accelerated particles can largely exceed the one

characteristic to conventional accelerators

Multiple damage and malfunctions induced on specific time periods

Tests of complex systems and computer software which drives them

Synchronized and Pulsed Fluxes consisting of Laser Accelerated Particles

Laser-Plasma Acceleration of Particles for Radiation Hardness Testing (LEOPARD)

Project goals and objectives

The LEOPARD project will establish a Centre of Competences in radiation hardness testing, able to exploit existing laser infrastructures at the Centre for Advanced Laser Technologies (CETAL - 1 PW) and the upcoming ELI-NP (2 X 10 PW) , in the near future, as well as the complementary equipment and expertise of several research groups.

The Centre of Competences will enable proficiency in radiation hardness testing and its applications – based on both laser-plasma acceleration and conventional setups. Moreover, LEOPARD will make possible the development of adapted new calibration and detection systems.

The project will strongly benefit from available competences, as expressed in particular by the recent patent application submitted by the core team.

LEOPARD will address radiation hardness testing for both hardware components and software. Hardware testing is related to the behaviour of components and systems subject to intense radiation fluxes, and implies fundamental research in interaction of radiation with matter, plasma physics, or nuclear physics, as well as applied research – for example to optimize and calibrate the particle fluxes at the target. Software testing on the other hand refers to the programs that control the hardware at various levels, whose built-in redundancy can compensate the hardware faults.

The high-power laser equipment in Magurele will thus become relevant for space applications and make a significant contribution to enhancing the reliability of critical space infrastructure

Short description of the LEOPARD (STAR-ROSA) project

The severe radiation environment of the outer space is a major challenge for satellite equipment, which turns

radiation hardness assurance (RHA) into a key issue when designing and testing spacecraft hardware and

software, able to withstand high levels of irradiation. Space missions require intensive tests towards evaluating

potential radiation damages, then implement appropriate design to prevent these damages while performing

radiation hardness testing of critical components – traditionally performed at large accelerator facilities. As the

energy spectrum of classical accelerators is quite different with respect to the space environment, such tests

are not very relevant for space missions

Project goal

Establish the fact that laser-plasma acceleration of particles represents a modern, effective and consequently

a more appropriate method to perform radiation hardness tests, under similar conditions with

those encountered in the natural environment

Estimated results for the LEOPARD Project

Development and testing of new solid targets for laser-plasma acceleration

Development of adapted new calibration and detection systems

Addressing radiation hardness testing issues for both hardware components and software based on existing cooperations

with the Polytechnical Institute of Bucharest, the Faculty of Automation

Achieving technology transfer through partnership with the industry

Achieving a critical mass of specialists in a high-tech field for fundamental physics, space science and state of the art

technology, while attracting PhD or Post-Doc students which is a key issue

Focus on education and outreach, in order to make information and progress available to the public

Human resources involved

o A core team of skilled researchers from INFLPR and Key experts from Romania and other EU countries,

including ESA (European Space Agency)

Start date of the project / End date of the project: 20.11.2013 / 19.11.2016

The ingWork plan orf LEOPARD project

WP1 → In depth layout of the project strategy, of work and collaboration strategy between the groups which establish the Centre of Competence

WP2 → Training of young researchers with respect to specific project objectives and increasing the work groups skills in using high power lasers for experiments on particle acceleration in plasma, for different types of targets

WP3 → Preliminary tests performed within the frame of the Centre of Competence, aimed towards laser induced acceleration in plasmas which are fitted to study the response of simple and complex systems which undergo interaction with intense radiation flux

WP4 → Study on implementing an innovative multiple irradiation system using pulsed and

synchronized laser accelerated particles, based on the existing facilities at Magurele

Implementation status of LEOPARD project

The technical objectives consist in using the CETAL very high power laser to:

Experimentally demonstrate that high energy electron fluxes can be generated using LPA mechanisms, in a controllable fashion

Investigate the electron plasma regimes depending on the laser pulse duration and laser power. We estimate that bubble plasma regimes are

not appropriate

Explore the use of the CETAL laser for radiation hardness tests and damage studies for hardware and software components intended for

space missions

Demonstrate the feasibility of developing a LPA testing facility in Romania for space radiation studies, with an aim to establish facility to complement

and enhance the ESA RHA programme

Technology Readiness Level (TRL)

Feasibility to generate representative electron spectra up to 10 MeV with an exponential energy distribution → recently demonstrated in the

laboratory [1]

Start TRL → 2

Target TRL after commissioning the new CETAL PW laser facility ↗ 3-4

[1] B. Hidding, T. Konigstein, J. B. Rosenzweig, K. Nakajima and G. Pretzler, Nuclear Instruments and Methods in Physics Research, A636 31-40 (2011)

CETAL PW LASER FACILITY

http://pw.cetal.inflpr.ro

CETAL Petawatt Laser

Built on Ti-Sapphire technology the laser can deliver pulses of 25 J with a duration

of 25 fs at a repetition rate of 0.1 Hz per pulse and wavelength λ = 800 nm.

In the low power mode the laser can operate at an increased repetition rate of 10

Hz, delivering 45 TW per pulse.

The laser beam exiting the compressor has a diameter of 16 cm at FWHM. It is

transported in vacuum by a beam line to the experimental area.

Technical data for the 1 Petawatt laser system

RESULTS

Project with ESA: “Feasibility Study for the Use of the Romanian Cetal

Infrastructure”

Feasibility study aimed at:

1. Electron beam generation, acceleration with electron spectrum up to energies of ~ 100 MeV with

exponential energetic distribution and their characterization

2. Study of generated electron beam interactions with matter

3. Matter characterization and damage assessment

4. Theoretical studies of beam-matter interaction

5. Modelling and simulation of radiation environment and its effects

Results

CETAL laser operational

Beam line system completed

Optical system under testing

Web page created, displayed after kick-off meeting

Commissioning scheduled at 25.05.2014

First experiments scheduled in September 2014

Challenges

o Optical transport system on schedule and laser beam parameters within the interaction chamber should be

consistent with accepted tolerances

o Investigation on electron plasma regimes depending on the laser pulse duration and laser power. The laser pulse

duration should be optimized by intensive tests

o Ability to generate exponential energy distribution electron fluxes

o Test and achieve the most adequate plasma regime which is best fitted to obtain the high energy electron

spectrum with exponential distribution

o Extend pulse duration by means of the laser compressor. Too short laser pulses might yield unwanted energy

distribution

Project contributions to the goal of the STAR Programme

Training young researchers and increasing the competences of the work groups in using high power lasers in experiments on particle

acceleration in plasma

Preliminary tests aimed towards laser induced acceleration in plasmas which are fitted to study the behaviour of simple and complex

systems which undergo interaction with intense radiation fluxes

Key objective → performing preliminary studies with an aim to implement an innovative multiple irradiation system using pulsed and

synchronized laser accelerated particles, based on the existing facilities at Magurele

Valorification of new technologies developed and patented within the framework of the Centre of Competence

Development of numerical simulation methods and new algorithms to illustrate the mechanisms which describe generation and

acceleration of particle flux, under interaction with high power lasers

Training of young researchers in domains considered of utmost importance for ESA and better integration with the ESA agenda

Dissemination activities

First CETAL Petawatt Workshop, November 2013, Magurele, Romania

Romanian Space Week , 12-16 May 2014, Bucharest, Romania

Kick-off Meeting 14.05.2014, INCAS

ERAJUICE - Kick-off Meeting 30.06.2014, NILPRP

Center of Competences

Laser-Plasma Acceleration of Particles for Radiation Hardness Testing (LEOPARD)

Dissemination activities Outreach activities and dissemination to the general public → European Space Expo Craiova, 19 – 27 April

2014 (High Power Laser Applications in Space Industry )