9th Geant4 Space Users' Workshop

4 Mar 2013, 08:00 → 6 Mar 2013, 18:00 Europe/Amsterdam

Barcelona

Giovanni Santin (ESA), José Manuel Quesada (University of Sevilla), Makoto ASAI (SLAC), Miguel Ullan (Centro Nacional de Microelectronica (IMB-CNM, CSIC)), Petteri Nieminen (ESA), Sergio Ibarmia (INTA)

Geant4 Space Users' Workshop –G4SUW– is focused on new results on space radiation interaction with components, sensors and shielding analysis, as well as on Geant4-based tools and developments applicable to space missions. G4SUW will be held on Bacelona, Spain, during 4, 5 and 6 of March 2013. The Geant4 particle transport toolkit is jointly developed by a world-wide Collaboration and is intended for a wide range of applications in HEP, medical field, and space physics and engineering. In recent years, space and astrophysics has become a significant user category, with applications ranging from instrument and detector response verification to space radiation shielding optimization, component effects, support of scientific studies, and analysis of biological effects.

Monday, 4 March

08:00 → 09:00 Workshop registration

09:00 → 11:05 Opening and general status report

09:00 Welcome and Opening Address

Speaker: Mr Sergio Ibarmia (INTA)

09:10 CNM-IMB Opening Presentation

Speaker: Dr Miguel Ullan (Centro Nacional de Microelectronica (IMB-CNM, CSIC))

Slides Ullan_IMB-CNM-CSIC.ppt

09:30 Geant4 at NASA

Speaker: Shawn Kang (Jet Propulsion Laboratory)

09:55 Geant4 at ESA

Speaker: Mr Petteri Nieminen (ESA)

Slides ESA_Geant4_RD_activities_2013.pdf

10:20 Geant4 at JAXA

Speaker: Dr Masanobu Ozaki (JAXA)

Slides Ozaki_Geant4_at_JAXA_2013.pdf

10:45 Geant4 at INTA

Speaker: Mr Sergio Ibarmia (INTA)

11:05 → 11:20 Coffee Break

11:20 → 12:40 Space missions, instruments & detectors I

11:20 Simulation of the GAMMA-400 instrument with Geant4

GAMMA-400 is a space mission which will be configured as a dual experiment, dedicated to the study of both CRs and gamma rays with a state-of-the-art imaging Silicon Tracker and a very deep Calorimeter. It will be able to study electrons, protons and nuclei with energy up to knee and gamma rays in the energy range 30 MeV - 1 TeV. The Montecarlo simulation, based on the Geant4 simulation toolkit, and the event reconstruction are handled by a modular, flexible, very little geometry dependent, easy to expand framework. The Geant4 General Particle Source module is used to simulate both the incoming radiation as well as the cosmic rays background along the foreseen satellite orbit. The simulated satellite geometry comprises a modular structure with the proper inclusion of support structures and dead areas between the detectors. Every part of the satellite is defined in a different and independent file making it easier to change each part of a detector without affecting the whole simulation. The most recent version of the framework includes out-of-tree geometries, a built-in acceptance check and other particle generators.

Speaker: Paolo Cumani (University of Trieste - INFN)

Slides Cumani_G4Workshop.pdf (Protected)

11:40 Radiation modeling of the Particle Environment Package (PEP) for the JUICE mission

Particle Environment Package (PEP) is a particle instrument being proposed for the ESA JUICE mission (Jupiter Icy Moons Explorer) aiming to conduct plasma and neutral gas measurements in the harsh radiation environment of Jupiter. In connection with the JUICE payload Announce of Opportunity extensive radiation analysis of the PEP sensors was performed using GRAS (Geant4 Radiation Analysis for Space), SSAT (Sectoring Shielding Analysis Tool) and others tool available through the SPENVIS interface. Most of the simulation work was performed on small and large scale cluster computation facilities. This presentation describes the simulation infrastructure, methods and some of the result from this analysis work.

Speaker: Mr Stefan Karlsson (Swedish Institute of Space Physics)

12:00 Geant4 Simulations of Space Radiation Sensors at The Aerospace Corporation

Geant4 is a vital tool for understanding and calibrating the response of space-borne radiation sensors at The Aerospace Corporation. For the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) sensor aboard the Lunar Reconnaissance Orbiter (LRO), we have found Geant4 to be particularly critical in modeling the effects of delta rays (energetic secondary or "knock-on" electrons), which are generated in the large amount of inert material (A-150 Tissue Equivalent Plastic) in the detector stack and which cause significant out-of-aperture sensor response. We have also used it to calculate the distribution of secondary particles coming up to the spacecraft from galactic cosmic ray (GCR) interactions with the moon's surface. The Relativistic Proton Spectrometer (RPS) aboard the Van Allen Probes uses a combination of silicon solid-state detectors and a Cherenkov radiator to make energy-resolved measurements of relativistic protons among the GCRs and in the heart of the inner Van Allen belt. We have particularly used Geant4 to hone our understanding of the behavior (Cherenkov light production, scintillation, internal reflection, etc.) of the Cherenkov optical subsystem; the code also proved crucial to our understanding of the laboratory environment when testing at the TRIUMF particle accelerator in British Columbia. Finally, we will discuss work in progress to model the detailed response of the Magnetic Electron Ion Spectrometer (MagEIS) sensor heads aboard the Van Allen Probes. These are a set of magnetic electron spectrometers, using a combination of rigidity filtering and pulse-height analysis to reject background events and obtain a clean signal in the intense electron environment encountered in the active outer Van Allen belt.

Speaker: Dr Mark Looper (The Aerospace Corporation)

Slides Looper_Geant4_at_Aerospace.pdf

12:20 ASTRO-H Monte Carlo Simulation framework

ASTRO-H is next Japanese X-ray astronomy observatory satellite scheduled to be launched in 2015. The orbit is LEO passing through the SAA several times a day, and scientific instruments have sensitivity for not only X-rays but also charged particles. The simulations of detector responses for such incidents and secondaries due to in-orbit activation are thus required forvscientific success, and we are developing Geant4 based Monte Carlo simulator. The simulator include not only the scientific detectors but also full geometry of the satellite. In addition to the geometry, this also has celestial X-ray source, background charged particle generator and detector output parts. The simulator will be supplied to science working group and used for pre-launch background estimation. For the background simulation, activation study has an important role. We have investigated several physics processes for CdTe detecter beam experiments, and had quite good results especially for continuum level representation. This should help to make better in-orbit BGD prediction.

Speaker: Dr Masanobu Ozaki (JAXA)

Slides Ozaki_ASTRO-H_SF_G4SUW2013.pdf

12:40 → 14:20 Lunch break

14:20 → 15:20 Space missions, instruments & detectors II

14:20 Radiation noise modelling and mitigation techniques for low-energy particle sensors in planetary radiation belts

Radiation noise and Total Ionizing Dose (TID) are very serious issues for any instrument proposed to missions that operate in intense radiation environments like JUICE or RBSP. Here we discuss issues and mitigation techniques related to penetrating particle background noise in particle sensors with illustrations taken from real spacecraft measurements. Whereas passive shielding can efficiently reduce TID and protect sensor subsystems (electronics) it cannot alone reduce the background noise to the low level required to fulfil ambitious science objectives. We will illustrate how the combination of both passive multi-layered shielding and active shielding techniques can achieve the desired goal. We will show some general results from our in-house GEANT-4 simulations as well as our laboratory tests and validation of shielded and unshielded detector’s response in relevant high-energy electron environments that validate this approach.

Speaker: Dr Nicolas ANDRE (IRAP/CNRS)

Slides Andre_Noise_Barcelona13_public.pdf

14:40 Experimental Verification of the Soft Proton Small Angle Reflection Process on X-Ray Mirror Shells

In this paper a setup is described, that will be used for an experimental verification of the small angle scattering rate of soft protons (~100 keV - 1 MeV) off of mirror shells of space telescopes with focusing optics. On existing missions (e.g. Chandra, XMM-Newton), the measured rate is a factor 3-4 higher than the predictions using multiple Rutherford scattering suggest. Two physical processes are promising to explain this discrepancy. The setup described will be capable to distinguish between these models. The results can be used to refine and tune simulation codes, which would enhance the precision of soft proton background and damage studies for future X-ray observatories.

Speaker: Mr Sebastian Diebold (Kepler Center for Astro and Particle Physics, University of Tübingen)

Slides Diebold_G4SUW_Mirror_Scattering_Setup.pdf

15:00 Geant4-based simulations of microdosimetric data for high charge and energy particles

The exposure to high charge and energy (HZE) particles is one of major concerns for humans during their missions in space. Microdosimetry is a valuable tool for characterization of radiation quality. Measurements with Tissue-Equivalent Proportional Counters (TEPC) have been performed for several years in space for investigation of solar particle events and galactic cosmic-rays. The response functions of these devices are analysed using accelerators in ground-base facilities. Monte Carlo simulation is an alternative option for design of new detectors and investigation of radiation effects. In this study we apply the Geant4-based application MCHIT (Monte Carlo model for Heavy-Ion Therapy) [1] to simulate several sets of microdosimetric data obtained with walled [2-5] and wall-less [6] TEPCs. MCHIT/Geant4 is able to reproduce in general the response functions and microdosimetric parameters for nuclear beams from H to Fe with energies of 80-1000 MeV/nucleon. MCHIT/Geant4 can be applied for investigation of radiation effects and characterization of TEPCs in space research. [1] L. Burigo et al., http://arxiv.org/abs/1211.3648 physics.med-ph] [2] B.B. Gersey et al., Radiat. Res. 157 (2002) 350 [3] S.B. Guetersloh et al., Radiat. Res. 161 (2004) 64 [4] P.J. Taddei et al., Radiat. Meas. 41 (2006) 1227 [5] G. Martino et al., Phys. Med. Biol. 55 (2010) 3441 [6] S. Tsuda et al., J. Radiat. Res. 53 (2012) 264

Speaker: Mr Lucas Burigo (Frankfurt Institute for Advanced Studies, Johann Wolfgang Goethe University)

Slides Burigo_9thG4SUW.pdf

15:20 → 15:45 Coffee break

15:45 → 17:20 Planetary environments and ground effects

15:45 LIP Planetary Environment Tools

Speaker: Dr Patrícia Gonçalves (LIP - Laboratório de Instrumentação e Física Experimental de Partículas)

Slides LIPG4PlanetaryRadiationModels.pdf

16:10 Modelling the Jupiter system radiation environment and its effects

The Jovian radiation environment presents a severe threat to spacecraft operation due to the large magnetic field of Jupiter allowing it to stably trap charged particles, especially electrons, at higher energies and over greater distances than found in Earth’s Van Allen belts. As part of the ESA JUICE mission, an assessment is on-going into the different hardening and alternative radiation mitigation strategies which may be implemented to reduce the threat from ionising and non-ionising cumulative dose, and spacecraft charging. In this paper we summarise the studies and SPENVIS- and Geant4-based software tools developed and being applied as part of the ESA JORE2M2 and GREET Projects to predict the radiation environment around Europa, Ganymede and Callisto, and to assess the performance of shielding against that environment.

Speaker: Dr Pete Truscott (Kallisto Consultancy Ltd)

16:35 Calculation of the effects of the cosmic-ray induced neutrons at different altitudes on highly integrated microelectronics

High-energy neutrons are produced by primary cosmic ray interactions with atoms in the atmosphere through spallation reactions and intranuclear cascade processes. These neutrons can produce secondary neutrons and also undergo moderation due to atmospheric interactions, resulting in a wide energy spectrum, which ranges from thermal energies (0.025 eV) to energies of several hundreds of MeV. The result is the cosmic-ray induced neutron (CRIN) spectrum. Neutron effects on microelectronics is a growing field due to concerns related about the effects of the CRIN on high integrated microelectronics onboard aircrafts. This work presents a Geant4 application for the calculation of the CRIN effects at different altitudes on highly integrated microelectronics, specifically on a AMISC5 flip-flop target, which has been implemented as a CAD model, imported to GEANT4 by means of GDML.

Speaker: Mr Maurício Tizziani Pazianotto (Instituto Tecnológico de Aeronáutica - ITA, Sao José dos Campos, Brazil)

Slides Pazianotto_MT_4_2013.pdf

17:00 GEANT4 simulations for the Castilla La Mancha Neutron Monitor (CalMaNM)

Castilla-La Mancha Neutron Monitor (CaLMa) is the first installed in Spain and has as mission the continuous measurement of the extra-terrestrial radiation that reaches the ground. Is integrated into the neutron monitors network NMDB (Neutron Monitor Database). A neutron monitor measures the intensity variation of cosmic rays, monitoring solar activity continuously at energy between 1 and 20 GeV. The CaLMa detector is based on 15 counter tubes, filled with 10BF3 at a pressure of 200 mm Hg. Three of them are standard well-known BP28 Chalk River tubes from the Observatoire Midi Pyrénées and the others twelve are new LND 2061 model. Guadalajara (40º37′N, 3º9′W) is located 55 km away from Madrid at 721 m above sea level. The vertical cut off rigidity is about 6.95 GV, which roughly implies that primary particles with energies above 6.07 GeV/uma could be able to reach the monitor. CaLMa is partially operative from October 2011. GEANT4 simulations are being developed to get a detailed knowledge of CaLMa response functions to different incident particle populations. We present the preliminary results of the response of CaLMa using Monte-Carlo simulations based on GEANT 4.

Speaker: Mr Andres Russu (Space and Research Group of University of Alcala (SRG-UAH) | Science and Technology Park of Guadalajara | Spain)

Slides Russu_G4SUWS_SRG_v1.0.pdf

Tuesday, 5 March

09:00 → 10:40 Tools and interfaces

09:00 SPENVIS Interface to Geant4-based tools

By now, the importance of Geant4 models in the planning of space and planetary exploration missions is well established. Their applications range from instrument and detector response verification, space radiation shielding optimisation, component effects, support of scientific studies to the analysis of biological effects and astronaut radiation hazards. For the last years, the web-based ESA Space Environment Information System (SPENVIS, www.spenvis.oma.be) has been providing an interface to various Geant4-based tools covering all the above applications. The Geant4 applications available in SPENVIS are GRAS (3D radiation analysis), MULASSIS (1D radiation analysis), GEMAT (microdosimetry), SSAT (shielding distribution), MAGNETOCOSMICS (cosmic ray rigidity), PLANETOCOSMICS (cosmic ray showers), MC-SCREAM (NIEL effects in solar cells), MEREM (Martian radiation environment) and JOREM (Jovian radiation environment). Some of the interfaces have been implemented by third parties. As support to these interfaces, SPENVIS includes a GDML pre-processor, a material definition module and a geometry definition tool. The latter is a JAVA application that allows one to define complex geometry using spheres, cylinders, and boxes, and generating a GDML file. The GDML pre-processor is a PHP application extracting useful metadata that are used by the SPENVIS interface to GRAS. We provide a general overview of the Geant4 model interface in SPENVIS and demonstrate its advantages for the user e.g. no prior knowledge of Geant4 macro syntax is required. Special attention is given to our interaction with the user community and the model developers. We show how user feedback can lead to some important model improvements. Finally, the latest progress is presented with a special attention to the Next Generation SPENVIS (SPENVIS-NG) that is currently under development. This work is supported by ESTEC contracts No. 19786/05/NL/GLC/jk and 4000104812.

Speaker: Dr Neophytos Messios (BIRA-IASB)

Slides Messios_G4SUW9_SPENVIS_interface_to_Geant4-based_tools.pdf

09:20 A Three-Dimensional Simulator for Internal-Charging Effect

In this abstract, we report a three-dimensional simulator for the internal charging effect. The simulator is developed according to the requirements and technical specifications designed by the CSSC. It uses Geant4 for electron transport calculation, and a 3D PDE solver for charge transport and electrical field calculation. Preliminary result from the solver is presented, with current development efforts outlined.

Speaker: Dr Chen Shen (Ke Jing Da Electronics Ltd)

Slides Shen_G4SUW2013_IDC.pdf

09:40 Geant4 tools and interfaces from ELSHIELD project

In the framework of the ESA funded project "Energetic Electron Shielding, Charging and Radiation Effects (ELSHIELD)", a series of activities were performed to improve exiting Geant4 capabilities and develop new tools and interfaces, all of them related to the estimation of the impact of energetic electrons on space systems. The resulting improvements from these Geant4 activities will be presented, including new EM models, already available at latest Geant4 releases, and their comparison with experimental data, new interface commands for simulation biasing, scoring capabilities in complex meshed geometries and automated shielding analysis tools based on the combination of Geant4 and Genetic Algorithm techniques.

Speaker: Mr Sergio Ibarmia (INTA)

Slides ibarmia_ELSHIELD_G4SUWS_2013.pdf

10:00 An Introduction of the REST-SIM Simulation Framework

REST-SIM is a software simulation framework bringing together mission orbit and space environment specification, spacecraft and payload geometry definition, radiation transport simulation and radiation effects analysis. It has been developed to support the development and execution of ESA’s Cosmic Vision Missions. The framework can be used throughout a whole mission life cycle, starting from pre-flight design and analysis, to testing and calibrations, science operations, and flight data analyses. This talk will give a summary the main capabilities of the REST-SIM framework and the work performed under the ESA REST-SIM project.

Speaker: Dr Fan Lei (RadMod Research)

Slides Lei_REST_SIM_FW_G4SUWS2013.pdf

10:20 Review of Reverse/Adjoint Monte Carlo mode in Geant4

Monte Carlo code as Geant4 in their forward unbiased simulation mode are the most precise for computing the radiation effects in space components of payloads and spacecraft. However it takes most of the time a huge amount of computing time to achieve a good statistical precision of the simulation results, as the components where the dose is computed are very small compared to the entire size of the geometry. To decrease this computing time efficiently without loosing in the correctness of the simulation results different biasing techniques may be used. The biasing technique that adapts probably the best to the case of a tiny sensitive component in a large geometry and within an extensive external source of particles, is the reverse (also called adjoint) Monte Carlo technique. In this simulation mode adjoint particles (e-, gamma, protons,..) are generated on the sensitive component and are tracked backward till the external source. During this backward tracking, physical processes are also applied but in a reverse mode where the projectile and products exchange their role. These reverse processes keep the same differential cross sections but the integral cross section is obtained by integrating over the energy of the product. In order to keep the same statistical significance of a reverse track compared to an equivalent forward track, weight correction needs to be applied at the occurrence of any reverse processes as well as along the transport of the particles. The Reverse Monte Carlo technique is available in geant4 since the release 4.9.3 for most of electromagnetic processes. While it has been shown to work well for the examples provided inside Geant4, recently in the frame of the preparation of the Juice mission significant discrepancies between the reverse and forward mode have been reported. Moreover for some materials the occurrence of statistical peak in the computed dose lead to a significant increase of the simulation time. A review of the Geant4 reverse Monte Carlo mode inside Geant4 has been performed in order to identify the reason for these problems. In this paper we report on these tests, present some modifications that have been already brought to the code and discuss further possible modifications.

Speaker: Mr Laurent Desorgher Desorgher (Paul Scherrer Institut)

Slides Desorgher_Geant4ReverseMC_G4_9thSUW.pdf

10:40 → 11:00 Coffee break

11:00 → 12:40 SEE simulation I: Fundamentals

11:10 The Geant4-DNA project: overview and status

Being able to understand and simulate adverse effects of ionizing radiation at the cellular and sub-cellular scale remains a challenge of today’s radiobiology research. The presented project, named “Geant4-DNA” [http://geant4-dna.org], was initiated by the European Space Agency. Its aim is to develop an experimentally validated simulation platform for modelling DNA damage induced by ionizing radiation. This is an ambitious work of highly interdisciplinary nature, involving several fields (elementary particle physics, chemistry, molecular and cellular biology, and computing science). The platform is based on the general-purpose and open-source “Geant4” Monte Carlo simulation toolkit, and benefits from the toolkit’s full transparency and free availability. This project develops specific functionalities in Geant4 i) The modelling of elementary physical interactions between ionizing particles and biological media (liquid water and DNA), during the so-called “physical” stage. The user can specify in a dedicated “physics list” class the particles and the corresponding physical processes these particles are sensitive to. Very recently, new models have been developed for the transport of proton and hydrogen in DNA material. ii) The modelling of the “physico-chemical and chemical” stages corresponding to the production, the diffusion and the chemical reactions occurring between oxidative radical species. During the “physico-chemical” stage, the water molecules that have been excited and ionized during the physics stage may de-excite and dissociate into molecular radical species. In the “chemical stage”, these radicals may eventually react among themselves or with the DNA molecule. The implementation of reactive radical species in the Geant4 toolkit is currently in progress. iii) The modelling of a “geometrical” stage where the two above stages are combined with a geometrical description of biological targets (such as chromatin segments, cell nuclei…). The Geant4-DNA physics processes and models are fully integrated into the Geant4 toolkit and can be combined with Geant4 geometry modelling capabilities. In particular, it becomes possible to implement the geometry of biological targets with a high resolution at the cellular scale and fully track particles within these geometries. An overview of the developments undertaken by the Geant4-DNA collaboration including a description of software already available for download will be presented as well as future perspectives.

Speaker: Dr Sebastien Incerti (CNRS)

11:35 The MuElec extension for microdosimetry in silicon

The Geant4-MuElec extension, developed by CEA, aims at modeling the effect of ionizing radiation in highly integrated microelectronic components. It describes the transport and generation of very low energy electrons (down to 16.7 eV) by incident electron, proton and heavy ions in silicon. This presentation will give a brief overview of the context motivating this effort and of the theory used to develop this extension. Validation results will be presented, along with an application case to the simulation of proton and heavy ion tracks. Perspectives on future developments will finally be exposed.

Speaker: Dr Melanie Raine (CEA)

Slides Raine_G4SUW_050313.pdf

12:00 Geant4 + TCAD. An application example

Speaker: Dr Miguel Antonio Cortes-Giraldo (Universidad de Sevilla)

Slides Cortes-Giraldo_G4SUW2013_talk.pdf

12:40 → 14:00 Lunch break

14:00 → 15:15 SEE simulation II: Tools and integrated solutions I

14:00 MRED and the CRÈME-MC Web Site

Microelectronic devices are sensitive to ionizing radiation, and with the scaling of devices to ever-smaller dimensions, they are increasingly vulnerable to single event effects. Single event effects are transient errors in active devices — usually although not exclusively in digital circuits — that are caused by the interaction of ionizing particles with the device materials. This presentation will describe the program MRED, a Geant4-based Monte Carlo engine for predicting the rate of single event effects from knowledge of radiation environments and device structure. The approach embodied in MRED combines detailed physical modeling of discrete radiation events, semiconductor device simulation to estimate charge transport and collection, and circuit simulation to determine the macroscopic electrical effects of the collected charge. Details of the Monte Carlo simulation will be presented, and a mathematical analysis that establishes its relationship to earlier single event rate prediction methods will be discussed. The relationship between MRED and the publicly available web site CRÈME-MC will be described.

Speaker: Dr Robert Weller (ISDE/Vanderbilt University)

Slides Weller-G4SUW-2013-Web-Version.pdf (Protected)

14:25 Applications of MRED for Predicting Single Event Effects

MRED (Monte Carlo Radiative Energy Deposition) is Vanderbilt University’s Geant4 application for simulating radiation events in semiconductors. Geant4 is comprised of the best available computational physics models for the transport of radiation through matter. Geant4 is a library of c++ routines for describing radiation interaction with matter assembled by a large and diverse international collaboration. MRED includes a model developed by researchers at Vanderbilt University for screened Coulomb scattering of ions (currently available in the latest Geant4 release), tetrahedral geometric objects, a cross section biasing and track weighting technique for variance reduction, and a number of additional features relevant to semiconductor device applications. The Geant4 libraries contain alternative models for many physical processes, which differ in levels of detail and accuracy. Generally, MRED is structured so that all physics relevant for radiation effects applications are available and selectable at run time. The underlying physical mechanisms for Single Event Effect (SEE) response are: 1) ionizing radiation-induced energy deposition within the device, 2) initial electron-hole pair generation 3) the transport of the charge carriers through the semiconductor device and 4) the response of the device and circuit to the electron-hole pair distribution and subsequent transport. Each of these occur on a different time scale and they are often assumed to be sequential, i.e., energy deposition determines the initial electron-hole pair generation, which in-turn impacts device and circuit response. In this discuss the current application of MRED that are intended to address emerging technology issues as they relate to the mechanisms listed above.

Speaker: Dr Robert Reed (ISDE/Vanderbilt University)

15:15 → 15:35 Coffee break

15:35 → 16:50 SEE simulation III: Tools and integrated solutions II

15:35 A Framework for Fully-Physical Simulation of SEU and Its Applications

In this abstract, we report “RunSEU”, a fully-physical simulation framework for evaluating the SEU cross-section of CMOS circuits. Applications on the analysis of COTS chips are presented. Its limitations in engineering applications such as in-orbit SEU rate prediction or failure mode analysis, and the extensions required in those cases are discussed.

Speaker: Dr Chen Shen (Cogenda Pte Ltd)

Slides Shen_SEU_g4suw2013.pdf

16:00 Geant4 and MINIMOS-NT-based device physics simulation framework for deep sub-micron CMOS radiation effects analysis

The trends in modern CMOS microelectronics technology towards ever smaller feature sizes and more complex geometries containing many different materials has made it increasingly difficult to define appropriate models to treat radiation effects phenomena, especially single event effects. The ESA-funded DESMICREX Project is aimed at developing a system of state-of-the-art simulation software tools within a coherent framework to model radiation effects in deep sub-micron CMOS technologies. The principal tools of the software system comprise Geant4, the MINIMOS-NT device physics simulator, and the GTS Framework. This presentation gives a review of the models and development work undertaken within this on-going project.

Speaker: Dr Pete Truscott (Kallisto Consultancy Ltd)

16:25 CODES

CODES (COmponent DEgradation Simulation) is an ESA GEANT4 based top level engineering to predict Single Event Effects in EEE devices. It consists of different GEANT4 modules with a user friendly web-based interface. The different modules consist of device geometry definition (including packaging and shielding), device sensitivity interpretation based on experimental test data and data analysis. CODES performance and inter-modular communication is assured by a pre-processor using TPC communication protocol. The web interface is deployed in a PHP server. All the models and the web-based inside is able to define the device geometry based on user defined parameters, such as dimensions, shielding layer and active and non active volumes.

Speaker: Ms Ana Keating (LIP/ESA)

Slides Keating_CODES_05032013.pdf

17:45 → 20:30 Guided tour to Barcelona (TBC)

On tuesday evening, a guided visit to some of the most impressive places in Barcelona is scheduled, including from the medieval town (Gothic quarter) to the impressive Casa Batlló and La Pedrera, two examples of the modernista achitecture of Antoni Gaudi

20:30 → 22:30 Workshop Dinner

After the guided visit, we will enjoy a gastronomical experience at LOIDI, a restaurant inspired in the awarded cuisine from the three-Michelin-star Chef Martin Berasategui, where the traditional ingredients meet the most innovative techniques. A perfect example of the revolutionary and state-of-the-art Spanish cuisine.

LOIDI web site:
http://www.condesdebarcelona.com/en/loidi/

Wednesday, 6 March

09:00 → 10:40 Physics processes

09:00 Crystal physics and phonon transport in Geant4

We present an implementation of crystal lattices and phonon transport using the Geant4 toolkit. We discuss basic phonon transport physics as and detailed implementation methods within Geant4 as well as results of our verification and validation effort. The code discussed is capable of tracking acoustic phonons in arbitrary cryogenic crystals, as well as simulate isotope scattering, mode mixing and anharmonic down conversion processes. The physics processes presented are implemented as an extended example available with Geant4 v9.6.

Speaker: Dr Daniel Brandt (KIPAC, SLAC National Accelerator Lab, Stanford)

Slides Brandt_CMPPhonons_G4SUW2013.pdf

09:20 Total and partial fragmentation cross-section of 500 MeV/nucleon carbon ions on different target materials

The nuclear interaction mechanism of carbon ions with nuclei represent a key point in the understanding of delivered dose in cancer therapy application. The effect of fragmentation diminishes the number of primary ions delivered to the region under treatment and produce a tail of damaging ionisation beyond the Bragg peak. In addition the trajectories of fragments may be sufficiently perturbed compared to that of the incident ion that they deposit a non-negligible dose outside the volume of tissue being treated. Carbon ions are also a significant component of the Galactic Cosmic Radiation and therefore they contribute to the dose delivered to astronauts on long duration space missions. The external environment is fairly well known, but when the incident radiation interact with the spacecraft hull and internal materials, nuclear fragmentation modifies the external radiation field. By using an experimental setup based on thin and thick double sided microstrip silicon detectors has been possible to identify the fragmentation products due to the interaction of very high energy primary ions on different targets. The analysis of different charge distribution of different fragments is based on a Likelihood approach. Here we report total and partial cross-sections measured at GSI, Darmstadt, For 500 MeV/n energy 12 C beam incident on water (in flasks), polyethylene, lucite, silicon carbide, graphite, aluminium, copper, iron, tin, tantalum and lead targets. The results are compared to the predictions of GEANT4 and FLUKA Monte Carlo simulation programs .

Speaker: Dr Behcet Alpat (INFN Sezione di Perugia)

Slides Alpat_G4SUW2013_Final.pdf (Protected)

09:40 Energetic nucleus-nucleus interaction models for Geant4 – an update

Nucleus-nucleus interactions have been acknowledged as of growing importance for simulations of aerospace radiation effects: energetic nuclei and nuclear fragments can have disproportionate effects both on the high-LET dose received during human spaceflight, and the single event threat to microelectronics in space and for aircraft in the upper atmosphere. Indeed, at high altitudes in the atmosphere it is essential to accurately quantify the residual primary cosmic ray and secondary nuclear fragment environment as these particles may dominate SEE rates. Previous work on improving simulation of nucleus-nucleus collisions has led the DPMJET-II.5 interface to Geant4. This paper reviews the work undertaken to extend the DPMJET modelling capability to treat a wider range of particles.

Speaker: Dr Pete Truscott (Kallisto Consultancy Ltd)

10:00 Preliminary study about biological effects in DNA from proton irradiation using electrophoresis and Geant4-DNA

Objective In order to evaluate space mission hazards, we need to understand the effects of ionizing radiation in the human body on a microscopic scale. DNA damages impact directly on the fate of irradiated biological cells. Early DNA damages result from physical, physico-chemical and chemical interactions on cellular DNA. In this study, we present the experimental irradiation of plasmid DNA using protons. DNA damages have been quantified using electrophoresis. Simulation results using the Geant4-DNA extension of the general purpose Geant4 Monte Carlo toolkit are also presented. Methods The National Cancer Center (NCC) is equipped with a proton therapy cyclotron facility including the IBA Beam Nozzle. We used a proton beam Bragg peak of range 14 cm. The setup has been fully simulated with Geant4 and the validation of proton scattering is currently on going. Thanks to these simulations, it is now possible to simulate the characteristics of the beam at nozzle exit. Plasmid DNA samples were exposed to the proton beam at nozzle exit and DNA damages were measured indirectly using electrophoresis. Results We analysed dose distribution in matter using Geant4. Experimental data were compared with simulation results. In these results, we found the relationship between DNA damages and dose. Further validation is needed using more biological experiments

Speaker: Mr Jae-ik Shin (National Cancer Center at Korea)

Slides jishin_g4psace2013_2.pdf (Protected)

10:20 Charge transport in semiconductor crystals

We present an implementation of charge transport physics in cryogenically cold semiconductor crystals using the Geant4 toolkit. The code presented is capable of simulating the transport of electrons and holes within Germanium crystals, taking into account conduction band anisotropies and Luke-Neganov scattering. We discuss the detailed implementation of charge transport physics presented, along with our validation efforts and physics applications, such as line broadening in cryogenic calorimeters. Coherent crystal interactions such as channeling and extensions of the framework to room temperature will also be discussed.

Speaker: Dr Daniel Brandt (KIPAC, SLAC National Accelerator Lab, Stanford)

Slides Brandt_CMPCharge_G4SUW2013.pdf

10:40 → 11:00 Coffee break

11:00 → 12:40 Geant4 updates

11:00 General Status Report

Speaker: Dr Marc VERDERI (LLR / Ecole polytechnique)

Slides Verderi_Geant4StatusAndBiasing.pdf (Protected)

11:25 Recent upgrade and status of Geant4 electromagnetic physics

An overview will be presented on Geant4 electromagnetic (EM) physics for the recent Geant4 version 9.6. New physics models, EM physics constructors, and validation results will be discussed.

Speaker: Prof. Vladimir Ivantchenko (CERN, G4AI)

Slides Ivantchenko_Geant4EMPhysics96.pdf

11:50 Hadronic Physcis Updates

Speaker: Dr José Manuel Quesada (University of Sevilla)

Slides Quesada_G4Hadronic_updates.pdf

12:15 Geant4 Version 10

Speaker: Dr Makoto ASAI (SLAC)

Slides Asai_TowardGeant4Version10.pdf

12:40 → 13:10 Closing Remarks and Workshop Clausure

13:10 → 14:30 Lunch

15:30 → 18:00 Visit to BSC