1. Introduction ARDENT ESR5 Host Institute: Seibersdorf Laboratories Supervisor: DI Dr. Peter Beck
Jayasimha Vijaykumar BAGALKOTE, B.E, M.S
Seibersdorf Laboratories, Austria
ARDENT Workshop
Milano, 14 – 18, October 2013

2. Education - Undergraduate
1981 – 1999
Grew up in Bangalore (India)
1999– 2003
Electronics and Communications Engineering
University: Maulana Azad National Institute of Technology - Bhopal (India)
Final Degree: Bachelor

3. Education – Postgraduate
2005 – 2006
Information Technology
University: Scuola Superiore Sant´Anna, Pisa (Italy)
Final Degree: Master
2006
Research internship – Cognitive Neurosciences
Institute: International School for Advanced Studies Trieste (SISSA) - Trieste (Italy)
2006 – 2007
Courses in Cryptography, Rings and modules at University of Padova (Italy)
2008 – 2009
Courses in Sustainable Energy at University of Porto (Portugal)

4. Employment
2004 – 2005
Engineer (Design and Development) at Tata Elxsi Ltd, Bangalore
Software Testing and Development: Embedded Electronic devices
2009 – 2011
Research Engineer at Missler Software, Evry (France)
Computer Aided Manufacturing Software
Algorithms for Pencil machining operation
2011– 2012
IT Engineer at World Organisation for Animal Health, Paris
Database Testing
Automatizing Database-queries

5. My Interests in ARDENT
Gain expertise in radiation effects due to space radiation e.g. DNA-damage, microdosimetry, single event effects in electronics
Dosimetry in mixed radiation fields
PhD degree to increase my chances of obtaining a researcher position with teaching responsibilities

6. Proposed PhD Working Title Objectives Methods
Investigations on Space Radiation and its Effects to Humans and Electronic Components using Methods of Microdosimetry
Objectives
Compare measurements and numerical calculation of microdosimetry quantities in mixed radiation fields using TEPC
Undertake exposure experiments on electronic components in space radiation-like accelerator facilities using different shielding materials
Methods
Exposure experiments at accelerator facilities
Numerical simulations using Monte Carlo methods (FLUKA, GEANT4)

7. Space Radiation Environment
Investigate space radiation environment
Discuss effects of energy and particles:
Electrons
Protons
Neutrons
Heavy ions

8. Microdosimetry – TEPC EuCPAD: European Crew Personal Active Dosimeters
Team: DLR, SL, PTB, Tyndall, MIRION
Associated Partners: LNL-INFN, Univ. of Padova.
Radiation quality and dose in complex radiation field in Space at the International Space Station (ISS)
Document Astronaut’s exposures and support risk assessment
Activities:
Measurements of TEPC in irradiation facilities
Numerical simulation by Monte Carlo methods
For human space exploration accurate radiation risk assessment is of great importance. Due to the complexity of the radiation field in space as at the International Space Station (ISS) the development of appropriate radiation detectors to assess the radiation dose and quality remains a challenging task. ICRP proposes the use of linear energy transfer (LET), while ICRU suggests implementing the use of the lineal energy, y. Tissue equivalent proportional counter (TEPC) is the detector of choice to measure the event spectrum of lineal energy, y. ESA (HSO-UM, TEC) initiated the project called EuCPAD (European Crew Personal Active Dosemeters) to document the astronaut’s exposures, to support risk assessment and to provide a complete data set for space crew dose management offering systems capabilities for medical monitoring at highest medical and technical standards. A new spherical TEPC is expressively developed to provide the reference dosimetry at the ISS. The project is contracted under ESA Contract Nr /09/NL/CP (PM: M. Dieckmann) to a consortium led by DLR in collaboration with SL (AIT earlier than 2013), PTB, MIRION and Tyndall. The TEPC development is coordinated by SL in collaboration with LNL-INFN and the University of Padova. The electronics is developed by DLR. The measurement range of the imparted energy has to be between 0.2 keV and 2 MeV. Here we describe the detector system and present recent measurements carried out in various irradiation facilities.

9. Space radiation effects in electronics
Total Ionizing Dose Effects (TID)
Charge Accumulation Effects
Displacement effects
Single Event Effects (SEE)
Single densely ionizing particle effect
Critical charge density along the track
e.g. single event burnout, single event gate rupture, single event latch-up, single event upset
Cumulated Ionization in oxides:
Also called TID: Total Ionizing Dose
a/ Mechanism:
• electron-hole pair creation (absorption of a γ photon, …);
• partial recombination (strong if no electric field);
• electrons: high mobility => leave the oxide;
• holes: very low mobility => mostly trapped
b/ Result:
• net positive charge trapped in the oxide
(long term trapping at room temperature)
Instantaneous ionization in oxides:
Also called SEE: Single Event Effect
• A single highly ionizing particle (incident or secondary ion) cross the oxide
• High electron-hole pair density along the track;
• The track becomes temporarily conductive;
• Bias across the oxide => transient current appears across the oxide along
the ionized track;
This mechanism can be helped by the electrical field induced in SiO2 by
charges created in Si by the single ionizing particle.

10. Shielding Study
e2-RAD: Energetic Electrons Radiation Assessment Study for JUICE (JUpiter ICy moons Explorer) Mission
Investigate shielding (materials, geometry, layers, thicknesses)
Experiments for measurements in electron radiation field: MeV
Study degradation due to exposure in RadFET
Numerical modelling using GEANT4 and FLUKA.
e- particle source
For human space exploration accurate radiation risk assessment is of great importance. Due to the complexity of the radiation field in space as at the International Space Station (ISS) the development of appropriate radiation detectors to assess the radiation dose and quality remains a challenging task. ICRP proposes the use of linear energy transfer (LET), while ICRU suggests implementing the use of the lineal energy, y. Tissue equivalent proportional counter (TEPC) is the detector of choice to measure the event spectrum of lineal energy, y. ESA (HSO-UM, TEC) initiated the project called EuCPAD (European Crew Personal Active Dosemeters) to document the astronaut’s exposures, to support risk assessment and to provide a complete data set for space crew dose management offering systems capabilities for medical monitoring at highest medical and technical standards. A new spherical TEPC is expressively developed to provide the reference dosimetry at the ISS. The project is contracted under ESA Contract Nr /09/NL/CP (PM: M. Dieckmann) to a consortium led by DLR in collaboration with SL (AIT earlier than 2013), PTB, MIRION and Tyndall. The TEPC development is coordinated by SL in collaboration with LNL-INFN and the University of Padova. The electronics is developed by DLR. The measurement range of the imparted energy has to be between 0.2 keV and 2 MeV. Here we describe the detector system and present recent measurements carried out in various irradiation facilities.

11. Current activities Literature review
Enrollment into PhD programme at Technical University of Graz
Enrollment into German language course
Visit of ESA/ESTEC to discuss about training/secondment.
Training course on FLUKA (7-11 October, 2013)

12. Future Steps Training course on GEANT4 2013/2014.
Discuss and finalize upon options for secondment.
Visit of CERN radiation effects to components
TEPC experiments at HIMAC, Japan
Exposure of EEE components at PSI

13. Thank you for your attention!13