Short Courses

ANIMMA 2011 Short Courses (June 6, 2011, ICC Ghent)

 Nuclear radiation detection: Principles and applications from today to tomorrow

  Abdallah Lyoussi (CEA/DEN/DER and CEA/INSTN) and

Daniel Beretz (CEA/DEN/DER/SPEx)

 Radiation detection and measurement methods

Starting from the physical principles, the course will discuss the performances and the limitations of various radiation detectors that can be used in nuclear reactors and in the subsequent stages of the nuclear fuel cycle. Two specific applications will illustrate the practical applications of the detection techniques: neutron dosimetry in fission reactors and nuclear monitoring of the fuel cycle (passive and active neutron measurements, sensing via photofission, coupling of measurements and combined interpretation).

The course will be structured as follows:

1.      Interaction of radiation with matter

2.      Physical principles of main radiation detectors

a.      Gas-filled detectors

b.      Scintillation detectors

c.      Solid-state detectors (semiconductor, diamond, TLD)

d.      Activation detectors

3.      Examples of specific measurement methods and their applications

a.      Neutron dosimetry in fission reactors

b.      Nuclear non-destructive assay in nuclear fuel cycle

 Luc Van Hoorebeke (Ghent Univ.)

Revealing the secrets in a gamma ray spectrum

The differential pulse height spectrum which is measured when a monoenergetic gamma-ray source is placed in the vicinity of a gamma-ray detector is called the response function of the detector for the energy of the photons emitted by the source. This pulse height spectrum exhibits typically much more features than simply a single peak with a certain energy resolution at the emitted photon energy. This is due to the various possible interaction mechanisms of gamma-ray photons in matter. In the context of gamma-ray spectroscopy, the significant photon interaction processes in the detector are photoelectric absorption, Compton scattering and pair production. These processes are at the origin of distinct features in the response function such as the photopeak, the Compton edge and the Compton continuum, and the single and double escape peaks. Moreover, processes taking place in the gamma-ray source encapsulation and the detector surrounding materials can yield additional contributions to the observed spectrum such as the annihilation peak, the backscatter peak, a bremsstrahlung contribution and characteristic X-ray peaks.

In this short course, it will be explained how all processes contribute to the actual observed detector response function, yielding its distinct features which are dependent on incident photon energy, detector characteristics and other variables.

George Imel (Idaho State Univ., Univ. de Provence)

 Towards future nuclear systems: fast neutron detection

The current developments in the frameworks of fusion and Gen-IV fission reactors require improved techniques for the monitoring of fast neutrons. This short course will provide a general overview of the methods of fast neutron detection.

We will start with a quick discussion of what constitutes a “fast” neutron and how the reaction mechanisms are different from thermal or epithermal neutron, followed by a brief discussion of the applications of fast neutron detectors (spectroscopy, lead slowing-down assay methods, etc.).

The majority of the course will cover the methods of fast neutron detection starting with passive. A presentation of useful foil detectors and spectral unfolding methods from measured reaction rates will be made. Then, active methods will be discussed, including threshold fission chambers and recoil devices.

A discussion of the typical uncertainties (which are generally quite higher than thermal or epi-thermal measurements) will conclude the course.

The scheme of the course:

    1. Introduction

a.       Fast neutron reactions of interest

b.       Uses of fast neutron detectors

     2. Methods

a.       Passive

1.       Foils of interest

2.       Unfolding theory

3.       Examples

b.       Active

1.       Threshold fission chambers

2.       Recoil methods (e.g., proton recoil)

3.       Indirect recoil methods (He-3, Li-6)

4.       Slowing-down (lead, bonner spheres)

     3. General discussion of uncertainties

Jean-Marc Layet (Univ. de Provence)

 Advanced diagnostics concepts for fusion reactors

Development of diagnostics is crucial in fusion devices. They provide the measurements required for machine protection, plasma control and physics studies.

Due to the particular characteristics of fusion plasmas (hot plasma, plasma-wall interactions,..), diagnostics are based on a large variety of physical processes. The complexity of fusion reactors has motivated the development of various kinds of plasma diagnostics using the most advanced technologies. The aim of this conference is to give an introduction into the field of plasma diagnostics (including plasma-wall interaction) taken into account the harsh environment and unexplored ‘‘burning plasma’’ conditions of the next generation of fusion reactors (ITER); we will show that the development and integration of plasma diagnostics in ITER is a major challenge.

SCHEDULE

The courses will be given at the ANIMMA Conference location (ICC Ghent, Belgium) on June 6, 2011, the day of the ANIMMA opening session (which will start at 17:00 hrs).

08:30 – 10:30    A. Lyoussi (parts 1-2)

10:30 – 10:45    Coffee Break

10:45 – 11:45    L. Van Hoorebeke

11:45 – 12:15    D. Beretz (part 3a)

12:15 – 12:45    A. Lyoussi (part 3b)

12:45 – 13:30    Lunch

13:30 – 15:00    G. Imel

15:00 – 15:15    Coffee Break

15:15 – 16:45    J.-M. Layet

ECTS

For PhD students, the possibility will be offered to acquire ECTS points for the ANIMMA short courses as a whole. For that purpose we will organize an optional exam consisting of multiple-choice questions covering all courses.

FEE

This fee includes attendance to all courses, one copy of the course notes, a certificate of attendance (and an ECTS certificate if successfully passed the optional exam), one lunch and two coffee breaks.