Speaker
Mr
Dariusz MAKOWSKI
(Department of Microelectronics and Computer Science, Technical University)
Description
Radiation present in an accelerator poses a real threat to electronic
devices and systems placed in the main tunnel. Radiation in the
accelerator tunnel is produced as a result of the electron beam's
interaction with high-Z materials. Because of the Total Ionizing Dose
effect gamma radiation is responsible for a long term degradation of all
devices installed in the accelerator's chamber. Neutrons are responsible
for Single Event Effects that generate malfunctions in digital systems
and they could result in repairable or hard damage of the devices.
Therefore gamma radiation and neutrons monitoring is strictly
recommended to avoid the unwanted breakdown of the control system. The
paper presents the system dedicated for gamma radiation and neutrons
monitoring in a linear accelerator in real-time. The presented detector
is intended to be used in the newly installed X-Ray Free-Electron Laser
X-FEL at DESY research centre in Hamburg. Two different detectors were
used to monitor gamma radiation and neutrons. The radiation sensitive
transistor RADFET is responsible for gamma radiation measurement whereas
SRAM-based detector was used to measure neutron fluence in the tunnel.
The radiation-selective sensors are connected to the
microcontroller-based read-out system. The system was built with the
usage of redundant elements to assure radiation tolerance. Measured data
are gathered in a database, thus gamma radiation and neutron fluence
history is accessible. These parameters help to predict damage of
electronic systems that are placed in the tunnel. We have conducted a
few experiments with the system at DESY. The devices were exposed to a
neutron field from an Americium-Beryllium neutron source 241AmBe. The
systems were installed in two accelerators: VUV-FEL as a prototype of
X-FEL accelerator and Linac II. The results of the operation within a
few months are discussed in the paper.
Author
Mr
Dariusz MAKOWSKI
(Department of Microelectronics and Computer Science, Technical University)
Co-authors
A. NAPIERALSKI
(TECHNICAL UNIVERSITY OF LODZ, POLAND)
B. MUKHERJEE
(DESY)
M. GRECKI
(TECHNICAL UNIVERSITY OF LODZ, POLAND)
Dr
Stefan SIMROCK
(DESY)
