Metu-Defocusing Beamline - A 15-30 Mev Proton Irradiation Facility and Beam Measurement System
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2020-01-01 |
| Journal | EPJ Web of Conferences |
| Authors | B. Demirköz, Caner Seckin, Akanay AvaroÄlu, Besna Bulbul, Pelin Uslu |
| Institutions | Middle East Technical University, Karadeniz Technical University |
| Citations | 8 |
| Analysis | Full AI Review Included |
Executive Summary
Section titled âExecutive SummaryâThe METU-DBL (Defocusing Beam Line) project establishes a high-energy proton irradiation facility dedicated to radiation hardness testing, adhering strictly to engineering specifications.
- Core Capability: Provides 15 MeV to 30 MeV kinetic energy protons for testing materials, detectors, and electronics in high-radiation environments.
- Standard Compliance: The facility is designed to meet the stringent requirements of the ESA/ESCC No: 25100 standard for Single Event Effect (SEE) tests.
- Performance Metrics: Offers a wide, selectable flux menu ranging from 105 p/cm2/s up to 1011 p/cm2/s, allowing high-fluence tests (1014 p/cm2) in approximately 20 minutes.
- Beam Control: Utilizes a 5-port switching magnet, custom-designed quadrupole magnets (up to 7.5 T/m gradient), and an adjustable conical collimator for precise flux and beam size control.
- Uniformity and Area: Achieves a large, uniform irradiation area (15.40 x 21.55 cm2) with ±10% uniformity, facilitated by titanium scattering foils cooled by a dedicated helium chamber.
- Monitoring System: Beam flux and profile are continuously monitored using a sophisticated measurement system incorporating Timepix3 pixel detectors, fiber scintillators, and radiation-enduring diamond detectors.
- Target Applications: Supports R&D for Hi-Lumi LHC upgrades, space electronic components, and nuclear material research.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Proton Energy Range (Operational) | 15 - 30 | MeV | Cyclotron output range |
| Proton Energy Range (Standard) | 20 - 200 | MeV | ESA/ESCC No: 25100 requirement |
| Selectable Flux Range | 105 - 1011 | p/cm2/s | METU-DBL operational range |
| Minimum Standard Flux | 108 | p/cm2/s | ESA/ESCC No: 25100 minimum |
| Standard Beam Area | 15.40 x 21.55 | cm2 | Required area for SEE tests |
| Beam Uniformity | ± 10 | % | Required uniformity across test area |
| Required Vacuum Level | 10-6 | mbar | Pressure inside the beam pipe |
| Total Cooling Capacity | 50 | kW | Capacity of the cooling subsystem |
| Custom Quadrupole Gradient | 7.5 | T/m | Maximum gradient strength |
| Custom Quadrupole Current | 160 | A | Nominal operating current |
| Scattering Foil Thickness | 50 | ”m | Thickness of Titanium foils |
| Helium Chamber Dimensions | 150 x 100 x 140 | mm3 | Volume for cooling scattering foils |
| Conical Collimator Aperture Range | 1 x 1 to 10 x 10 | mm2 | Adjustable range for flux control |
| Test Table Scan Range (X-axis) | ± 760 | mm | Final design robotic system limit |
| Test Table Scan Range (Y-axis) | + 670 | mm | Final design robotic system limit |
Key Methodologies
Section titled âKey MethodologiesâThe METU-DBL facility employs a multi-stage process for beam preparation, delivery, and monitoring to ensure compliance with radiation testing standards:
- Beam Injection and Switching: Protons (15-30 MeV) are sourced from the cyclotron and directed into the METU-DBL beamline via a 3-ton, 5-port switching magnet, located at the right-most port.
- Beam Optics and Enlargement: The proton beam is enlarged using a system of three quadrupole magnets (two commercial, one custom-designed) to achieve the required large area and uniformity (7.5 T/m gradient).
- Flux Attenuation: An adjustable conical collimator is used to precisely reduce the proton flux, offering users a wide range of fluence options (105 to 1011 p/cm2/s).
- Uniformity Enhancement and Cooling: The beam passes through two 50 ”m titanium scattering foils to induce multiple Coulomb scattering, homogenizing the field. These foils are actively cooled using a dedicated helium gas chamber (150 x 100 x 140 mm3) to manage the 3 kW thermal load generated by the 30 MeV, 100 ”A beam.
- Beam Profile Monitoring: A movable beam screen (Al2O3 plate at 45°) is inserted into the beam path to observe the beam profile and align the mechanical installation, analyzed using ImageJ software.
- Flux and Dose Measurement: Proton flux and uniformity are measured at the target area using three complementary detectors:
- Timepix3 Pixel Detector: Provides high-resolution spatial information (55 ”m pixel size).
- Fiber Scintillators: Used to infer proton flux by measuring generated photon flux.
- Diamond Detectors: Used for spot checks and calibration due to their high radiation endurance.
- Robotic Sample Management: Devices Under Test (DUTs) are placed on a large robotic test table (760 mm x 670 mm scan area) controlled by servo motors, allowing autonomous or manual positioning for sequential irradiation.
- Shielding and Safety Analysis: FLUKA simulation program is utilized for calculating particle transport, activation, and dosimetry. Shielding designs incorporate aluminum, polyethylene, and lead to protect sensitive electronics and personnel.
Commercial Applications
Section titled âCommercial ApplicationsâThe METU-DBL facility is critical infrastructure for industries requiring certification and validation of components operating in extreme radiation environments.
- Aerospace and Defense:
- Testing space-grade electronics for Single Event Effects (SEEs) caused by trapped protons and solar flares, ensuring satellite and deep-space probe reliability.
- Radiation Hardness Assurance (RHA) testing for avionics and military systems.
- High Energy Physics (HEP):
- Irradiation testing of detectors, sensors, and materials intended for accelerator upgrades, specifically the high-dose environment of the Hi-Lumi LHC.
- Nuclear Energy and Research:
- Material science research focused on radiation damage and tolerance for components used in nuclear facilities and fusion reactors.
- Semiconductor Manufacturing:
- Qualification and certification of commercial-off-the-shelf (COTS) and custom semiconductor devices for use in radiation-exposed systems, adhering to standards like ESA/ESCC.
- Medical Technology:
- Future testing of materials and electronics used in medical imaging equipment or radiation therapy delivery systems.
View Original Abstract
Middle East Technical University - Defocusing Beam Line (METU-DBL) project is an irradiation facility providing 15 MeV to 30 MeV kinetic energy protons for testing various high radiation level applications, ranging from Hi-Lumi LHC upgrade, space electronic components to nuclear material research. The project located inside the premises of the TAEA (Turkish Atomic Energy Agency) SANAEM (Saraykoy Nuclear Education and Research Center) close to Ankara, provides users a wide selectable flux menu (10 5 -10 10 p/cm 2 /s). The facility is now being commissioned and the facility will be providing a large test area (20 cm x 15 cm) for material, detector and electronics tests. The proton beam is monitored along the beamline using aluminum oxide screens and the flux and uniformity is measured using three detectors attached to the robotic system for cross- checks. A fiber scintillator detector scans the large irradiation area while small area diamond detector and Timepix3 detector are used for spot checks for calibration. Several samples can be radiated simultaneously inside the irradiation area and the robotic system provides 5 separate holders for samples which can be moved in or out, providing users flexibility for the desired fluence. This talk will first introduce METU- DBL as a radiation test facility, then discuss the radiation monitoring of the beam area and the radiation room, while highlighting how this facility can be used for future testing of materials for radiation tolerance.