flashDiamond Detector

The New Single Crystal Diamond Detector for FLASH Dosimetry

The Detector for FLASH Dosimetry Needs

Real-time dosimetry of ultra-high dose rate (UHDR) as currently used for the investigation of the so-called FLASH effect is particularly challenging. Until now, commercially available detectors typically used in conventional radiotherapy have not been suitable for FLASH dosimetry due to recombination, saturation, or nonlinearity effects.

The new PTW flashDiamond detector, which was developed in cooperation with the University of Rome “Tor Vergata”, has been successfully tested for relative dosimetry in UHDR conditions, but is also a promising candidate for reference dosimetry.

PTW flashDiamond at Heidelberg University Hospital — Photo: Courtesy of University Hospital Heidelberg

flashDiamond* for Relative and Reference Dosimetry

The flashDiamond uses the same technology as the well-established microDiamond detector, but has been optimized to meet the specific demands of FLASH radiation. Its superior performance characteristics, proven through extensive testing at various UHDR linacs, make it an ideal detector for a wide range of UHDR applications.

The detector has been successfully used for relative 3D dose distribution measurements in UHDR beams without the need for correction factors and is also potentially suitable for use in reference dosimetry. Combined with the optional flashAdapter, the flashDiamond is compatible with PTW electrometers and water phantoms for precise dose measurements.

Highlights

Excellent radiation hardness
High spatial and temporal resolution
Nearly water equivalent for all beam energies
Minimal energy, temperature and directional dependence

Very good linearity up to 8 Gy/pulse at a pulse length of 4 μs
Suitable for field sizes of 1 cm x 1 cm ... 20 cm x 20 cm
Nominal active diameter 1.2 mm
Axial or radial direction of incidence

*for research use only

Publication Highlight:

“Metrology for advanced radiotherapy using particle beams with ultra-high dose rates”

Interested in an update in FLASH dosimetry? Read the comprehensive report by Anna Subiel et al 2024 Phys. Med. Biol. 69 14TR01 which summarizes the results of the European UHDpulse project and other initiatives aiming to support the safe translation of FLASH-RT into clinical practice. The article reviews recent developments in FLASH dosimetry, focusing on primary and secondary standard instruments, which also include PTW detector developments.

Download topical review (open access)

Publication Highlight: “Metrology for advanced radiotherapy using particle beams with ultra-high dose rates”

Selected Publications

Characterization of the PTB ultra-high pulse dose rate reference electron beam A Bourgouin, A Knyziak, M Marinelli, R Kranzer, A Schüller, RP Kapsch Physics in Medicine & Biology 67 (8), 085013

Application of a novel diamond detector for commissioning of FLASH radiotherapy electron beams G Verona Rinati, G Felici, F Galante, A Gasparini, R Kranzer, G Mariani, ... Medical Physics 49 (8), 5513-5522

Diamond detectors for dose and instantaneous dose‐rate measurements for ultra‐high dose‐rate scanned helium ion beams T Tessonnier, G Verona‐Rinati, L Rank, R Kranzer, A Mairani, M Marinelli Medical Physics 51 (2), 1450-1459

Design, realization, and characterization of a novel diamond detector prototype for FLASH radiotherapy dosimetry M Marinelli, G Felici, F Galante, A Gasparini, L Giuliano, S Heinrich, ... Medical Physics 49 (3), 1902-1910

Metrology for advanced radiotherapy using particle beams with ultra-high dose rates A Subiel, A Bourgouin, R Kranzer, P Peier, F Frei, F Gomez, A Knyziak, ... Physics in Medicine and Biology

Response of diamond detectors in ultra-high dose-per-pulse electron beams for dosimetry at FLASH radiotherapy R Kranzer, A Schüller, A Bourgouin, T Hackel, D Poppinga, M Lapp, ... Physics in Medicine & Biology 67 (7), 075002

A diamond detector based dosimetric system for instantaneous dose rate measurements in FLASH electron beams M Marinelli, F di Martino, D Del Sarto, JH Pensavalle, G Felici, L Giunti, ... Physics in Medicine & Biology 68 (17), 175011

OC-0283 Diamond detectors as a powerful real-time tool for commissioning UHDR electron beams in water A Gasparini, G Felici, F Galante, F Gomez, R Kranzer, G Mariani, ... Radiotherapy and Oncology 170, S243-S244

PP13.08 Characterization of flashDiamond Detectors for Reference Dosimetry at FLASH Radiotherapy with Electrons A. Schüller, C. Weber, R. P. Kapsch, R. Kranzer Abstracts / Physica Medica 125S1 (2024) S1–S510, S307-308