Gaia: segmented germanium detector for high-energy X-ray fluorescence and spectroscopic imaging

Journal Article · Thu Jan 01 00:00:00 UTC 2026 · Journal of Synchrotron Radiation (Online)

DOI: https://doi.org/10.1107/s1600577525009294 · OSTI ID:3001647

Rumaiz, Abdul K.  ^[1]; Capocasa, Francesca  ^[2]; Kuczewski, Anthony J. ^[1]; Pinaroli, Giovanni  ^[2]; Li, Ji  ^[1]; Kuczewski, John ^[2]; Finnelli, Kristina ^[2]; Koh, Katherine  ^[3]; Shutlz-Johnson, Lorianne ^[3]; Fitzgerald, Carter  ^[3]; Krings, Thomas  ^[4]; Vo, Nghia T.  ^[1]; Drakopoulos, Michael  ^[1]; Zhong, Zhong  ^[1]; Caswell, Thomas ^[1]; Siddons, D. Peter  ^[1]

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1. Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)
2. Brookhaven National Laboratory (BNL), Upton, NY (United States)
3. Savannah River National Laboratory (SRNL), Aiken, SC (United States)
4. Forschungszentrum Juelich (Germany)

We present Gaia, a monolithic array of 96 high-purity germanium pixel detectors integrated with a custom low-noise application-specific integrated circuit (ASIC) and a field-programmable gate array (FPGA)-based data acquisition system. The sensor operates at ∼100 K using a commercial closed-cycle cryocooler, with the in-vacuum electronics thermally isolated from the cold finger to ensure thermal stability. The system demonstrates an average energy resolution of 711 eV at 122 keV, measured using a ⁵⁷Co source, and 253 eV at 5.89 keV, measured with ⁵⁵Fe across all channels. The readout architecture incorporates a high-performance FPGA paired with a dual-core ARM processor, forming a complete embedded Linux-based computing platform. Communication between the processor and FPGA is handled via memory-mapped I/O, and data are streamed over high-speed gigabit Ethernet. A full-scale 384-pixel Gaia detector, based on this 96-element module, is currently under fabrication.

• Research Organization: Brookhaven National Lab
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation; USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)
• Grant/Contract Number: SC0012704
• OSTI ID: 3001647
• Report Number(s): BNL--229135-2025-JAAM
• Journal Information: Journal of Synchrotron Radiation (Online), Journal Name: Journal of Synchrotron Radiation (Online); ISSN 1600-5775
• Publisher: International Union of CrystallographyCopyright Statement
• Country of Publication: United States
• Language: English