Development of a Compton imager setup
Name
12036_2025_10110_ReferencePDF.pdf
Size
5.31 MB
Format
Adobe PDF
Checksum (MD5)
3854877520fc6122fef597918ca748cc
Author(s)
Arya, Anuraag
Bilkhu, Harmanjeet S.
Vishwakarma, Sandeep
Belatikar, Hrishikesh
Bhalerao, Varun
Ghodgaonkar, Abhijeet
Koyande, Jayprakash G.
Marathe, Aditi
Mithun, N. P. S.
Narang, Sanjoli
Date Issued
November 4, 2025
Journal
Journal of Astrophysics and Astronomy
Publisher
Springer India
Citation
Arya, A., Bilkhu, H.S., Vishwakarma, S. et al. Development of a Compton imager setup. J Astrophys Astron 46, 84 (2025).
Version
Author's final manuscript
Abstract
Hard X-ray photons with energies in the range of hundreds of keV typically undergo Compton scattering when they are incident on a detector. In this process, an incident photon deposits a fraction of its energy at the point of incidence and continues onwards with a change in direction that depends on the amount of energy deposited. By using a pair of detectors to detect the point of incidence and the direction of the scattered photon, we can calculate the scattering direction and angle. The position of a source in the sky can be reconstructed using many Compton photon pairs from a source. We demonstrate this principle in the laboratory by using a pair of Cadmium Zinc Telluride (CZT) detectors sensitive in the energy range of 20–200 keV, similar to those used in AstroSat/CZT Imager (CZTI). The laboratory setup consists of two detectors placed perpendicular to each other in a lead-lined box. The detectors are read out by a custom-programmed Xilinx PYNQ-Z2 FPGA board, and data are then transferred to a personal computer (PC). There are two key updates from CZTI: the detectors are read concurrently rather than serially, and the time resolution has been improved from 20 to 7.5 μ s. We irradiated the detectors with a collimated 133 Ba source and identified Compton scattering events for the 356 keV line. We run a Compton reconstruction algorithm to correctly infer the location of the source in the detector frame, with a location-dependent angular response measure of 16 ∘ –30 ∘ . This comprises a successful technology demonstration for a Compton imaging camera in the hard X-ray regime. We present the details of our setup, the data acquisition process, and software algorithms, and showcase our results. We also quantify the limitations of this setup and discuss ways of improving the performance in future experiments.
MIT Department
Massachusetts Institute of Technology. Computer Science and Artificial Intelligence Laboratory
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1007/s12036-025-10110-7
