1. Development of a Compton Imager Setup
- Author
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Arya, Anuraag, Bilkhu, Harmanjeet Singh, Vishwakarma, Sandeep, Belatikar, Hrishikesh, Bhalerao, Varun, Ghodgaonkar, Abhijeet, Koyande, Jayprakash G., Marathe, Aditi, Mithun, N. P. S., Narang, Sanjoli, Nimbalkar, Sudhanshu, Page, Pranav, Palit, Sourav, Patel, Arpit, Shetye, Amit, Tallur, Siddharth, Tendulkar, Shriharsh, Vadawale, Santosh, and Waratkar, Gaurav
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics - 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 onward 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 detectors sensitive in the energy range of 20-200 keV. The laboratory setup consists of the two detectors placed perpendicular to each other in a lead-lined box. The detectors are read out by a custom-programmed Xilinx PYNQ FPGA board, and data is then transferred to a PC. The detectors are first calibrated using lines from $^{241}\mathrm{Am}$, $^{155}\mathrm{Eu}$ and $^{133}\mathrm{Ba}$ sources. We irradiated the detectors with a collimated $^{133}\mathrm{Ba}$ source and identified Compton scattering events for the 356 keV line. We run a Compton reconstruction algorithm and correctly infer the location of the source in the detector frame. 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., Comment: 17 pages, 10 figures, submitted for publication in Journal of Astronomical Telescopes, Instruments, and Systems (JATIS)
- Published
- 2024