Performance of an HRPPD in Tesla-scale magnetic fields

B. Azmoun; Y. Ilieva; Y. Jin; J. Kim; A. Kiselev; B. S. Page; M. Popecki; M. L. Purschke; A. Tamis; V. Teotia; C. P. Wong; C. Woody

arXiv · 2608.07858

Performance of an HRPPD in Tesla-scale magnetic fields

B. Azmoun·Y. Ilieva·Y. Jin·J. Kim·A. Kiselev·B. S. Page·M. Popecki·M. L. Purschke·A. Tamis·V. Teotia·C. P. Wong·C. Woody

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Abstract

High-Rate Picosecond Photodetectors (HRPPDs) are state-of-the-art microchannel-plate (MCP) photodetectors that offer excellent timing and spatial resolution, together with high single-photon detection efficiency. They are currently being considered for the ePIC experiment at the future Electron Ion Collider (EIC) at Brookhaven National Laboratory. A key requirement for the application of this technology is reliable operation in a strong magnetic field up to 1.5 T, with magnetic flux lines at an inclination of $\le15^\circ$ to the normal of the MCP surface. Magnetic field-induced distortions of the collected charge in MCP-based detectors can be compensated by tuning the operating parameters; however, the objective of this study is to quantify this performance in the case of the EIC-HRPPD, a particular MCP stack-up specialized for operation within ePIC. This photosensor employs a high quantum efficiency photocathode, 10$~\mu$m capillary pores, narrow transfer gaps, and a custom ceramic pixelated DC-coupled readout. This article explores the optimal operating parameters (mainly the voltages applied across the gaps and the MCPs) for single photon detection at various inclination angles in a uniform field up to 1.8 T. Ultimately, it was found that the gain and single photon detection efficiency of the HRRPD could be recovered over a range of polar inclination angles up to $\pm35^\circ$.

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B. Azmoun, Y. Ilieva, Y. Jin, J. Kim, A. Kiselev, B. S. Page, M. Popecki, M. L. Purschke, A. Tamis, V. Teotia, C. P. Wong, C. Woody. 2026-08-08. Performance of an HRPPD in Tesla-scale magnetic fields. https://arxiv.org/abs/2608.07858

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