Proton Radiation Damage and Annealing of COSI p-type Cross-strip HPGe Detectors

Sophia E. Haight; Steven E. Boggs; Gabriel Brewster; Sean N. Pike; Jarred M. Roberts; Albert Y. Shih; Joanna M. Szornel; John A. Tomsick; Aravind B. Valluvan; Andreas Zoglauer

arXiv · 2501.02412

Proton Radiation Damage and Annealing of COSI p-type Cross-strip HPGe Detectors

Sophia E. Haight·Steven E. Boggs·Gabriel Brewster·Sean N. Pike·Jarred M. Roberts·Albert Y. Shih·Joanna M. Szornel·John A. Tomsick·Aravind B. Valluvan·Andreas Zoglauer

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Abstract

In order to understand the effects of a space radiation environment on cross-strip germanium detectors, we investigated the effects of high-energy proton damage on a COSI detector and the capabilities of high-temperature annealing in repairing detector spectral resolution. We irradiated a COSI-balloon cross-strip high-purity germanium (HPGe) detector with 150 MeV protons resulting in a net fluence of $4.95\times10^8$ p$^+$/cm$^2$ and corresponding to ~10 years in COSI's space radiation environment. We repaired the resulting degradation in spectral resolution through a series of high-temperature anneals to obtain a final FWHM of 4.08 keV, within 37% of its preradiation value (2.98 keV FWHM). We characterized the repair of charge traps with time spent under high-temperature anneal to inform an annealing procedure for long-term maintenance of COSI's spectral resolution.

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Sophia E. Haight, Steven E. Boggs, Gabriel Brewster, Sean N. Pike, Jarred M. Roberts, Albert Y. Shih, Joanna M. Szornel, John A. Tomsick, Aravind B. Valluvan, Andreas Zoglauer. 2025-01-05. Proton Radiation Damage and Annealing of COSI p-type Cross-strip HPGe Detectors. https://arxiv.org/abs/2501.02412

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