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arXiv · 2312.07503

Scintillation of Ar/CF$_4$ mixtures: glass-THGEM characterization with 1% CF$_4$ at 1-1.5 bar

P. Amedo·R. Hafeji·A. Roberts·A. Lowe·S. Ravinthiran·S. Leardini·K. Majumdar·K. Mavrokoridis·D. González-Díaz
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Abstract

Argon gas doped with 1% wavelength-shifter (CF$_4$) has been employed in an optical time projection chamber (OTPC) to image cosmic radiation. We present results obtained during the system commissioning, performed with two stacked glass-THGEMs and an EMCCD camera at 1 bar. Preliminary estimates indicate that the combined optical gain was of the order of 10$^6$ (ph/e), producing sharp and high-contrast raw images without resorting to any filtering or post-processing. A first assessment of the impact of pressurization showed no change in the attainable gains when operating at 1.5 bar

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P. Amedo, R. Hafeji, A. Roberts, A. Lowe, S. Ravinthiran, S. Leardini, K. Majumdar, K. Mavrokoridis, D. González-Díaz. 2023-12-12. Scintillation of Ar/CF$_4$ mixtures: glass-THGEM characterization with 1% CF$_4$ at 1-1.5 bar. https://arxiv.org/abs/2312.07503

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