Receivers for the Black Hole Explorer (BHEX) Mission

C. Edward Tong; Kazunori Akiyama; Paul Grimes; Mareki Honma; Janice Houston; Michael D. Johnson; Daniel P. Marrone; Hannah Rana; Yoshinori Uzawa

doi:10.1117/12.3018054

arXiv · 2406.09558

Receivers for the Black Hole Explorer (BHEX) Mission

C. Edward Tong·Kazunori Akiyama·Paul Grimes·Mareki Honma·Janice Houston·Michael D. Johnson·Daniel P. Marrone·Hannah Rana·Yoshinori Uzawa

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Abstract

In this paper, we introduce the receiver architecture for the Black Hole Explorer (BHEX) Mission, designed to reveal the photon ring of black holes. The primary instrument is a dual-polarization receiver operating over the 240-320 GHz frequency range, utilizing a Superconductor-Insulator-Superconductor (SIS) mixer. This Double-Side-Band (DSB) receiver has an intermediate frequency (IF) range of 4-12 GHz and operates at a bath temperature of 4.5 K, for optimal performance, which necessitates the integration of a cryocooler. Complementing the primary receiver is a secondary unit covering the 80-106 GHz spectrum, featuring a cryogenic low noise amplifier. This secondary receiver, affixed to the 20 K stage of the cryocooler, serves to augment the SIS receiver performance by employing the Frequency Phase Transfer technique to boost the signal-to-noise ratio at the correlator output. Together, this sophisticated receiver duo is engineered to achieve the quantum-limited sensitivity required to detect the photon ring of black holes, marking a breakthrough in astrophysical observation.

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C. Edward Tong, Kazunori Akiyama, Paul Grimes, Mareki Honma, Janice Houston, Michael D. Johnson, Daniel P. Marrone, Hannah Rana, Yoshinori Uzawa. 2024-06-13. Receivers for the Black Hole Explorer (BHEX) Mission. https://doi.org/10.1117/12.3018054

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