A high-precision, low-noise camera for transiting photometry based on CMOS sensor stitching with high stability of gain

The research team carried out the development and performance evaluation of a low-noise, high gain-stability camera for transiting photometry. With China's independently developed CMOS sensors as its cores and in response to the needs of high-precision photometry, the camera adopts a multi-sensor stitching scheme with techniques such as low-noise power supplies, vacuum cooling, precise assembly and alignment. Particularly, it has achieved a high stability of gain by optimizing the gain bias circuit and applying a high-precision temperature control for the sensors. With a high-precision photometric platform, the research team conducted long-term observations of a 12.5-magnitude star with the camera. The results show that both the readout noise and dark current are controlled at expected low levels. The camera’s photometric precision enables effective detection of the varied weak light signals caused by transiting of Earth-sized planets.