The MPIA detector system for the LBT instruments LUCIFER and LING-NIRVANA

摘要

We describe the detector subsystem developed at MPIA to operate the Rockwell Hawaii-2 detectors used in the LUCIFER and LINC-NIRVANA instruments for the Large Binocular Telescope (LBT). To fully exploit the capabilities of the LBT, the detector subsystem must meet, especially in the; case of the low background applications foreseen for LUCIFER, very stringent requirements in terms of stability and read noise. A read-out electronics has been developed at MPIA, which is able to read the 32 outputs of the Hawaii-2 detector, as well as the 4 reference signals available in this chip. The noise figure associated to the electronics alone is negligible with respect to the intrinsic read noise of the detector, while the cloking patterns and the value of the bias voltages applied to the chip are optimized in order to maximize the signal to noise ratio in the different operating modes. We present the results of the tests performed with the LUCIFER science detector; in particular, we describe the main properties of the detector: read noise, dark current, linearity, and long term stability, and what are the read-out schemes foreseen for different observational modes. We discuss also how the reference outputs can be used in order to correct for thermal drifts, and how effective those outputs are in removing higher frequency noise components.