Euclid Near Infrared Spectrometer and Photometer instrument concept and first test results obtained for different breadboards models at the end of phase C

Abstract

The Euclid mission objective is to understand why the expansion of the Universe is accelerating through by mapping the geometry of the dark Universe by investigating the distance-redshift relationship and tracing the evolution of cosmic structures. The Euclid project is part of ESA's Cosmic Vision program with its launch planned for 2020 (ref [1]). The NISP (Near Infrared Spectrometer and Photometer) is one of the two Euclid instruments and is operating in the near-IR spectral region (900-2000nm) as a photometer and spectrometer. The instrument is composed of: -a cold (135K) optomechanical subsystem consisting of a Silicon carbide structure, an optical assembly (corrector and camera lens), a filter wheel mechanism, a grism wheel mechanism, a calibration unit and a thermal control system -a detection subsystem based on a mosaic of 16 HAWAII2RG cooled to 95K with their front-end readout electronic cooled to 140K, integrated on a mechanical focal plane structure made with molybdenum and aluminum. The detection subsystem is mounted on the optomechanical subsystem structure -a warm electronic subsystem (280K) composed of a data processing / detector control unit and of an instrument control unit that interfaces with the spacecraft via a 1553 bus for command and control and via Spacewire links for science data This presentation describes the architecture of the instrument at the end of the phase C (Detailed Design Review), the expected performance, the technological key challenges and preliminary test results obtained for different NISP subsystem breadboards and for the NISP Structural and Thermal model (STM).

Laboratory Measurement of the Brighter-fatter Effect in an H2RG Infrared Detector

“…The detector tested in this experiment was an engineering-grade Teledyne H2RG-18 NIR detector (2048 2 pixels; 18 µm pitch) with a cutoff wavelength of 2.3 µm. The NIR detector working group for the Euclid mission lent the H2RG to the PPL for the purpose of investigating intra-pixel response variations, which impact the photometric accuracy of the Near Infrared Spectrophotometer (NISP; Maciaszek et al (2016); Prieto et al (2012)). That study will be presented in a separate paper.…”

The Euclid Near Infrared Spectro-Photometer (NISP) instrument and science

“…For the spectroscopic observation, the minimum flux for the detection is 2 × 10 −16 erg • s −1 • cm −2 , corresponding to ∼ 3.5σ SNR. In addition, photometric detection limit in NIR wavelengths for 5σ SNR point sources is of 24 AB magnitude [4]. The number of expected observed galaxies is 2.5 × 10 7 and 1.5 × 10 9 for the spectroscopic and the photometric sample, respectively.…”

“…The NISP functional architecture is shown in Figure 2. A more detailed description can be found in [4].…”

Detecting Solar system objects with convolutional neural networks

“…The Euclid payload consists of 2 instruments. VIS (Cropper et al 2016) will obtain high-resolution optical imaging and NISP (Maciaszek et al 2016) will provide photometry in three near-infrared bands as well as slit-less spectroscopy measurements.…”