CAGIRE is the near infrared camera of the Colibrí robotic telescope, designed for the follow-up of SVOM alerts, mainly Gamma Ray Bursts (GRBs), and the quick imaging of sky regions where transient sources are detected by the SVOM satellite. CAGIRE is based on the Astronomical Large Format Array (ALFA) 2k x 2k SWIR sensor from the French consortium CEA-LYNRED. In the context of CAGIRE the sensor is operated in “Up the Ramp” mode to observe the sky in a square field of view of 21.7 arcmin on a side, in the range of wavelengths from 1.1 to 1.8 μm. An observation with CAGIRE consists of a series of short (1-2 minutes) exposures during which the pixels are read out every 1.3 second, continuously accumulating charges proportionally to the received flux, building a ramp.
The main challenge is to quickly process and analyse these ramps, in order to identify and study the near infrared counterparts of the bursts, within 5 minutes of the reception of an alert. Our preprocessing, which is under development, aims at providing reliable flux maps for the astronomy pipeline. It is based on a sequence of operations. First, calibration maps are used to identify saturated pixels, and for each pixel, the usable (non saturated) range of the ramp. Then, the ramps are corrected for the electronic common mode noise, and differential ramps are constructed. Finally, the flux is calculated from the differential ramps, using a previously calibrated map of pixel non-linearities. We present here the sequence of operations performed by the preprocessing, which are based on previous calibrations of the sensor response. These operations lead to the production of a flux map corrected from cosmic-rays hits, a map depicting the quality of the fit, a map of saturated pixels and a map of pixels hit by cosmic-rays, before the acquisition of the next ramp. These maps will be used by the astronomy pipeline to quickly extract the scientific results of the observations, like the identification of uncatalogued or quickly variable sources that could be GRB afterglows.
Euclid is a major ESA mission scheduled for launch in 2023-2024 to map the geometry of the dark Universe using two primary probes, weak gravitational lensing and galaxy clustering. Euclid’s instruments, a visible imager (VIS) and an infrared spectrometer and photometer (NISP) have both been designed and built by Euclid Consortium teams. The NISP instrument will hold a large focal plane array of 16 near-infrared H2RG detectors, which are key elements to the performance of the NISP, and therefore to the science return of the mission.
Euclid NISP H2RG flight detectors have been individually and thoroughly characterized at Centre de Physique des Particules de Marseille (CPPM) during a whole year with a view to producing a reference database of performance pixel maps. Analyses have been ongoing and have shown the relevance of taking into account spatial variations in deriving performance parameters. This paper will concentrate on interpixel capacitance (IPC) and conversion gain. First, per pixel IPC coefficient maps will be derived thanks to single pixel reset (SPR) measurements and a new IPC correction method will be defined and validated. Then, the paper will look into correlation effects of IPC and their impact on the derivation of per super-pixel IPC-free conversion gain maps. Eventually, several conversion gain values will be defined over clearly distinguishable regions.
The NISP (Near Infrared Spectrometer and Photometer) is one of the two Euclid instruments (see ref [1]). It operates in the near-IR spectral region (950-2020nm) as a photometer and spectrometer. The instrument is composed of: - a cold (135K) optomechanical subsystem consisting of a Silicon carbide structure, an optical assembly, a filter wheel mechanism, a grism wheel mechanism, a calibration unit and a thermal control system - a detection system based on a mosaic of 16 H2RG with their front-end readout electronic. - a warm electronic system (290K) 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 paper presents: - the final architecture of the flight model instrument and subsystems - the performances and the ground calibration measurement done at NISP level and at Euclid Payload Module level at operational cold temperature.
Euclid is an ESA mission to map the geometry of the dark Universe with a planned launch date in 2021. Euclid is optimised for two primary cosmological probes, weak gravitational lensing and baryonic acoustic oscillations. They are implemented through two science instruments on-board Euclid, a visible imager (VIS) and a near-infrared photometer/spectrometer (NISP), which are being developed and built by the Euclid Consortium instrument development teams. The NISP instrument contains a large focal plane assembly of 16 Teledyne HgCdTe H2RG detectors with 2.3 μm cut-off wavelength and SIDECAR readout electronics. The performance of the detector systems is critical for the science return of the mission and extended on-ground tests are being performed for characterisation and calibration purposes. Special attention is given also to effects even on the scale of individual pixels, which are difficult to model and calibrate, and to identify any possible impact on science performance. This paper discusses the known effect of random telegraph signal (RTS) in a follow-on study of test results from the Euclid NISP detector system demonstrator model [1], addressing open issues and focusing on an in-depth analysis of the RTS behaviour over the pixel population on the studied Euclid H2RGs.
Euclid is a major ESA mission for the study of dark energy planned to launch in 2021. Euclid will probe the expansion history of the Universe using weak lensing and baryonic acoustic oscillations probes. A survey of 15,000 deg2 of the sky with the instrument NISP (Near-Infrared Spectro-Photometer), in the 900 – 2100 nm band, will give both the photometric and spectrometric redshifts of tens of millions of galaxies. The 16 H2RG detectors of the NISP focal plane array are still being characterized at CPPM (Marseille). Already 16 out of 20 flight detectors have been tested and a straightforward analysis done. Performance of the dedicated test benches – in particular control of flux and temperature – as well as an overview of the test flow will be presented. This paper will present methods and some preliminary results on two detectors focusing on the determination of a per pixel conversion gain.
Euclid is an ESA mission to map the geometry of the Dark Universe with a planned launch date in 2021.1 Two
primary cosmological probes, weak gravitational lensing and baryonic acoustic oscillations, are implemented
through a VISible imager (VIS) and a Near-Infrared Spectrometer and Photometer (NISP).2 The ground characterization of the NISP Flight Sensor Chip Systems (SCS) followed by the pixel response calibration aims to
produce all informations to correct and control the accuracy of the signal. This work reports on the ground
characterization of the NISP detector chain. The detector and electrical effects are likely to generate statistical
fluctuations and systematic errors on the final flux measurement. The analysis strategies to maintain the pixel
relative response accuracy within 1% is proposed in this work. The Euclid NISP test ow is presented and
the main concerns of the detector chain calibration, such as non-linearity, charge trapping and de-trapping are
discussed on the basis of the analysis of the flight detectors characterization data.
Euclid is an ESA mission to map the geometry of the dark Universe with a planned launch date in 2020. Euclid is optimised for two primary cosmological probes, weak gravitational lensing and galaxy clustering. They are implemented through two science instruments on-board Euclid, a visible imager (VIS) and a near-infrared spectro-photometer (NISP), which are being developed and built by the Euclid Consortium instrument development teams. The NISP instrument contains a large focal plane assembly of 16 Teledyne HgCdTe H2RG detectors with 2.3μm cut-off wavelength and SIDECAR readout electronics. The performance of the detector systems is critical to the science return of the mission and extended on-ground tests are being performed for characterisation and calibration purposes. Special attention is given also to effects even on the scale of individual pixels, which are difficult to model and calibrate, and to identify any possible impact on science performance. This paper discusses a variety of undesired pixel behaviour including the known effect of random telegraph signal (RTS) noise based on initial on-ground test results from demonstrator model detector systems. Some stability aspects of the RTS pixel populations are addressed as well.
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).
Euclid mission is designed to understand the dark sector of the universe. Precise redshift measurements are provided by H2RG detectors. We propose an unbiased method of fitting the flux with Poisson distributed and correlated data, which has an analytic solution and provides a reliable quality factor - fundamental features to ensure the goals of the mission. We compare our method to other techniques of signal estimation and illustrate the anomaly detection on the flight-like detectors. Although our discussion is focused on Euclid NISP instrument, much of what is discussed will be of interest to any mission using similar near-infrared sensors.
In support of the European space agency (ESA) Euclid mission, NASA is responsible for the evaluation of the H2RG mercury cadmium telluride (MCT) detectors and electronics assemblies fabricated by Teledyne imaging systems. The detector evaluation is performed in the detector characterization laboratory (DCL) at the NASA Goddard space flight center (GSFC) in close collaboration with engineers and scientists from the jet propulsion laboratory (JPL) and the Euclid project. The Euclid near infrared spectrometer and imaging photometer (NISP) will perform large area optical and spectroscopic sky surveys in the 0.9-2.02 μm infrared (IR) region. The NISP instrument will contain sixteen detector arrays each coupled to a Teledyne SIDECAR application specific integrated circuit (ASIC). The focal plane will operate at 100K and the SIDECAR ASIC will be in close proximity operating at a slightly higher temperature of 137K. This paper will describe the test configuration, performance tests and results of the latest engineering run, also known as pilot run 3 (PR3), consisting of four H2RG detectors operating simultaneously. Performance data will be presented on; noise, spectral quantum efficiency, dark current, persistence, pixel yield, pixel to pixel uniformity, linearity, inter pixel crosstalk, full well and dynamic range, power dissipation, thermal response and unit cell input sensitivity.
The ESA mission Euclid is designed to explore the dark side of the Universe. The NISP (Near Infrared Spectro-
Photometer) is one of its two instruments operating in the near-IR spectral region (0.9-2μm), that will be fully integrated
and tested at Laboratory d’Astrophysique de Marseille (LAM) under vacuum and thermal conditions. The test campaign
will regroup functional tests, performance tests, calibration procedure validation and observations scenario test. One of
the main objectives of the test campaign will be the measurement of the focus position of NISP with respect to the
EUCLID object plane. To achieve these tests campaign, a global Ground Support Equipment (GSE) called the
Verification Ground System (VGS) has to be developed. It will be a complex set of GSE integrated in ERIOS chamber
made of: a telescope simulator to simulate the EUCLID telescope and to inject light into NISP, a thermal environment to
be used for NISP thermal balance and verification, a sets of mechanical interfaces to align all the parts into ERIOS
chamber, the NISP Electrical GSE (EGSE) to control the instrument during the test and a metrology system to measure
the positions of the components during the test. We will present the preliminary design and concepts of the VGS and we
will show the main difficulties we have to deal with: design of thermal environment at 80K with 4mK stability, the
development of a metrology system in vacuum, knowledge of the focus position within 150μm in cold, etc. The main
objectives of the NISP test will be explained and how the VGS responds to the test requirement.
Cleanliness specifications for infrared detector arrays are usually so stringent that effects are neglibile. However, the specifications determine only the level of particulates and areal density of molecular layer on the surface, but the chemical composition of these contaminants are not specified. Here, we use a model to assess the impact on system quantum efficiency from possible contaminants that could accidentally transfer or cryopump to the detector during instrument or spacecraft testing and on orbit operation. Contaminant layers thin enough to meet typical specifications, < 0.5μgram/cm2, have a negligible effect on the net quantum efficiency of the detector, provided that the contaminant does not react with the detector surface, Performance impacts from these contaminant plating onto the surface become important for thicknesses 5 - 50μgram/cm2. Importantly, detectable change in the ”ripple” of the anti reflection coating occurs at these coverages and can enhance the system quantum efficiency. This is a factor 10 less coverage for which loss from molecular absorption lines is important. Thus, should contamination be suspected during instrument test or flight, detailed modelling of the layer on the detector and response to very well known calibrations sources would be useful to determine the impact on detector performance.
Euclid, a major ESA mission for the study of dark energy, will offer a large survey of tens of millions of galaxies thanks to its Near-Infrared Spectro-Photometer. For it to be successful, the 16 Teledyne's 2.3 μm cutoff 2048x2048 pixels IR HgCdTe detectors of the focal plane must show very high performances over more than 95% of pixels, in terms of median dark current, total noise, budget error on non-linearity after correction, residual dark due to latency effects and quantum efficiency. This will be verified through a thorough characterization of their performances, leading to the production of the pixel map calibration database for the Euclid mission. Characterization is challenging in many ways: each detector will have to be fully and accurately characterized in less than three weeks, with rather tight requirements: dark current at the 10-3 e-/s level with 10% accuracy, relative Pixel Response map better than 1%, obtained with an illumination flatness better than 1%, measurements alternating dark and high level illumination taking care of latency impacts. Due to statistics needs, very long runs (24h without interrupts) of scripted measurements would be executed. Systematics of the test bench should be at the end the limiting factor of the parameter measurement accuracy. Test plan, facilities with functionalities developed for those specific purposes and associated performances will be described.
The detector system (DS) of Euclid NISP’s instrument (Near-Infrared Spectro-Photometer) is a matrix of 16 H2RG infrared detectors acquired simultaneously. After their characterization done at CPPM (Centre de Physique des Particules de Marseille), these detectors are integrated into a mechanical structure designed at LAM (Laboratoire d'Astronomie de Marseille) and called NI-FPA (Focal Plane Array) Before delivering the full instrument to ESA several test models have to demonstrate the performances of the detector system. The first test model, the Demonstrator Model (DM), has been integrated and tested in dedicated facilities at LAM. The aim was to validate both the integration process and the simultaneous acquisition of the detectors. Dark, noise, self-compatibility and EMC performances are presented in this paper.
The success of the Euclid's NISP (Near-Infrared Spectro-Photometer) instrument for the Euclid mission requires very high performance detectors for which tight specifications have been defined. These must be verified over more than 95% of the focal plane which is equipped with 16 H2RG infrared pixel detectors. Teledyne will provide these detectors and their electronics under ESA and NASA contracts. The detectors will be selected, qualified then delivered to the NISP instrument under Euclid specifications. To prepare the future calibration plan, these detectors must also be fully characterized at the pixel level before their integration. This characterization is crucial to the future processing and in-flight calibration. For a good control of the performance, the detector specifications for Euclid require in one hand to know some characteristics such as noise and dark current at a level as low as 10-3 e- /s , but also in other hand, require to have model of some specific properties of these detectors such as their non-linearity response, or their latency signals, which will imply specific measurements, characterization and studies. For this purpose, we have constructed dedicated facilities, and prepared a full test plan with adapted analysis methods and software tools that will be used to calibrate flight detectors. Here we describe the status of this plan, the facilities and their validation. We then present some preliminary results on dark current, total noise, CDS noise and some first estimations of persistence, using high performance engineering grade Euclid detectors provided by ESA. A pilot run is foreseen at the end of the year to validate the full test plan. Next step will be the characterization of flight detectors expected to start mid 2016.
The Euclid mission objective is to understand why the expansion of the Universe is accelerating 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.
The NISP (Near Infrared Spectro-Photometer) is one of the two Euclid instruments and is operating in the near-IR spectral region (0.9-2μm) as a
photometer and spectrometer. The instrument is composed of:
- a cold (135K) optomechanical subsystem consisting of a SiC 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 Teledyne 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 B (Preliminary Design Review), the expected performance, the
technological key challenges and preliminary test results obtained on a detection system demonstration model.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.