E. Chabanat

Improved ion guide for heavy-ion fusion–evaporation reactions

The ion guide for heavy-ion-induced reactions developed originally for the SARA facility in Grenoble has been implemented at the Jyvaskyla IGISOL facility. For the Cd-116(Ar-40, 6n)Dy-150 reaction an efficiency of 0.5% relative to the number of reaction products entering the stopping chamber was obtained. This is 3.5 times higher than previously obtained at SARA and corresponds to a yield of about 100 ions/(p mu C mb). Mass-separated yields for the Ar-36 + Mo-92 and Ar-36 + Mo-94 reactions were measured

Impact of noise covariance and nonlinearities in NIR H2RG detectors

We characterize at pixel level a NIR H2RG detector read with SIDECAR ASIC, similar to the detectors used in Euclids Near IR Spectrometer Photometer (NISP). We derive the full covariance matrix formulae, extending the results from previous publications, and compare them to data and simulations for NISP baseline operating modes. The nonlinear response of the detector is measured and high precision maps are derived for in-flight or on-ground correction. High precision maps of the conversion gain are also determined using the Photon Transfer Curve technique.

Impact of common modes correlations and time sampling on the total noise of a H2RG near-IR detector

We present the readout noise reduction methods and the 1/f noise response of an 2K × 2K HgCdTe detector similar to the detectors that will be used in the Near Infrared Spectrometer Photometer - one of the instruments of the future ESA mission named Euclid. Various algorithms of common modes subtraction are defined and compared. We show that the readout noise can be lowered by 60% using properly the references provided within the array. A predictive model of the 1/f noise with a given frequency power spectrum is defined and compared to data taken in a wide range of sampling frequencies. In view of this model the definition of ad-hoc readout noises for different sampling can be avoided.

Single-photon sensitive fast ebCMOS camera system for multiple-target tracking of single fluorophores: application to nano-biophotonics

Nano-biophotonics applications will benefit from new fluorescent microscopy methods based essentially on super-resolution techniques (beyond the diffraction limit) on large biological structures (membranes) with fast frame rate (1000 Hz). This trend tends to push the photon detectors to the single-photon counting regime and the camera acquisition system to real time dynamic multiple-target tracing. The LUSIPHER prototype presented in this paper aims to give a different approach than those of Electron Multiplied CCD (EMCCD) technology and try to answer to the stringent demands of the new nano-biophotonics imaging techniques. The electron bombarded CMOS (ebCMOS) device has the potential to respond to this challenge, thanks to the linear gain of the accelerating high voltage of the photo-cathode, to the possible ultra fast frame rate of CMOS sensors and to the single-photon sensitivity. We produced a camera system based on a 640 kPixels ebCMOS with its acquisition system. The proof of concept for single-photon based tracking for multiple single-emitters is the main result of this paper.

Low noise flux estimate and data quality control monitoring in EUCLID-NISP cosmological survey

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.

A new 400 ms isomer in125Ce→125La

By using the IGISOL technique, adapted for the study of products of heavy ion induced fusion-evaporation reactions, it has been possible to identify a new isomer in the mass chainA=125.