The ECLAIRs GRB-trigger telescope on-board the future mission SVOM

TL;DR

The paper describes the ECLAIRs gamma-ray imager on the SVOM satellite, designed to detect and localize GRBs in real-time, enabling rapid follow-up observations and advancing gamma-ray burst research.

Contribution

It introduces the ECLAIRs instrument and its role in the SVOM mission for real-time GRB detection and localization.

Findings

ECLAIRs will detect GRBs in 4-120 keV range.

Real-time GRB alerts will be sent to ground.

The system enables rapid follow-up observations.

Abstract

The Space-based multi-band astronomical Variable Objects Monitor (SVOM) is an approved satellite mission for Gamma-Ray Burst (GRB) studies, developed in cooperation between the Chinese National Space Agency (CNSA), the Chinese Academy of Sciences (CAS), the French Space Agency (CNES) and French laboratories. SVOM entered Phase B in 2014 and is scheduled for launch in 2021. SVOM will provide fast and accurate GRB localizations, and determine the temporal and spectral properties of the GRB emission, thanks to a set of 4 on-board instruments. The trigger system of the coded-mask telescope ECLAIRs images the sky in the 4-120 keV energy range, in order to detect and localize GRBs in its 2 sr-wide field of view. The low-energy threshold of ECLAIRs is well suited for the detection of highly redshifted GRB. The high-energy coverage is extended up to 5 MeV thanks to the non-imaging gamma-ray spectrometer GRM. GRB alerts are sent in real-time to the ground observers community, and a spacecraft slew is performed in order to place the GRB within the field of view of the soft X-ray telescope MXT and the visible-band telescope VT, to refine the GRB position and study its early afterglow. The ground-based robotic telescopes GFTs and the wide angle cameras GWAC complement the on-board instruments. In this paper we present the ECLAIRs soft gamma-ray imager which will provide the GRB triggers on-board SVOM.