论文标题
SVOM/Eclairs图像触发具有基于小波的背景校正，并通过一年的观测模拟进行了优化
The SVOM/ECLAIRs image trigger with wavelet-based background correction optimised with a one-year simulation of observations
论文作者
论文摘要
正在开发的SVOM任务将携带四种乐器，尤其是编码遮罩望远镜，名为Eclairs，在4-150 KEV Energy Band运行，具有大约2 SR的巨大视野。船上的触发软件将搜索来自已知X射线源的高能量瞬变，例如伽马射线爆发和特殊的行为（例如，强烈爆发），以便将卫星重新点击以使用板载狭窄的视场进行后续观察。图像触发器是板上软件中实现的两种算法之一，在曝光期间产生图像，范围从20秒到20分钟，在此期间，地球可以越过视野。预计CXB和来自已知X射线源的贡献将主导着天体物理和仪器背景，并且必须在编码的遮罩图像反卷积之前考虑并进行校正，以优化对微弱瞬变的敏感性。为了纠正这些背景组件，我们实现并研究了一种基于检测器图像的小波分解的传统拟合方法和一种新方法。为了研究和评估这些方法的性能，我们对板上的图像触发器进行了为期一年的模拟。从SVOM任务的这种现实观察方案中产生的图像来看，我们还定义了一种分析天空图像以搜索新来源的方法。我们介绍了板SVOM/Eclairs上图像触发器背后的算法。我们表明，与传统拟合方法相比，我们实施的小波方法在清洁性能方面提供了相似的结果，并且有益于不需要对检测器背景形状的任何假设。我们还根据重建的天空图像的质量来校准检测阈值以自适应。
The SVOM mission under development will carry four instruments, and in particular the coded-mask telescope named ECLAIRs, with a large field of view of about 2 sr, operating in the 4-150 keV energy band. The trigger software on board ECLAIRs will search for high-energy transients such as gamma-ray bursts and peculiar behaviour (e.g. strong outbursts) from known X-ray sources, in order to repoint the satellite to perform follow-up observations with the onboard narrow field of view instruments. The image trigger, one of the two algorithms implemented in the software on board ECLAIRs, produces images over periods of exposure ranging from 20 seconds to 20 minutes during which the Earth can cross the field of view. The CXB and contributions from known X-ray sources are expected to dominate the ECLAIRs astrophysical and instrumental background and must be taken into account and corrected prior to coded-mask image deconvolution in order to optimise the sensitivity to faint transients. To correct these background components, we implemented and studied a traditional fitting method and a new method based on wavelet decomposition of the detector image. In order to study and to assess the performance of these methods, we performed a one-year simulation of the image trigger on board ECLAIRs. From the images produced during this realistic observation scenario of the SVOM mission, we also defined a way to analyse the sky images to search for new sources. We present the algorithms behind the image trigger on board SVOM/ECLAIRs. We show that the wavelet method we implemented provides similar results in terms of cleaning performance compared to the traditional fitting method, and has the benefit of not requiring any assumption on the shape of the background on the detector. We also calibrate the detection threshold to be adaptive and based on the quality of the reconstructed sky image.
