1570006

MAXI J1820+070 is a transient black hole X-ray binary (BHXRB) discovered by MAXI on March 11 2018. This outburst detected at almost any wavelength due to the low obscuration of the system is been monitored intensively by the astronomical community and so far has given rise to ~20 Astronomical Telegrams.Similarly to V404 Cyg the source displays intense flaring activity at almost any wavelength. But contrary to the highly absorbed V404 Cyg MAXI J1820+070 is an ideal candidate to understand the correlations between variability across the electromagnetic spectrum and therefore put stronger constraints in the relations between the physical phenomena producing emission in the different energy ranges and to study their variations on the different accretion regimes.The rise of the outburst has been monitored by INTEGRAL since March 16th 2018. Unfortunately the ongoing program will end by March 31st 2018. With this request and as a service to the community we propose to continue monitoring MAXI J1820+070 every single revolution with a 50 ksec exposure. With the current source flux around 3 Crab this will allow the generation of X-ray spectra of good enough S/N to characterise the system high energy emission and monitor variations of its slope indicative of spectral changes. As the source is not heavily absorbed in soft X-rays we request the observations to be performed in an HEX pattern in order to obtain continuous coverage with JEMX and be able to monitor as well variations in its soft X-ray emission.When the source flux decays below 50mCrab we propose to double the exposure to 100mCrab. We propose to continue this plan until the source reaches the quiescent state which we expect to happen in about 3 weeks.We will be in close communication with ISOC to provide feedback on the source flux so that the observing strategy can be modified when necessary. [truncated! Please see actual data for full text]

MAXI J1820+070是2018年3月11日由MAXI发现的瞬态黑洞X射线双星（Black Hole X-ray Binary, BHXRB）。该源因自身系统消光极低，几乎全波段均可被探测到，已被天文学界密集监测，截至目前已催生约20篇《天文电报（Astronomical Telegrams）》报道。与V404 Cyg类似，该源在几乎全波段均表现出强烈的耀发活动；但与消光极强的V404 Cyg不同，MAXI J1820+070是研究电磁波谱各波段变率相关性的理想候选体，借此可更严格地约束不同能量范围辐射产生的物理现象间的关联，并探究其在不同吸积状态下的演化规律。国际伽马射线天体物理实验室（INTEGRAL）自2018年3月16日起便对此次爆发开展了监测，但遗憾的是，该进行中的观测项目将于2018年3月31日结束。基于本次申请并作为对学界的服务支持，我们提议以每轨一次、每次曝光50千秒的频率持续监测MAXI J1820+070。鉴于当前源的流量约为3蟹状星云（Crab），此举将可获取信噪比足够高的X射线光谱，以准确表征该源的高能辐射特征，并监测指示光谱变化的谱指数演化。由于该源在软X射线波段消光程度较低，我们提议采用HEX观测模式开展观测，以获取JEMX的连续覆盖数据，同时亦可同步监测其软X射线辐射的变化。当该源的流量衰减至50毫蟹状星云（mCrab）以下时，我们提议将曝光时长翻倍至100千秒。我们将持续执行该观测计划，直至该源进入宁静态，我们预计这将在约3周内发生。我们将与ISOC保持密切沟通，实时反馈源的流量情况，从而在必要时灵活调整观测策略。【文本已截断！完整内容请查阅原始数据】