论文标题
深入的CFHT光学搜索可能与可能的中子星 - 黑洞合并GW190814
A Deep CFHT Optical Search for a Counterpart to the Possible Neutron Star -- Black Hole Merger GW190814
论文作者
论文摘要
我们为可能的中子星 - 黑洞（NS-BH）合并GW190814/S190814BV提供了与可能中子星的电磁对应物进行的宽场光学成像搜索。通过LIGO/处女座干涉仪通过重力波检测到这种紧凑的二进制合并，质量暗示了NS-BH合并。我们使用加拿大 - 弗朗西·霍瓦伊望远镜上的Megacam仪器对Ligo/处女座定位区域进行了成像。我们描述了我们的混合观察策略，即瓷砖和星系靶向观测，以及我们的图像差异和瞬态检测管道。我们的观察运动在合并后1.7天至8.7天之间产生了该区域的一些最深的多频段图像，分别在1.7天达到了G> 22.8（AB MAG）的5sigma深度，而I> 23.1和I> 23.1和I> 23.9在3.7和8.7天。这些观察结果涵盖了平均总综合概率，为定位区域的67.0％。我们发现在图像中没有与此合并的引人注目的候选瞬态对应物，这表明要么较轻的物体在BH的最内向稳定的圆形轨道内部潮汐破坏，因此瞬态位于观察到的天空足迹之外，或者较轻的物体是低质量的BH。 We use 5sigma source detection upper limits from our images in the NS-BH interpretation of this merger to constrain the mass of the kilonova ejecta to be Mej < 0.015Msun for a 'blue' (kappa = 0.5 cm^2 g^-1) kilonova, and Mej < 0.04Msun for a 'red' (kappa = 5-10 cm^2 g^-1) kilonova.我们的观察结果强调了大孔径望远镜和宽场成像器（例如CFHT Megacam）在深入搜索电磁对应物到引力波事件时的关键作用。
We present a wide-field optical imaging search for electromagnetic counterparts to the likely neutron star - black hole (NS-BH) merger GW190814/S190814bv. This compact binary merger was detected through gravitational waves by the LIGO/Virgo interferometers, with masses suggestive of a NS-BH merger. We imaged the LIGO/Virgo localization region using the MegaCam instrument on the Canada-France-Hawaii Telescope. We describe our hybrid observing strategy of both tiling and galaxy-targeted observations, as well as our image differencing and transient detection pipeline. Our observing campaign produced some of the deepest multi-band images of the region between 1.7 and 8.7 days post-merger, reaching a 5sigma depth of g > 22.8 (AB mag) at 1.7 days and i > 23.1 and i > 23.9 at 3.7 and 8.7 days, respectively. These observations cover a mean total integrated probability of 67.0% of the localization region. We find no compelling candidate transient counterparts to this merger in our images, which suggests that either the lighter object was tidally disrupted inside of the BH's innermost stable circular orbit, the transient lies outside of the observed sky footprint, or the lighter object is a low-mass BH. We use 5sigma source detection upper limits from our images in the NS-BH interpretation of this merger to constrain the mass of the kilonova ejecta to be Mej < 0.015Msun for a 'blue' (kappa = 0.5 cm^2 g^-1) kilonova, and Mej < 0.04Msun for a 'red' (kappa = 5-10 cm^2 g^-1) kilonova. Our observations emphasize the key role of large-aperture telescopes and wide-field imagers such as CFHT MegaCam in enabling deep searches for electromagnetic counterparts to gravitational wave events.
