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The microquasar V404 Cygni (also known as GS 2023+338) was previouslyreported to have weak GeV gamma-ray emission in sub-day time periods during its2015 outburst. In order to provide more detailed information at the high energyrange for this black hole binary system, we conduct analysis to the dataobtained with the Large Area Telescope (LAT) onboard the Fermi Gamma-ray SpaceTelescope (Fermi). Both LAT database and source catalog used are the latest. Inaddition to the previously reported detection at the peak of the 2015 outburst,we find possible detection ($\sim 4\sigma$) of the source during 3-day timeperiod of 2015 Aug. 17--19 (at the end of the 2015 outburst) and one convincingdetection ($\simeq 7\sigma$) in 2016 Aug. 23--25. The latter high-significancedetection shows that the gamma-ray emission of the source is soft with photonindex $\Gamma\sim 2.9$. As gamma-ray emission from microquasars is consideredto be associated with their jet activity, we discuss the results by comparingwith those well studied cases, namely Cyg X-3 and Cyg X-1. The detection helpsidentify V404 Cygni as a microquasar with detectable gamma-ray emission in itsquiescent state, and adds interesting features to the microquasar group, or ina more general context to X-ray binaries with jets.

Detection of the microquasar V404 Cygni at gamma-rays revisited: short flaring events in quiescence