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Chromospheric activity cycles are often found in old stars comma but their coronal X- ray counterparts have been difficult to catch. Thanks to XMM-Newton comma X-ray cycles have been detected in four stars comma moving forward an exploration of the parameters space of dynamo cycles openParactivity level comma cycle length comma etc.closePar. Two stars with known X-ray activity cycles are relatively young openPar500MyrclosePar comma rising the question at what age and activity level X-ray cycles set in. We propose here 4 short openPar6ksecclosePar observations of Kepler63. It is younger openPar250MyrclosePar comma has higher activity openParlogLx=29.02CORCHETE_OPENerg-sCORCHETE_CLOSEclosePar and a shorter cycle openPar1.27yrclosePar that the previous targets for such dedicated studies. A single XMM-Newton observing season can cover 1-2 of a full cycle with short snapshots.

色球活动周期在老年恒星中已被广泛观测到，但其对应的冕层X射线活动周期却始终难以被捕捉到。得益于XMM-牛顿（XMM-Newton）望远镜的观测，研究人员已在4颗恒星中探测到X射线活动周期，推动了对发电机周期参数空间（包括活动水平、周期长度等）的探索。目前已探明X射线活动周期的2颗恒星相对年轻（约5亿年），这引出了一个核心问题：X射线活动周期究竟在恒星达到何种年龄与活动水平时开始显现。我们在此提议对开普勒63（Kepler 63）开展4次时长为6千秒的短时间观测。该恒星更为年轻（约2.5亿年），活动水平更高（log Lₓ=29.02 erg·s⁻¹），且其活动周期仅为1.27年，短于此前此类专项研究的目标恒星。单个XMM-牛顿观测季即可通过数次短时间快照，覆盖其完整周期的1至2个阶段。