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Recent studies have suggested that the short-timescale ($\lesssim7$ days)variability of the broad ($\sim$10,000 km s$^{-1}$) double-peaked H$\alpha$profile of the LINER nucleus of NGC1097 could be driven by a variable X-rayemission from a central radiatively inefficient accretion flow (RIAF). To testthis scenario, we have monitored the NGC1097 nucleus in X-ray and UV continuumwith Swift and the H$\alpha$ flux and profile in the optical spectrum usingSOAR and Gemini-South from 2012 August to 2013 February. During the monitoringcampaign, the H$\alpha$ flux remained at a very low level --- 3 times lowerthan the maximum flux observed in previous campaigns and showing only limited($\sim 20\%$) variability. The X-ray variations were small, only $\sim 13\%$throughout the campaign, while the UV did not show significant variations. Weconcluded that the timescale of the H$\alpha$ profile variation is close to thesampling interval of the optical observations, which results in only marginalcorrelation between the X-ray and H$\alpha$ fluxes. We have caught the AGN inNGC1097 in a very low activity state, in which the ionizing source was veryweak and capable of ionizing just the innermost part of the gas in the disk.Nonetheless, the data presented here still support the picture in which the gasthat emits the broad double-peaked Balmer lines is illuminated/ionized by asource of high-energy photons which is located interior to the inner radius ofthe line-emitting part of the disk.

Short-Timescale monitoring of the X-ray, UV and broad double-peak emission line of the nucleus of NGC 1097