A new reverberation mapping campaign on NGC 5548

Here we report results from a new observational campaign between 2015 January and July. We measure the centroid time lag of the broad H{beta} emission line with respect to the 5100{AA} continuum and obtain {tau}_cent_=7.20_-0.35_^+1.33^days in the rest frame.

This yields a black hole mass of M.=8.71_-2.61_^+3.21^x10^7^M_{sun}_ using a broad H{beta} line dispersion of 3124+/-302km/s and a virial factor of f_BLR_=6.3+/-1.5 for the broad-line region (BLR), consistent with the mass measurements from previous H{beta} campaigns. The high-quality data allow us to construct a velocity-binned delay map for the broad H{beta} line, which shows a symmetric response pattern around the line center, a plausible kinematic signature of virialized motion of the BLR.