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We present the results of a two-year long optical monitoring program of thenarrow-line Seyfert 1 galaxy Akn 564. The majority of this monitoring projectwas also covered by X-ray observations (RXTE) and for a period of ~50 days, weobserved the galaxy in UV (HST) and X-rays (RXTE & ASCA) simultaneously withthe ground-based observations. Rapid and large-amplitude variations seen in theX-ray band, on a daily and hourly time-scale, were not detected at optical andUV wavelengths, which in turn exhibited much lower variability either on short(one day) or long (several months) time-scales. The only significant opticalvariations can be described as two 2--4 day events with ~10% flux variations.We detect no significant optical line variations and thus cannot infer areverberation size for the broad-line region. Similarly, the large X-rayvariations seem to vanish when the light curve is smoothed over a period of 30days. The UV continuum follows the X-rays with a lag of ~0.4 days, and theoptical band lags the UV band by ~2 days. No significant correlation was foundbetween the entire X-ray dataset and the optical band. Focusing on a 20-dayinterval around the strongest optical event we detect a significantX-ray--optical correlation with similar events seen in the UV and X-rays. Ourdata are consistent with reprocessing models on the grounds of the energyemitted in this single event. However, several large X-ray flares produced nocorresponding optical emission.Comment: 10 pages, 6 figures included, LaTeX emulateapj5.sty, accepted for  publication in The Astrophysical Journa

Multiwavelength Monitoring of the Narrow‐Line Seyfert 1 Galaxy Arakelian 564. III. Optical Observations and the Optical–UV–X‐Ray Connection