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Description
As a result of the next cycle of our long-term monitoring, we present our UBV JHKLM photometry for the symbiotic nova V1016 Cyg in 2008-2014. The star continued to systematically fade and redden in UBV: over this period, the brightness declined by 0.1m in V and by 0.2m in B and U ,the B-V color index increased by 0.1m, and U-B barely changed. On the color-color (U-B, B-V) diagram, the star moved approximately horizontally rightward with a slight bluing in U-B starting from 2000. Our JHKLM photometry has shown a decline in the mean infrared (IR) brightness and a rise in the mean IR color indices after 2004 due to an increase in the optical depth of the dust envelope. The brightness decline and reddening of the Mira in the near infrared reached their extreme values over the entire period of the system's observations by the end of 2014. The pulsation period of the Mira is determined with confidence: P=465+/-5-days. The distance to the Mira, D=2.92+/-0.16kpc, ant its parameters, the radius R*=(470+/-50)R_{sun}_ and luminosity L*=(9200+/=1900)L_{sun}_, have been estimated from the observations of V1016 Cyg at its maximum J brightness and at its minimum J-H color index. The temperature of the star during its pulsations varied within the range T* =2100-2700K. We have estimated the parameters of the dust envelope near its maximum (in 2004) and minimum (in 2012-2014) IR brightness. The mass of the dust envelope almost doubled in ten years, with the rate of dust supply being {Delta}Md~10^-7^M_{sun}_/yr. Using a low-resolution spectrograph, we performed absolute spectrophotometry for V1016 Cyg in 1995-2013 in the range {lambda}4340-7130{AA}. We have shown that almost all absolute fluxes in lines and in continuum at {lambda}4400{AA} decrease monotonically after 2000, while the relative intensities of [OIII], [FeVII], and [CaVII] lines increase after the minimum that probably occurred in the 1990s. The significant (approximately by a factor of 10 from 1995 to 2013) decrease of the flux in the Raman OVI {lambda}6825 line reflects a change of conditions in the formation zone of this line due to the absorption of some OVI {lambda}1032 photons in the newly forming dust envelope of the cool component.
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