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Comparison of the X-ray and optical variabilities in the Seyfert galaxy 3C 120статья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
- Авторы: Doroshenko V.T., Sergeev S.G., Efimov Yu S., Klimanov S.A., Nazarov S.V.
- Журнал: Astronomy Letters
- Том: 35
- Номер: 6
- Год издания: 2009
- Издательство: Maik Nauka/Interperiodica Publishing
- Местоположение издательства: Russian Federation
- Первая страница: 361
- Последняя страница: 374
- DOI: 10.1134/S1063773709060012
- Аннотация: Based on our UBV RI observations and X-ray data from the RXTE satellite, we have investigated the variability of the galaxy 3C 120 over the period 1996-2008. The relative variability amplitude in the U and B bands without any subtraction of the contribution from the underlying galaxy is 23 and 22%, respectively, against 21% in the X-ray band. The autocorrelation function based on the B-band data is considerably wider than that based on the X-ray data. The structure functions on a time scale from 1 to ˜100-300 days in the X-ray and optical spectral ranges have the form of a power law ( SF ˜ τ b ). However, their indices differ significantly: b = 0.42 in the X-ray band and b = 1.36 in the B band. Considering the X-ray and optical variabilities as a superposition of independent flares in a wide range of durations, we may conclude that the amplitudes of short flares in the X-ray band are higher than those in the optical one and, conversely, the relative amplitudes of long flares in the X-ray band are slightly lower than those in the optical one, i.e., short events dominate in the X-ray band. The optical flux variations in the R c and I c bands lag significantly behind those in the B band, by 3.9{-0.7/+1.0} and 6.2{-0.6/+1.1} days, respectively, if the lag is estimated from the centroid of the cross-correlation function. The X-ray variability on a time scale of about 1800 days (˜5 yr) lags behind the B-band variations by 5.3{-3.3/+2.7} days, but the confidence level of this estimate is only 87%. A more detailed analysis of the correlation between the X-ray and optical emissions has revealed a fairly complex picture: different degrees of correlation between the optical and X-ray fluxes are observed at different times.
- Добавил в систему: Дорошенко Валентина Трофимовна