Apparent [O III] variability in the narrow line Seyfert I Mrk142

作者：Zhang, Xue Guang^*; Feng, Long Long

来源：Monthly Notices of the Royal Astronomical Society, 2016, 457(1): L64-L68.

DOI：10.1093/mnrasl/slv204

• galaxies: active
• galaxies: nuclei
• quasars: emission lines
• galaxies: Seyfert

In this Letter, we checked spectral properties of the well-known narrow line Seyfert I Mrk142, in order to try to find effects of narrow line variability on BLR radius of Mrk142 which is an outlier in the R-L plane. Although, no improvement can be found on BLR radius, apparent narrowline variability can be confirmed in Mrk142. Using the public spectra collected from the Lick AGN Monitoring Project, the spectral scaling method based on assumption of constant [O III] line is first checked by examining broad and narrow emission line properties. We find that with the application of the spectral scaling method, there is a strong correlation between the [OIII] line flux and the [OIII] line width, but weaker correlations between the broad Ha flux and the broad H beta flux, and between the broad Ha flux and the continuum emission at 5100 angstrom. The results indicate that the assumption of constant [O III] line is not preferred, and caution should be exercised when applying the spectral scaling calibration method. And then, we can find a strong correlation between the [OIII] line flux and the continuum emission at 5100 angstrom, which indicates apparent short-term variability of the [OIII] line in Mrk142 over about two months.

• 出版日期2016-3-21
• 单位中山大学