Kovačević, J., Popovic, L. Č., Kollatschny, W., Saikia, P.

In order to understand physical and kinematical properties of AGN emission regions we investigate the correlations between different spectral properties.

In previuos work we found: - kinematical linkage between optical Fe II lines and Intermediate Line

Region (ILR), which indicates the ILR origin of optical Fe II. - different correlations between EWs of lines (and line components) vs.

Lcont.

- different correlations between spectral properties in “pure AGN” sample, and composit objects (AGN + starburst) sample, which indicates different physical processes in emission regions.

- etc... (Kovačević et al. 2010, Popović et al. 2011)

Present work: extension of research to UV part of spectra! GOAL: to compare UV and optical spectral properties (specially UV Fe

II lines with optical Fe II, in order to find location of their emission region, etc.)

1 step: determination of the UV pseudocontinuum in the sample!

Not easy because: 1. complex shape of UV pseudocontinuum: Power low + Balmer continuum (Grandi 1982)

Tsuzuki et al. 2006

2. Our sample contains spectra within spectral range: 2900 A – 5500 A (SDSS)(only two continuum windows : ~4200 A and ~5100A! Complex shape of UV pseudocontinuum cannot be fitted well!

Sameshima et al. 2010

Tsuzuki et al. 2006,Sameshima et al. 2010

Convolving Balmer continuum equation with Gaussian (FWHM Gaussian = FWHM broad Hβ)

Jin et al. 2012

We try to make model which: - we could use for fitting spectra within 2900 A – 5500 A range (with

two continuum windows). It could be done by reducing number of free parameters: calculating the intensity of Balmer continuum!

- we try to make good fit near Balmer edge (3646 A)!

Our model consists of: Power law + Balmer continuum (λ<3646A) + high order Balmer lines

(n=3-400), (λ>3646A)

They are fitted by one Gaussian with the same width and shift as Hγ.The relative intensites for Balmer lines with n<50 are taken from the paper: Storey and Hummer 1995. Relative intensities for 50<n<400 are calculated using approximate formula:

≈1

3000 A

The intensity of Balmer continuum near Balmer edge (~3646A) may be well estimated using fitting result for intensity of prominant Balmer lines (for example Hγ).

Model with high order Balmer lines n=3-400, for λ>3646A, improve the fit near Balmer edge.

Majority of analysed spectra have pseudocontinuum window at ~3000 A.

Calculated intensity of Balmer continuum, as well as one more continuum window (~3000A) should enable determination of UV pseudocontinuum in 2900 A – 5500 A range.

Future work: construction UV Fe II template, analysis of relationships between UV/optical spectral parameters...

Thank you for your attention!