65 research outputs found
Fantastic Fits with fantasy of Active Galactic Nuclei Spectra -- Exploring the Fe II emission near the H line
In this study, a refined approach for multicomponent fitting of active
galactic nuclei (AGN) spectra is presented utilizing the newly developed Python
code (fully automated python tool for AGN spectra analysis). AGN
spectra are modeled by simultaneously considering the underlying broken
power-law continuum, predefined emission line lists, and an Fe II model, which
is here extended to cover the wavelength range 3700 - 11000 A. The Fe II model,
founded solely on atomic data, effectively describes the extensive emission of
the complex iron ion in the vicinity of the H and H lines, as
well as near the H line, which was previously rarely studied. The
proposed spectral fitting approach is tested on a sample of high-quality AGN
spectra from the Sloan Digital Sky Survey (SDSS) Data Release 17. The results
indicate that when Fe II emission is present near H, it is also detected
redward from H, potentially contaminating the broad H line
wings and thus affecting the measurements of its flux and width. The production
of Fe II emission is found to be strongly correlated with Eddington luminosity
and appears to be controlled by the similar mechanism as the hydrogen Balmer
lines. The study highlights the benefits of fitting AGN type 1 spectra with the
code, pointing that it may be used as a robust tool for analyzing a
large number of AGN spectra in the coming spectral surveys.Comment: Accepted in ApJ
Leadership in Multi-Space Offices: Realizing the Potential of Modern and Flexible Workplace Concepts
This chapter discusses the challenges for managers resulting from modern and flexible workplace concepts. It will specifically reflect on stressors that arise for employees when working in a multi-space environment and how employees bind to their workplace. Using a combined methodological approach, which integrates a literature review with the experiences of our daily work as workplace change consultants, managers receive concrete advice on how to lead in multi-space. This article thus aims to reduce the uncertainties and stressors triggered by New Work environments, or even to convert these into growth potential for the entire company, by naming concrete leadership measures based on values formulation and emotional leadership
The intrinsic Baldwin effect in broad Balmer lines of six long-term monitored AGNs
We investigate the intrinsic Baldwin effect (Beff) of the broad H and
H emission lines for six Type 1 active galactic nuclei (AGNs) with
different broad line characteristics: two Seyfert 1 (NGC 4151 and NGC 5548),
two AGNs with double-peaked broad line profiles (3C 390.3 and Arp 102B), one
narrow line Seyfert 1 (Ark 564), and one high-luminosity quasar with highly red
asymmetric broad line profiles (E1821+643). We found that a significant
intrinsic Beff was present in all Type 1 AGNs in our sample. Moreover, we do
not see strong difference in intrinsic Beff slopes in different types of AGNs
which probably have different physical properties, such as inclination, broad
line region geometry, or accretion rate. Additionally, we found that the
intrinsic Beff was not connected with the global one, which, instead, could not
be detected in the broad H or H emission lines. In the case of
NGC 4151, the detected variation of the Beff slope could be due to the change
in the site of line formation in the BLR. Finally, the intrinsic Beff might be
caused by the additional optical continuum component that is not part of the
ionization continuum.Comment: 12 pages, 8 figures, Accepted for publication in A&
Broad emission lines variability: a window into the heart of AGN
The broad emission lines of active galactic nuclei (AGN) are known to vary both in flux and shape, and are often showing very complex line profiles. They can give us invaluable information about the kinematics and geometry of the broad line region (BLR) where these lines are originating from. The BLR is close to the supermassive black hole in AGN and may hold basic information about the formation and fueling of AGN.
Here we summarize the results of the line and continuum variability of a sample of broad line AGN, obtained with the long-term optical monitoring campaign performed with telescopes of SAO (Russia), OAGH and OAN-SPM (Mexico), and Calar Alto (Spain). We monitored different type of broad line AGN (double-peaked, radio loud and radio quiet, NLSy1 and a supermassive binary black hole candidate) which show different variability characteristics that can be explained by different physical properties in BLR
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