output
20152022
most citedChemical abundances in Seyfert galaxies -IX. Helium abundance estimates

24 citations

researchers with a paper here

Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.

collaborating institutions

5 papers

astro-ph.GA2022★ 12 cited

Chemical abundance of LINER galaxies -- Metallicity calibrations based on SDSS-IV MaNGA

C. B. Oliveira, A. C. Krabbe, J. A. Hernandez-Jimenez +5

The ionizing source of Low Ionization Nuclear Emission Regions (LINERs) is uncertain. Because of this, an empirical relation to determine the chemical abundances of these objects h…

astro-ph.GA2022★ 24 cited

Chemical abundances in Seyfert galaxies -IX. Helium abundance estimates

O. L. Dors, M. Valerdi, P. Freitas-Lemes +7

For the first time, the helium abundance relative to hydrogen (He/H), which relied on direct measurements of the electron temperature, has been derived in the narrow line regions (…

astro-ph.GA2021★ 8 cited

Chemical abundances in Seyfert galaxies -- VIII. Argon abundance estimates

A. F. Monteiro, O. L. Dors

For the first time, the argon abundance relative to hydrogen abundance (Ar/H) in the narrow line region of a sample of Seyfert 2 nuclei has been derived. In view of this, optical n…

eess.SP2018

Interval Simulation of Narmax Models Based on Computer Arithmetic

P. F. S. Guedes, M. L. C. Peixoto, O. A. R. O. Freitas +3

System identification is an important area of science, which aims to describe the characteristics of the system, representing them by mathematical models. Since many of these model…

astro-ph.HE2015

Finding AGN in Deep X-ray Flux States with Swift

Dirk Grupe, S. Komossa, Mason Bush +7

We report on our ongoing project of finding Active Galactic Nuclei (AGN) that go into deep X-ray flux states detected by Swift. Swift is performing an extensive study on the flux a…