50 citations · 357 across the 19 of their papers we have counts for
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HALO II: Constraining Hubble constant through continuum delay fitting of Fairall 9
Amit Kumar Mandal, Francisco Pozo Nuñez, Vikram Kumar Jaiswal +28
The Hubble tension remains one of the most significant unresolved problems in modern cosmology. A key question is whether it may arise from underestimated systematic uncertainties…
A Newborn AGN in a Starforming Galaxy
P. Arévalo, E. López-Navas, M. L. Martínez-Aldama +8
We report on the finding of a newborn AGN, i.e. current AGN activity in a galaxy previously classified as non-active, and characterize its evolution. Black hole ignition event cand…
New theoretical Fe II templates for bright quasars
Ashwani Pandey, Mary Loli Martínez-Aldama, Bożena Czerny +5
We present a set of new theoretical Fe II templates for bright quasars covering a wavelength range of 1000-10000 Å\, based on the recent atomic database available in the C23.00 ver…
Exploring Changing-look Active Galactic Nuclei with the Sloan Digital Sky Survey V: First Year Results
Grisha Zeltyn, Benny Trakhtenbrot, Michael Eracleous +32
"Changing-look" active galactic nuclei (CL-AGNs) challenge our basic ideas about the physics of accretion flows and circumnuclear gas around supermassive black holes. Using first-y…
UV Fe II emission model of HE 0413-4031 and its relation to broad-line time delays
Michal Zajaček, Swayamtrupta Panda, Ashwani Pandey +11
Fe II emission is a well-known contributor to the UV spectra of active galactic nuclei and the modeling of this part may affect the results obtained for the MgII emiss…
The Sloan Digital Sky Survey Reverberation Mapping Project: Investigation of Continuum Lag Dependence on Broad-Line Contamination and Quasar Properties
Hugh W. Sharp, Y. Homayouni, Jonathan R. Trump +16
This work studies the relationship between accretion-disk size and quasar properties, using a sample of 95 quasars from the SDSS-RM project with measured lags between the and $…
Improving the selection of changing-look AGNs through multi-wavelength photometric variability
E. López-Navas, P. Sánchez-Sáez, P. Arévalo +13
We present second epoch optical spectra for 30 changing-look (CL) candidates found by searching for Type-1 optical variability in a sample of active galactic nuclei (AGNs) spectros…
Effect of extinction on quasar luminosity distances determined from UV and X-ray flux measurements
Michal Zajaček, Bożena Czerny, Narayan Khadka +4
In Khadka et al. (2023), a sample of X-ray-detected reverberation-mapped quasars was presented and applied for the comparison of cosmological constraints inferred using two well-es…
Accretion disks, quasars and cosmology: meandering towards understanding
Bozena Czerny, Shulei Cao, Vikram Kumar Jaiswal +11
As Setti & Woltjer noted back in 1973, quasars could be used to construct the Hubble diagram but the actual application was not that straightforward. It took years to implement the…
Confirming new changing--look AGNs discovered through optical variability using a random-forest based light curve classifier
E. López-Navas, M. L. Martínez-Aldama, S. Bernal +6
Determining the frequency and duration of changing--look (CL) active galactic nuclei (AGNs) phenomena, where the optical broad emission lines appear or disappear, is crucial to und…
Spectropolarimetry and spectral decomposition of high-accreting Narrow Line Seyfert 1 galaxies
Marzena Śniegowska, Swayamtrupta Panda, Bożena Czerny +7
Narrow Line Seyfert 1 (NLSy1) galaxies have been shown to have high Eddington ratios and relatively small black hole masses. The measurement of the black hole masses is based on th…
Quasars from LSST as dark energy tracers: first steps
Mary Loli Martínez-Aldama, Swayamtrupta Panda, Bożena Czerny +1
In the near future, new surveys promise a significant increase in the number of quasars (QSO) at large redshifts. This will help to constrain the dark energy models using quasars.…
Low ionization lines in high luminosity quasars: The calcium triplet
Mary Loli Martínez-Aldama, Deborah Dultzin, Paola Marziani +4
In order to investigate where and how low ionization lines are emitted in quasars we are studying a new collection of spectra of the CaII triplet at 8498, 8542, 8662 obser…