53 citations · 291 across the 12 of their papers we have counts for
12 papers
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…
The universal power spectrum of Quasars in optical wavelengths: Break timescale scales directly with both black hole mass and accretion rate
P. Arevalo, E. Churazov, P. Lira +5
Aims: Establish the dependence of variability properties, such as characteristic timescales and variability amplitude, on basic quasar parameters such as black hole mass and accret…
Persistent and occasional: searching for the variable population of the ZTF/4MOST sky using ZTF data release 11
P. Sánchez-Sáez, J. Arredondo, A. Bayo +13
We present a variability, color and morphology based classifier, designed to identify transients, persistently variable, and non-variable sources, from the Zwicky Transient Facilit…
Multiwavelength monitoring of the nucleus in PBC J2333.9-2343: the giant radio galaxy with a blazar-like core
L. Hernández-García, F. Panessa, G. Bruni +12
PBC J2333.9-2343 is a giant radio galaxy at z = 0.047 with a bright central core associated to a blazar nucleus. If the nuclear blazar jet is a new phase of the jet activity, then…
A Complex Quasi-Newton Proximal Method for Image Reconstruction in Compressed Sensing MRI
Tao Hong, Luis Hernandez-Garcia, Jeffrey A. Fessler
Model-based methods are widely used for reconstruction in compressed sensing (CS) magnetic resonance imaging (MRI), using regularizers to describe the images of interest. The recon…
A closer look at NGC 7314 nuclear region: a multiwavelength analysis of the Seyfert nucleus and its surroundings
Patrícia da Silva, R. B. Menezes, Y. Díaz +4
The central regions of galaxies harbouring active galactic nuclei (AGNs) can be quite complex, especially at high activity, presenting, besides variability, a variety of phenomena…
The Type 1 and Type 2 AGN dichotomy according to their ZTF optical variability
E. López-Navas, P. Arévalo, S. Bernal +4
The scarce optical variability studies in spectrally classified Type 2 active galactic nuclei (AGNs) have led to the discovery of anomalous objects that are incompatible with the s…
Constraining the X-ray reflection in low accretion rate AGN using XMM-Newton, NuSTAR and Swift
Y. Díaz, L. Hernández-García, P. Arévalo +8
An interesting feature in active galactic nuclei (AGN) accreting at low rate is the weakness of the reflection features in their X-ray spectra, which can result from the gradual di…
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…
Searching for changing-state AGNs in massive datasets -- I: applying deep learning and anomaly detection techniques to find AGNs with anomalous variability behaviours
P. Sánchez-Sáez, H. Lira, L. Martí +14
The classic classification scheme for Active Galactic Nuclei (AGNs) was recently challenged by the discovery of the so-called changing-state (changing-look) AGNs (CSAGNs). The phys…
Restarting activity in the nucleus of PBC J2333.9-2343: an extreme case of jet realignment
L. Hernández-García, F. Panessa, M. Giroletti +8
PBC J2333.9-2343 is a giant radio galaxy which shows different characteristics at different wavebands that are difficult to explain within the actual generic schemes of unification…
X-ray spectral variability of Seyfert 2 galaxies
L. Hernández-García, J. Masegosa, O. González-Martín +1
Variability across the electromagnetic spectrum is a property of AGN that can help constraining the physical properties of these galaxies. This is the third of a serie of papers wi…