activity
20192026
most citedThe Eighteenth Data Release of the Sloan Digital Sky Surveys: Targeting and First Spectra from SDSS-V

282 citations · 369 across the 16 of their papers we have counts for

collaborators

16 papers

astro-ph.GA2026

Spatially resolved optical and mid-infrared spectroscopy of SDSS1335+0728: implications for the origin of the Ansky event

P. Sánchez-Sáez, M. Masterson, L. Hernández-García +25

The galaxy SDSS1335+0728 brightened abruptly in December 2019 (the Ansky event) and has since been confirmed as the host of extreme X-ray quasi-periodic eruptions (QPEs) of debated…

astro-ph.HE2026

Evidence for a Delayed UV Counterpart to X-ray Quasi-periodic Eruptions in Ansky

Hengxiao Guo, Zhen Yan, Ya-Ping Li +15

X-ray quasi-periodic eruptions (QPEs) represent a novel population of extreme, repeating nuclear transients whose physical origins remain debated. A defining characteristic of QPEs…

astro-ph.HE2026

A positive period derivative in the quasi-periodic eruptions of ZTF19acnskyy

Joheen Chakraborty, Saul A. Rappaport, Riccardo Arcodia +9

We report the first direct measurement of the period derivative in a quasi-periodic eruption (QPE), finding a smoothly increasing period with $\dot{P}\approx (1.7\pm 0.02)\times10^…

astro-ph.GA2025★ 2 cited

Changing-Look Active Galactic Nuclei in SDSS-V: Host-Galaxy Properties and Black-Hole Scaling Relations

Grisha Zeltyn, Benny Trakhtenbrot, Michael Eracleous +23

Changing-look active galactic nuclei (CL-AGNs) exhibit dramatic spectral variability on unexpectedly short timescales, challenging standard accretion flow models. Despite growing s…

astro-ph.HE2025★ 3 cited

NICER observations reveal doubled timescales in Ansky's quasi-periodic eruptions (QPEs)

L. Hernández-García, P. Sánchez-Sáez, J. Chakraborty +11

Quasi-periodic eruptions (QPEs) are recurring X-ray bursts originating from the vicinity of supermassive black holes, but their driving mechanisms remain under debate. This study a…

astro-ph.IM2025

ALeRCE light curve classifier: Tidal disruption event expansion pack

M. Pavez-Herrera, P. Sánchez-Sáez, L. Hernández-García +9

ALeRCE (Automatic Learning for the Rapid Classification of Events) processes the Zwicky Transient Facility (ZTF) alert stream in preparation for the Vera C. Rubin Observatory, clas…

astro-ph.HE2025

The GRACE project: Hard X-ray giant radio galaxies and their duty cycle

G. Bruni, F. Panessa, L. Bassani +14

The advent of new generation radio telescopes is opening new possibilities on the classification and study of extragalactic high-energy sources, specially the underrepresented ones…

astro-ph.GA2024★ 1 cited

AT 2021hdr: A candidate tidal disruption of a gas cloud by a binary super massive black hole system

L. Hernández-García, A. M. Muñoz-Arancibia, P. Lira +25

With a growing number of facilities able to monitor the entire sky and produce light curves with a cadence of days, in recent years there has been an increased rate of detection of…

astro-ph.HE2024★ 1 cited

GRB 240529A: A Tale of Two Shocks

Tian-Rui Sun, Jin-Jun Geng, Jing-Zhi Yan +66

Thanks to the rapidly increasing time-domain facilities, we are entering a golden era of research on gamma-ray bursts (GRBs). In this Letter, we report our observations of GRB 2405…

astro-ph.GA2024★ 19 cited

SDSS1335+0728: The awakening of a black hole

P. Sánchez-Sáez, L. Hernández-García, S. Bernal +22

The galaxy SDSS1335+0728, which had exhibited no prior optical variations during the preceding two decades, began showing significant nuclear variability in the Zwicky Transient Fa…

astro-ph.GA2024★ 7 cited

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…

astro-ph.GA2023★ 1 cited

Optical variability in Quasars: Scaling with black hole mass and Eddington ratio depend on the observed timescales

Patricia Arévalo, Paulina Lira, Paula Sánchez-Sáez +4

Quasars emission is highly variable, and this variability gives us clues to understand the accretion process onto supermassive black holes. We can expect variability properties to…

astro-ph.GA2023★ 282 cited

The Eighteenth Data Release of the Sloan Digital Sky Surveys: Targeting and First Spectra from SDSS-V

Andrés Almeida, Scott F. Anderson, Maria Argudo-Fernández +151

The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises three primary scientific progr…

astro-ph.GA2022★ 24 cited

Unexplored outflows in nearby low luminosity AGNs: the case of NGC 1052

S. Cazzoli, L. Hermosa Muñoz, I. Márquez +6

Outflows play a central role in galaxy evolution shaping the properties of galaxies. Understanding outflows and their effects in low luminosity AGNs, such as LINERs, is essential (…

astro-ph.GA2022★ 16 cited

Observational hints on the torus obscuring gas behaviour through X-rays with NuSTAR data

Natalia Osorio-Clavijo, Omaira González-Martín, Sebastián F. Sánchez-Sánchez +5

According to theory, the torus of active galactic nuclei (AGN) is sustained from a wind coming off the accretion disk, and for low efficient AGN, it has been proposed that such str…

astro-ph.GA2019★ 13 cited

The inner view of NGC 1052 using multiple X-ray observations

Natalia Osorio-Clavijo, Omaira González-Martín, Iossif Papadakis +2

In this paper, we make a multi-epoch analysis of NGC 1052, one of the prototypical LLAGN, using XMM-Newton, Suzaku and NuSTAR observations, taken from 2001 to 2017. This is the fir…