888 citations · 1.8k across the 27 of their papers we have counts for
27 papers
Large-amplitude modulations and hours-timescale variability in the early X-ray light curve of a tidal disruption flare
A. Malyali, A. Rau, P. Baldini +11
We present new X-ray, optical, and UV observations of the tidal disruption event candidate eRASSt J234402.9-352640, (hereafter J2344). Between 50 and 60 days after peak optical bri…
Optical and cm follow-ups of the Changing-Look event in Mkn 590
Biswaraj Palit, Abhijeet Borkar, Agata Różańska +5
The Changing-Look active galactic nucleus Mkn 590 is currently in a rejuvenated state, exhibiting a contemporaneous flux rise across X-rays, UV, optical and cm wavelengths. In this…
Counterpart identification and classification for eRASS1 and characterisation of the AGN content
M. Salvato, J. Wolf, T. Dwelly +44
[abridged] Accurately accounting for the AGN phase in galaxy evolution requires a large, clean AGN sample. This is now possible with SRG/eROSITA. The public Data Release 1 (DR1, Ja…
BlazEr1: The eROSITA Blazar Catalog. Blazars and Blazar Candidates in the First eROSITA Survey
S. Haemmerich, A. Gokus, F. McBride +28
Aims. eROSITA, on board the Spectrum Roentgen Gamma (SRG) spacecraft, performed its first X-ray all-sky survey (eRASS1) between December 2019 and June 2020. It detected about 93000…
A new Bowen Fluorescence Flare and Extreme Coronal Line Emitter discovered by SRG/eROSITA
Pietro Baldini, Arne Rau, Riccardo Arcodia +19
The nuclear transient eRASSt J012026.5-292727 (J012026 hereafter) was discovered in the second SRG/eROSITA all-sky survey (eRASS2). The source appeared more than one order of magni…
Long Term Reverberation Mapping of Iron Coronal Lines in MKN 110
Charles Yin, Andy Lawrence, Martin Ward +2
We present flux measurements of the coronal lines [Fe VII] and [Fe X] spanning three decades, in the highly variable Active Galactic Nucleus (AGN) MKN 110. These coronal lines are…
Discovery of extreme Quasi-Periodic Eruptions in a newly accreting massive black hole
Lorena Hernández-García, Joheen Chakraborty, Paula Sánchez-Sáez +27
Quasi-periodic eruptions (QPEs) are rapid, recurring X-ray bursts from supermassive black holes, believed to result from interactions between accretion disks and surrounding matter…
eRO-ExTra: eROSITA extragalactic non-AGN X-ray transients and variables in eRASS1 and eRASS2
Iuliia Grotova, Arne Rau, Mara Salvato +19
(Abridged) While previous X-ray studies showed the dominance of regular active galactic nuclei (AGN) variability, a small fraction of sources arise from more exotic phenomena such…
An X-ray flaring event and a variable soft X-ray excess in the Seyfert LCRS B040659.9-385922 as detected with eROSITA
S. Krishnan, A. G. Markowitz, M. Krumpe +13
Extreme continuum variability in AGNs can indicate extreme changes in accretion flows onto supermassive black holes. We explore the multiwavelength nature of a continuum flare in t…
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…
The eROSITA Upper Limits: Description and access to the data
D. Tubín-Arenas, M. Krumpe, G. Lamer +13
The soft X-ray instrument eROSITA on board the Spectrum-Roentgen-Gamma (SRG) observatory has successfully completed four of the eight planned all-sky surveys, detecting almost one…
A radio flare associated with the nuclear transient eRASSt J234403-352640: an outflow launched by a potential tidal disruption event
A. J. Goodwin, G. E. Anderson, J. C. A. Miller-Jones +7
We present an extensive radio monitoring campaign of the nuclear transient eRASSt J234403-352640 with the Australia Telescope Compact Array, one of the most X-ray luminous TDE cand…
The SRG/eROSITA all-sky survey: First X-ray catalogues and data release of the western Galactic hemisphere
A. Merloni, G. Lamer, T. Liu +142
The eROSITA telescope array aboard the Spektrum Roentgen Gamma (SRG) satellite began surveying the sky in December 2019, with the aim of producing all-sky X-ray source lists and sk…
Rapid evolution of the recurrence time in the repeating partial tidal disruption event eRASSt J045650.3-203750
Zhu Liu, Taeho Ryu, A. J. Goodwin +8
In this letter, we present the results from further X-ray and UV observations of the nuclear transient eRASSt J045650.3-203750 (hereafter J0456-20). We detected five repeating X-ra…
eROSITA Detection of a Cloud Obscuration Event in the Seyfert AGN EC 04570-5206
Alex Markowitz, Mirko Krumpe, David Homan +13
Recent years have seen broad observational support for the presence of a clumpy component within the circumnuclear gas around SMBHs. In the X-ray band, individual clouds can manife…
Multiwavelength study of extreme variability in LEDA 1154204: A changing-look event in a type 1.9 Seyfert
T. Saha, A. Markowitz, D. Homan +16
Context. Multiwavelength studies of transients in actively accreting supermassive black holes have revealed that large-amplitude variability is frequently linked to significant cha…
Still alive and kicking: A significant outburst in changing-look AGN Mrk 1018
R. Brogan, M. Krumpe, D. Homan +13
Changing-look active galactic nuclei (CL-AGN) have been observed to change optical spectral type. Mrk 1018 is unique: first classified as a type 1.9 Seyfert galaxy, it transitioned…
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…
Discovery of the luminous X-ray ignition eRASSt J234402.9352640; I. Tidal disruption event or a rapid increase in accretion in an active galactic nucleus?
D. Homan, M. Krumpe, A. Markowitz +17
In November 2020, a new, bright object, eRASSt J234402.9352640, was discovered in the second all-sky survey of SRG/eROSITA. The object brightened by a factor of at least 150 in…
The rebrightening of a ROSAT-selected tidal disruption event: repeated weak partial disruption flares from a quiescent galaxy?
A. Malyali, Z. Liu, A. Rau +11
The ROSAT-selected tidal disruption event (TDE) candidate RX J133157.6-324319.7 (J1331), was detected in 1993 as a bright (0.2-2 keV flux of erg s$^…
eRASSt J074426.3+291606: prompt accretion disc formation in a 'faint and slow' tidal disruption event
A. Malyali, Z. Liu, A. Merloni +10
We report on multi-wavelength observations of the tidal disruption event (TDE) candidate eRASSt J074426.3+291606 (J0744), located in the nucleus of a previously quiescent galaxy at…
The long-term broad-line responsivity in MKN 110
D. Homan, A. Lawrence, M. Ward +7
We examine the long-term history of the optical spectrum of the extremely variable Active Galactic Nucleus (AGN) MKN 110. By combining various archival data with new data, we cover…
A Transient "Changing-look'' Active Galactic Nucleus Resolved on Month Timescales from First-year Sloan Digital Sky Survey V Data
Grisha Zeltyn, Benny Trakhtenbrot, Michael Eracleous +32
We report the discovery of a new ``changing-look'' active galactic nucleus (CLAGN) event, in the quasar SDSS J162829.17+432948.5 at z=0.2603, identified through repeat spectroscopy…
Deciphering the extreme X-ray variability of the nuclear transient eRASSt J045650.3-203750: A likely repeating partial tidal disruption event
Zhu Liu, A. Malyali, M. Krumpe +17
(Abridged) In this paper, we present the results of an exceptional repeating X-ray nuclear transient, eRASSt J045650.3-203750 (hereafter J0456-20), uncovered by SRG/eROSITA in a qu…