Related papers: RX J1420.4+5334 - another tidal disruption event?

NGC 5905 is one of the very few galaxies that underwent a giant X-ray outburst, with a change in ROSAT photon countrate of a factor ~100. The outburst spectrum is both, very soft and luminous. Our high-resolution follow-up optical…

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 candidates discovered by the SRG/eROSITA all-sky survey. The…

One efficient method to probe the direct vicinity of SMBHs in nearby galaxies is to make use of the detection of flares from tidally disrupted stars (e.g., Lidskii & Ozernoi 1979, Rees 1988). The first few excellent candidates for the…

We present the discovery of the fading radio transient FIRST J153350.8+272729. The source had a maximum observed 5-GHz radio luminosity of $8\times10^{39}$ erg s$^{-1}$ in 1986, but by 2019 had faded by a factor of nearly 400. It is located…

IGR J19140+098 (SIMBAD corrected name IGR J19140+0951) is a new X-ray transient, discovered by INTEGRAL during an observation of GRS 1915+015. The source presents strong variations on timescales from seconds to days. We present results of…

The source XTE J1901+014 discovered by the RXTE observatory during an intense outburst of hard radiation and classified as a fast X-ray transient is studied. The source's spectral characteristics in the quiescent state have been…

Radio emission from 23 tidal disruption event host galaxies were searched in the 144 MHz LOFAR-LoTSS2 images. Three host galaxies are detected with diffuse radio emission, which can be interpreted as either galactic synchrotron radio…

We report on the detection of pulsed, broad-band, X-ray emission from the transient source RX J0117.6-7330. The pulse period of 22 seconds is detected by the ROSAT/PSPC instrument in a 1992 Sep 30 - Oct 2 observation and by the CGRO/BATSE…

We present X-ray and optical data of the newly discovered AM Her variable RX J1802.1+1804 = V884 Her. This X-ray source was observed in the ROSAT All-Sky-Survey in September 1990 and subsequently discovered as a highly variable and soft…

We report the discovery by the Swift hard X-ray monitor of the transient source Swift J2058.4+0516 (Sw J2058+05). Our multi-wavelength follow-up campaign uncovered a long-lived (duration >~ months), luminous X-ray (L_X,iso ~ 3 x 10^47 erg…

We present radio observations of the tidal disruption event candidate (TDE) XMMSL1 J0740$-$85 spanning 592 to 875 d post X-ray discovery. We detect radio emission that fades from an initial peak flux density at 1.6 GHz of $1.19\pm 0.06$ mJy…

The X-ray source 3XMM~J150052.0+015452 was discovered as a spectacular tidal disruption event candidate during a prolonged ($>11$ yrs) outburst (Lin et al. 2017). It exhibited unique quasi-soft X-ray spectra of characteristic temperature…

New high variability extragalactic sources may be identified by comparing the flux of sources seen in the XMM-Newton Slew Survey with detections and upper limits from the ROSAT All Sky Survey. In November 2012, X-ray emission was detected…

We report on SRG/eROSITA, ZTF, ASAS-SN, Las Cumbres, NEOWISE-R, and Swift XRT/UVOT observations of the unique ongoing event AT 2019avd, located in the nucleus of a previously inactive galaxy at $z=0.029$. eROSITA first observed AT 2019avd…

It has long been suggested that supermassive black holes in non-active galaxies might be tracked down by occasional tidal disruptions of stars on nearly radial orbits. A tidal disruption event would reveal itself by a luminous flare of…

We present observations of an extreme radio flare, VT J024345.70-284040.08, hereafter VT J0243, from the nucleus of a galaxy with evidence for historic Seyfert activity at redshift $z=0.074$. Between NRAO VLA Sky Survey observations in 1993…

We describe the late spectral variability and flux evolution of TDF Sw J1644+57, a Tidal Disruption Flare which left the typical potential trend proportional to $t^{-5/3}$ in 2012, maintaining a quiescent flux until nowadays. Sixteen X-ray…

The BeppoSAX Wide Field Cameras detected a transient in NGC6440 on 1998 Aug 22. ROSAT did not detect this source on 1998 Sep 8, indicating that the X-ray flux had decreased by a factor 400 at least, and/or that the X-ray spectrum had become…

We analysed 13 archival ROSAT PSPC and HRI observations which included the position of a newly discovered 59s X-ray pulsar in the Small Magellanic Cloud, 1SAX J0054.9-7226 = 2E 0053.2-7242. The source was detected three times between 1991…

In the last few years, giant-amplitude, non-recurrent X-ray flares have been observed from several non-active galaxies (NGC 5905, RXJ1242-11, RXJ1624+75, RXJ1420+53, RXJ1331-32). All of them share similar properties, namely: extreme X-ray…