Related papers: RBS 1032: A Tidal Disruption Event in Another Dwar…
We report the identification of the ROSAT all-sky survey source 1RXS J154814.5-452845as new intermediate polar and present the results from follow-up optical and X-ray observations. The source shows pulsations with a period of 693 s both in…
GRB 250702B is a unique astrophysical transient characterised by its nature as a repeating gamma-ray trigger. Its properties include possible periodicity in its gamma-ray light curve, an X-ray counterpart that rose prior to the gamma-ray…
During a close encounter between a star and a supermassive black hole, the star can get disrupted by the black hole's tidal forces, resulting in a tidal disruption event (TDE). The accretion of the star's material onto the black hole…
SAX J0635.2+0533 is a binary pulsar with a very short pulsation period ($P$ = 33.8 ms) and a high long-term spin down ($\dot P$ $>$ 3.8$\times10^{-13}$ s s$^{-1}$), which suggests a rotation-powered (instead of an accretion-powered) nature…
We present simulations of the tidal disruption of a solar mass star by a $10^6M_{\odot}$ black hole. These, for the first time, cover the full time evolution of the tidal disruption event, starting well before the initial encounter and…
We report the serendipitous discovery of a bright point source flare in the Abell cluster 1795 with archival EUVE and Chandra observations. Assuming the EUVE emission is associated with the Chandra source, the X-ray 0.5-7 keV flux declined…
The tidal disruption of stars by (super-)massive black holes in galactic nuclei has been discussed in theoretical terms for about 30 years but only in the past decade have we been able to detect such events in substantial numbers. Thus, we…
CSS100217 is considered a peculiar tidal disruption event (TDE) candidate occurring in an active galactic nucleus (AGN). Unlike typical TDEs, where the post-flare luminosity is equal to that pre-flare, CSS100217 decayed to $\sim$ 0.4…
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 sources whose variability deviates from standard behavior,…
Supermassive black holes (SMBHs) are found ubiquitously in large, bulge-dominated galaxies throughout the local universe, yet little is known about their presence and properties in bulgeless and low-mass galaxies. This is a significant…
XMM-Newton and Chandra have ushered in a new era for the study of dwarf galaxies in the Local Group. We provide an overview of the opportunities, challenges, and some early results. The large number of background sources relative to galaxy…
We present follow-up photometry and spectroscopy of ZTF J0328$-$1219 strengthening its status as a white dwarf exhibiting transiting planetary debris. Using TESS and Zwicky Transient Facility photometry, along with follow-up high speed…
A repeating partial tidal disruption event (rpTDE) is typically modeled as a star on a bound orbit that is partially disrupted by a massive black hole (MBH) at each pericenter passage. For disruption to occur, the pericenter distance must…
We present multiwavelength studies of a transient X-ray source, XMMSL1 J131952.3+225958, associated with the galaxy NGC 5092 at $z=0.023$ detected in the XMM-Newton SLew survey (XMMSL). The source brightened in the 0.2--2 keV band by a…
M32 is the prototype for the relatively rare class of galaxies referred to as `compact ellipticals'. It has been suggested that M32 may be a tidally disturbed r^(1/4) elliptical galaxy, or the remnant bulge of a disk-stripped early-type…
We report on the first near-simultaneous X-ray and optical observations of RX J0806.3+1527. The source is believed to be a 321s orbital period ultra-compact binary system hosting an X-ray emitting white dwarf. Data were obtained with…
A likely tidal disruption of a star by the intermediate-mass black hole (IMBH) of a dwarf galaxy was recently identified in association with Abell 1795. Without deep spectroscopy for this very faint object, however, the possibility of a…
We present a comparison of semi-analytic models of the phase-space structure of tidal debris with observations of stars associated with the Sagittarius dwarf galaxy (Sgr). We find that many features in the data can be explained by these…
SDSS J080434.20+510349.2 is the 13th dwarf nova containing a pulsating white dwarf. Among the accreting pulsators that have experienced a dwarf novae outburst, SDSS J0804 has the most dramatic history of events within a short time scale:…
Recent observations revealed a mysterious ultra diffuse galaxy, NGC1052-DF2, in the group of a large elliptical galaxy, NGC1052. Compared to expectations from abundance matching models, the dark matter mass contained in NGC1052-DF2 is…