scholarly journals Tidal disruption events from different kinds of astrophysical objects: a preliminary analysis

2016 ◽  
Vol 12 (S324) ◽  
pp. 132-133
Author(s):  
Aurora Clerici ◽  
Andreja Gomboc

AbstractTidal disruption events are a powerful tool to study quiescent massive black holes residing in the centre of galaxies. Occasionally, astrophysical objects such as stars, planets and smaller bodies are captured and tidally disrupted by the massive black hole, giving rise to a luminous flare. A detailed study of disruption parameters and the emitted radiation can give important insights on the black hole and its surroundings.

2019 ◽  
Vol 488 (3) ◽  
pp. 4042-4060 ◽  
Author(s):  
Stephen Thorp ◽  
Eli Chadwick ◽  
Alberto Sesana

ABSTRACT We compute the expected cosmic rates of tidal disruption events (TDEs) induced by individual massive black holes (MBHs) and by MBH binaries (MBHBs) – with a specific focus on the latter class – to explore the potential of TDEs to probe the cosmic population of sub-pc MBHBs. Rates are computed by combining MBH and MBHB population models derived from large cosmological simulations with estimates of the induced TDE rates for each class of objects. We construct empirical TDE spectra that fit a large number of observations in the optical, UV, and X-ray and consider their observability by current and future survey instruments. Consistent with results in the literature, and depending on the detailed assumption of the model, we find that LSST and Gaia in optical and eROSITA in X-ray will observe a total of 3000–6000, 80–180, and 600–900 TDEs per year, respectively. Depending on the survey, 1 to several per cent of these are prompted by MBHBs. In particular, both LSST and eROSITA are expected to see 150–450 MBHB-induced TDEs in their respective mission lifetimes, including 5–100 repeated flares. The latter provide an observational sample of binary candidates with relatively low contamination and have the potential of unveiling the sub-pc population of MBHBs in the mass range $10^5\lt M\lt 10^7\, \mathrm{M}_\odot$, thus informing future low-frequency gravitational wave observatories.


Science ◽  
2019 ◽  
Vol 363 (6426) ◽  
pp. 531-534 ◽  
Author(s):  
Dheeraj R. Pasham ◽  
Ronald A. Remillard ◽  
P. Chris Fragile ◽  
Alessia Franchini ◽  
Nicholas C. Stone ◽  
...  

The tidal forces close to massive black holes can rip apart stars that come too close to them. As the resulting stellar debris spirals toward the black hole, the debris heats up and emits x-rays. We report observations of a stable 131-second x-ray quasi-periodic oscillation from the tidal disruption event ASASSN-14li. Assuming the black hole mass indicated by host galaxy scaling relations, these observations imply that the periodicity originates from close to the event horizon and that the black hole is rapidly spinning. Our findings demonstrate that tidal disruption events can generate quasi-periodic oscillations that encode information about the physical properties of their black holes.


2019 ◽  
Vol 485 (3) ◽  
pp. 4413-4422 ◽  
Author(s):  
Daniel J D’Orazio ◽  
Abraham Loeb ◽  
James Guillochon

ABSTRACT The rate of tidal disruption flares (TDFs) per mass of the disrupting black hole encodes information on the present-day mass function (PDMF) of stars in the clusters surrounding super massive black holes. We explore how the shape of the TDF rate with black hole mass can constrain the PDMF, with only weak dependence on black hole spin. We show that existing data can marginally constrain the minimum and maximum masses of stars in the cluster, and the high-mass end of the PDMF slope, as well as the overall TDF rate. With $\mathcal {O}(100)$ TDFs expected to be identified with the Zwicky Transient Facility, the overall rate can be highly constrained, but still with only marginal constraints on the PDMF. However, if ${\lesssim } 10 {{\ \rm per\ cent}}$ of the TDFs expected to be found by LSST over a decade ($\mathcal {O}(10^3)$ TDFs) are identified, then precise and accurate estimates can be made for the minimum stellar mass (within a factor of 2) and the average slope of the high-mass PDMF (to within $\mathcal {O}(10{{\ \rm per\ cent}})$) in nuclear star clusters. This technique could be adapted in the future to probe, in addition to the PDMF, the local black hole mass function and possibly the massive black hole binary population.


2019 ◽  
Vol 489 (1) ◽  
pp. 727-737 ◽  
Author(s):  
Giacomo Fragione ◽  
Nathan W C Leigh ◽  
Rosalba Perna ◽  
Bence Kocsis

ABSTRACT Stars passing too close to a black hole can produce tidal disruption events (TDEs), when the tidal force across the star exceeds the gravitational force that binds it. TDEs have usually been discussed in relation to massive black holes that reside in the centres of galaxies or lurk in star clusters. We investigate the possibility that triple stars hosting a stellar black hole (SBH) may be sources of TDEs. We start from a triple system made up of three main-sequence stars and model the supernova (SN) kick event that led to the production of an inner binary comprised of an SBH. We evolve these triples with a high-precision N-body code and study their TDEs as a result of Kozai–Lidov oscillations. We explore a variety of distributions of natal kicks imparted during the SN event, various maximum initial separations for the triples, and different distributions of eccentricities. We show that the main parameter that governs the properties of the SBH–MS binaries that produce a TDE in triples is the mean velocity of the natal kick distribution. Smaller σ’s lead to larger inner and outer semimajor axes of the systems that undergo a TDE, smaller SBH masses, and longer time-scales. We find that the fraction of systems that produce a TDE is roughly independent of the initial conditions, while estimate a TDE rate of $2.1\times 10^{-4}{\!-\!}4.7 \, \mathrm{yr}^{-1}$, depending on the prescriptions for the SBH natal kicks. This rate is almost comparable to the expected TDE rate for massive black holes.


1998 ◽  
Vol 184 ◽  
pp. 397-398
Author(s):  
Eric Emsellem

Massive black holes are now thought to be present at the centre of a fair fraction of nearby galaxies. The origin of these central dark masses is still unknown, although tentative explanations have been proposed in an attempt to reconcile non-active galaxies with AGNs and quasars. The activity of a galaxy may then mostly depend on the efficiency of gas accretion onto the central dark object. It is important to note that many of the galaxies which are today candidates for the presence of a massive black hole are spirals. In this context, bars should play an important role in the evolution (and formation?) of a central mass, since (1) they are present in a significant fraction of spirals, (2) they may be efficient drivers of gas accretion. If indeed most of present day galaxies hosts a central dark mass, then bars and black holes should coexist in a significant fraction of them. We examine here the cases of 3 edge-on galaxies which are candidates for the presence of a central black holes: NGC 4570, NGC 3115 and M 104.


2008 ◽  
Vol 4 (S252) ◽  
pp. 343-344
Author(s):  
Y. Lu ◽  
Y. F. Huang ◽  
S. N. Zhang ◽  
P. Lu

AbstractWe investigate the tidal disruption of a red giant whose envelope is thought to be stripped off when it passed by a massive black hole. Since the low-density stellar envelope would be lost, the tidal disruption of a red giant by massive black hole is regarded as primarily happening in its core region. The object is called a stripped red giant (SRG). Comparing our results with the three candidate tidal disruption events detected by Chandra in 2001 and 2002, i.e., the X-ray flares of NGC 5905, RX J1242.6-1119A, and RX J1624.9+7554, we argue that the tidal disruption of a stripped red giant is strongly ruled out.


Author(s):  
Michael L Katz ◽  
Luke Zoltan Kelley ◽  
Fani Dosopoulou ◽  
Samantha Berry ◽  
Laura Blecha ◽  
...  

Abstract ESA and NASA are moving forward with plans to launch LISA around 2034. With data from the Illustris cosmological simulation, we provide analysis of LISA detection rates accompanied by characterization of the merging massive black hole population. Massive black holes of total mass ∼105 − 1010M⊙ are the focus of this study. We evolve Illustris massive black hole mergers, which form at separations on the order of the simulation resolution (∼kpc scales), through coalescence with two different treatments for the binary massive black hole evolutionary process. The coalescence times of the population, as well as physical properties of the black holes, form a statistical basis for each evolutionary treatment. From these bases, we Monte Carlo synthesize many realizations of the merging massive black hole population to build mock LISA detection catalogs. We analyze how our massive black hole binary evolutionary models affect detection rates and the associated parameter distributions measured by LISA. With our models, we find massive black hole binary detection rates with LISA of ∼0.5 − 1 yr−1 for massive black holes with masses greater than 105M⊙. This should be treated as a lower limit primarily because our massive black hole sample does not include masses below 105M⊙, which may significantly add to the observed rate. We suggest reasons why we predict lower detection rates compared to much of the literature.


2009 ◽  
Vol 5 (S267) ◽  
pp. 26-33 ◽  
Author(s):  
Marta Volonteri

AbstractMassive black holes (MBHs) are nowadays believed to reside in most local galaxies. Studies have also established a number of relations between the MBH mass and properties of the host galaxy such as bulge mass and velocity dispersion. These results suggest that central MBHs, while much less massive than their hosts (~ 0.1%), are linked to the evolution of galactic structure. When did it all start? In hierarchical cosmologies, a single big galaxy today can be traced back to the stage when it was split up in hundreds of smaller components. Did MBH seeds form with the same efficiency in small proto-galaxies, or did their formation have to await the buildup of substantial galaxies with deeper potential wells? I briefly review here some of the physical processes that are conducive to the evolution of the massive black hole population. I will discuss black hole formation processes for “seed” black holes that are likely to take place at early cosmic epochs, and possible observational tests of these scenarios.


2005 ◽  
Vol 13 ◽  
pp. 350-353
Author(s):  
Holger Baumgardt ◽  
Junichiro Makino ◽  
Simon Portegies Zwart

AbstractWe present results of N-body simulations on the formation of massive black holes by run-away merging in young star clusters and the later dynamical evolution of star clusters containing massive black holes. We determine the initial conditions necessary for run-away merging to form a massive black hole and study the equilibrium profile that is established in the cluster center as a result of the interaction of stars with the central black hole. Our results show that star clusters which contain black holes have projected luminosity profiles that can be fitted by standard King models. The presence of massive black holes in (post-)core collapse clusters is therefore ruled out by our simulations.


2019 ◽  
Vol 28 (14) ◽  
pp. 1944015
Author(s):  
Martina Toscani ◽  
Giuseppe Lodato ◽  
Elena Maria Rossi

Stars are spheres of gas held together by self-gravity. When flying by a black hole, however, the star self-binding force can be overwhelmed by the black hole tides and the star can be torn apart. This is a physically rich and fascinating event which will be described by first introducing the concept of black hole from a mathematical point of view. We will then dive into the physics of the tidal disruption and proceed describing the accompanying electromagnetic flare and gravitational wave burst in the frequency range of the Laser Interferometer Space Antenna. This empowers such events to discover the elusive black holes with mass intermediate between the solar and the million/billion solar masses.


Sign in / Sign up

Export Citation Format

Share Document