Black-Hole Binary Systems

The origin of the MeV gamma ray emission from Cygnus X-1 is not well understood. Most models assume that the gamma rays are X-rays that were Comp- 

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Black holes. One great achievement of gravitational wave astronomy would be the first detection of a signal coming directly from a black hole. Just like with neutron stars, black holes can emit gw either alone or in binary systems. 

In these considerations, it must be kept in mind that there is a stellar spike around the black hole at the Galactic Center. The steepness of this stellar spike is however not very well know. With large uncertainties, Genzel et al.(2003) estimate the slope of the stellar spike to be 7stars 1.3-1.4. This means that the current stellar spike is probably shallow. We may think that the stellar spike is our best proxy for the dark matter spike. If so, also the dark matter spike would also be shallow, and thus inconsequential for neutralino signals. However, the dark matter and stellar spikes follow very different evolution histories, because contrary to the dark matter, binary collisions of stars and coalescence of two stars into one at collisions effectively relax the stellar system to a shallower spike. 

The analysis of nucleosynthesis in hypernovae suggests a possible classification scheme of supernova explosions [111]. In this scheme, core collapse in stars with initial main sequence masses Mms < 25 — 30M leads to the formation of neutron stars, while more massive stars end up with the formation of black holes. Whether or not the collapse of such massive stars is associated with powerful hypernovae ( Hypernova branch ) or faint supernovae ( Faint SN branch ) can depend on additional ( hidden ) physical parameters, such as the presupernova rotation, magnetic fields. [39], or the GRB progenitor being a massive binary system component [145, 117]. The need for other parameters determining the outcome of the core collapse also follows from the continuous distribution of C+O cores of massive stars before the collapse, as inferred from observations, and strong discontinuity between masses of compact remnants (the mass gap between neutron stars and black holes) [28]2. 

As reminded in Sect. 7.3, the decompression of the crust of cold neutron stars (NSs) made of a lattice of very neutron-rich nuclei immersed in a gas of neutrons and degenerate electrons has long been envisioned as a possible site for the development of a high-density r-process (HIDER). This decompression could result from the coalescence of two NSs or of a NS and a black hole (BH) in a binary system. It could also result from the ejection of material from magnetars. 

The binary machine is an important component in apparatuses of power. So many dichotomies will be established that there wiU be enough for everyone to be pinned to the wall, sunk in a hole. Even the divergences of deviancy will be measured according to the degree of binary choice you are neither white nor black, Arab then Or half-breed You are neither man nor woman, transvestite then This is the white wall/black hole system. And it is not surprising that the face has such importance in this system you must have the face of your role (Deleuze and Parnet 1987, 21). 

The end-over-end tumble of binary star systems is an excellent source of gravitational waves in both the LF and HF bands. The gravitational wave frequency increases with the total mass of the system, and is inversely proportional to the separation of the binary elements. Thus, compact binaries composed of neutron stars and/or stellar-mass black holes radiate at the highest frequencies since the elements can get very close together without merging. 

Black holes in binary systems spiral together, as they emit gravitational waves, just as binary neutron stars do. The gravitational waves from, and the dynamics of, the coalescence will be quite different, however. 

GRAVITATIONAL WAVES are ripples in space-time caused by the coherent accelerated motion of massive bodies. The potential gravitational wave sources span a wide range of cosmic environments neutron stars, black holes, supernovae, and binary systems. This review focuses on the instruments currently under construction that are expected to perform the first direct detection of gravitational waves. 

The simplicity of the system makes this event the potentially clearest signature for gravitational waves. The coalescence of compact binary systems—neutron star/neutron star (NS/NS), neutron star/black hole (NS/BH), black hole/black hole (BH/BH)—can provide... 

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