Galactic center

STUDIES OF THE GALACTIC CENTER. III. THE ABSOLUTE MAGNITUDES OF LONG PERIOD VARIABLES... 

INSs may lurk within unidentified EGRET and ROSAT sources and, possibly, among dim X-ray sources observed by XMM-Newton and Chandra in globular cluster (see Pfahl, Rappaport 2001) or in the galactic center (see Muno et al. 2003). Except PSRs all others are more or less radioquiet (which, however, does not mean that they are necessarily radio silent). 

Due to the presence of the Belt the rate of SN around us (say in few hundred parsecs) during the last several tens of million years is higher, than it is in an average place at a solar distance from the galactic center. Because of that there should be a local overabundance of young NSs which can appear as hot cooling objects, as gamma-ray sources etc. 

Muno, M.P. et al. (2003), A deep Chandra catalog of X-ray point sources toward the galactic center , ApJ 589, 225. 

Solar system Outer galaxy Galactic center... 

Anticipated next supernova in our Galaxy may be undetectable by the optical instrument due to the Galactic extinction. However, supernovae are now known to be intense radio sources after a year or so of the explosion. Even if the positions are beyond the Galactic center, the radio supernova could be observed using middle size radio telescope. 

That the redshifts of galaxies measured with respect to our own galactic center were quantized in steps of 36 km/s... 

Figure 1. The power spectrum analysis of Guthrie and Napier s first sample of 97 redshifts. This peak power occurs when redshifts are corrected for the solar motion with respect to our galactic center.

Figure 16.24. Sensitivity of upcoming gamma-ray telescopes to neutralino models that can explain the HEAT positron excess with neutralino clumps in the galactic halo. Model points are indicated by crosses circles denote those models that in addition can also account for the measured deviation in the muon magnetic moment. The upper set of sensitivity curves corresponds to the high latitude gamma-ray line flux (scale on the left) the lower set of curves to the direction toward the galactic center (scale on the right no steep spike around the central black hole is assumed). (Figure from Baltz, Edsjo, Freese, Gondolo(2002).)...

Signals from neutralino annihilation at the Galactic Center. The last indirect neutralino signals we consider are neutrinos, gamma-rays and radio... 

Further evidence for a black hole at the center of the Milky Way comes from the 2001 observation of a X-ray and infrared flares from the Galactic Center Baganoff et al.(2001) Porquet et al.(2003) Genzel et al.(2003b). The flare time scale and intensity can nicely be explained if the flare is produced near a black hole , see, e.g.,]Aschenbach 2004. 

Neutralino annihilation is enhanced in the spike, because of the dependence of the annihilation rate on square of the density. The Galactic Center then becomes a source of neutrinos, gamma-rays, radio waves, etc. from neutralino annihilation (Figure 26). The intensity of the emission depends on the steepness of the spike. If the spike is shallow, neutralino annihilation is generally undetectable. On the contrary, a steep spike at the Galactic Center produces interesting signals. 

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