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The spectrum and polarization of thin accretion disks around massive black holes are calculated using an improved radiative transfer method with all of the relevant opacity sources and a full general relativistic treatment of the... more
The spectrum and polarization of thin accretion disks around massive black holes are calculated using an improved radiative transfer method with all of the relevant opacity sources and a full general relativistic treatment of the radiation propagation. It is found that the overall polarization is much smaller than previously suggested. It is predicted that the degree of polarization should show a distinct broad feature near the Lyman edge, and that the polarization plane should rotate at high frequencies. These effects would confirm the thermal nature of the observed UV radiation and the existence of massive black holes at the center of AGNs.
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... Ehud Nakar1, Avishay Gal-Yam1,2, Tsvi Piran1,3 and Derek B. Fox1 ... 27 HGF in the BATSE detection window (50 300 keV), verified by our own independent estimation derived using the observed backscatter of HGF X-rays from the moon... more
... Ehud Nakar1, Avishay Gal-Yam1,2, Tsvi Piran1,3 and Derek B. Fox1 ... 27 HGF in the BATSE detection window (50 300 keV), verified by our own independent estimation derived using the observed backscatter of HGF X-rays from the moon (Golenetskii et al. ...
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Recent measurements of the positron/electron ratio in the cosmic ray (CR) flux exhibits an apparent anomaly, whereby this ratio increases with energy between 10 and 100 GeV. In contrast, this ratio should decrease in the standard... more
Recent measurements of the positron/electron ratio in the cosmic ray (CR) flux exhibits an apparent anomaly, whereby this ratio increases with energy between 10 and 100 GeV. In contrast, this ratio should decrease in the standard scenario, in which CR positrons are secondaries ...
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... approximately past null infinity), calculate the formation of the black hole's event horizon, and follow ... We calculate the formation of an apparent horizon, followed by a weak, null, mass ... Teukolsky, WT Vetterling, and BP... more
... approximately past null infinity), calculate the formation of the black hole's event horizon, and follow ... We calculate the formation of an apparent horizon, followed by a weak, null, mass ... Teukolsky, WT Vetterling, and BP Flannery, Numerical Recipes in Fortran: The Art of Scientific ...
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A simplified analytic model of a cooling hot neutron star, motivated by detailed computer calculations, describes well the neutrinos detected from the recent supernova in the Large Magellanic Cloud. The observations do not require... more
A simplified analytic model of a cooling hot neutron star, motivated by detailed computer calculations, describes well the neutrinos detected from the recent supernova in the Large Magellanic Cloud. The observations do not require explanations that invoke exotic physics or complicated astrophysics. The parameters in this simple model are not severely constrained: 6.1(-3.6)(+3.5) x 10(52) ergs emitted in electron antineutrinos, a peak temperature of 4.2(-0.8)(+1.2) megaelectron volts, a radius of 27(-15)(+17) kilometers, and a cooling time of 4.5(-2.0)(+1.7) seconds.
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